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 The views expressed in this report

 are those of the authors. 

 No endorsement by MedPAC

 is intended or should be inferred.

A study conducted by

RAND Health for the

Medicare Payment Advisory Commission

November 2004 • No.0 4 
Services Provided in 

Multiple Ambulatory 

Settings 

A Review of the Literature for 

Selected Procedures 

LISA R. SHUGARMAN, CONSTANCE FUNG, 

HARLINAH LOPEZ, AND BARBARA O. WYNN 

WR-151-MedPAC 

July 2004 

WORKING 

P A P E R

This product is part of the RAND 

Health working paper series. 

RAND working papers are intended 

to share researchers’ latest findings 

and to solicit informal peer review. 

They have been approved for 

circulation by RAND Health but 

have not been formally edited 

or peer reviewed. Unless otherwise 

indicated, working papers can be 

quoted and cited without permission 

of the author, provided the source is 

clearly referred to as a working paper. 

RAND’s publications do not necessarily 

reflect the opinions of its research 

clients and sponsors. 

 is a registered trademark. 

iii

TABLE OF CONTENTS 

TABLE OF CONTENTS...............................................................................................................iii 

LIST OF FIGURES ........................................................................................................................ v 

EXECUTIVE SUMMARY .......................................................................................................... vii 

Section 1. INTRODUCTION ........................................................................................................ 1 

Study Questions................................................................................................................... 2 

Section 2. LITERATURE REVIEW ............................................................................................. 5 

Methods............................................................................................................................... 5 

Literature Selection and Retrieval...................................................................................... 6 

Article Abstraction.............................................................................................................. 6 

Section 3. CATARACT SURGERY ............................................................................................. 7 

Literature Search Results.................................................................................................... 7 

Setting of Care and Provider of Service ............................................................................. 8 

Sample Description............................................................................................................. 9 

Process Measures............................................................................................................... 9 

Complications Related to Cataract Surgery....................................................................... 9 

Complications Unrelated to the Eye: Anesthesia Complications.................................... 11 

Complications Unrelated to the Eye: Medical Complications, Hospitalizations, and 

Death................................................................................................................................. 12 

Data Sources for Tracking Complications ....................................................................... 13 

Section 4. CRANIAL AND SPINAL MAGNETIC RESONANCE (MR) IMAGING .............. 15 

Literature Search Results.................................................................................................. 15 

Setting of Care .................................................................................................................. 16 

Sample Description........................................................................................................... 16 

Structure Measures........................................................................................................... 17 

Complications/Adverse Events Related to Cranial/Spinal MR Imaging .......................... 17 

Safety Concerns Not Covered in Abstracted Literature ................................................... 19 

Data Sources for Tracking Complications ....................................................................... 20 

Section 5. COLONOSCOPY....................................................................................................... 21 

Literature Search Results.................................................................................................. 21 

Setting of Care and Provider of Service ........................................................................... 22 

Sample Description........................................................................................................... 23 

Process Measures............................................................................................................. 23 

Complications Related to Colonoscopy............................................................................ 24 

Complications Unrelated to the Colon ............................................................................. 26 

Data Sources for Tracking Complications ....................................................................... 27 

Section 6. REFERENCES ........................................................................................................... 29 

Appendix A.1 Cataract Surgery Evidence Tables ........................................................................ 35 

Appendix A.2 Cranial and Spinal Magnetic Resonance (MR) Imaging Evidence Tables........... 49 
iv

Appendix A.3 Colonoscopy Evidence Tables .............................................................................. 69 

Appendix B.1 Annotated Bibliography for Selected Cataract Articles ...................................... 103 

Appendix B.2 Annotated Bibliography for Selected Cranial and Spinal (MR) Imaging Articles

..................................................................................................................................................... 111 

Appendix B.3 Annotated Bibliography for Selected Colonoscopy Articles .............................. 117 

Appendix C.1 Screening Form for MedPAC Literature Review Cataracts................................ 131 

Appendix C.2 Screening Form for MedPAC Literature Review Cranial and Spinal Magnetic 

Resonance (MR) Imaging........................................................................................................... 137 

Appendix C.3 Screening Form for MedPAC Literature Review Colonoscopy.......................... 143 
v

LIST OF FIGURES 

Figure 3.1 Search Results for the Cataract Surgery Review.......................................................... 8 

Figure 4.1 Search Results for the Cranial and Spinal MR Imaging Review ............................... 16 

Figure 5.1 Search Results for the Colonoscopy Review.............................................................. 22 
vi
vii

EXECUTIVE SUMMARY 

 While ambulatory procedures can be performed in a variety of settings, most are 

performed in three settings: hospital outpatient departments, ambulatory surgery centers, and 

physician offices. Technological advances such as improved anesthesia and pain management 

coupled with health care financing changes have produced a shift in services from inpatient to 

outpatient services and increased the volume and complexity of procedures provided in 

ambulatory settings. Very little is known about the quality of care implications of the shift from 

inpatient to ambulatory care and how patient and procedure characteristics vary among 

ambulatory settings. 

 The Medicare Payment Advisory Commission (MedPAC) asked RAND to identify highvolume services provided in multiple ambulatory settings, such as physicians’ offices, hospital 

outpatient departments (OPDs), and ambulatory surgical centers (ASCs) and examine the 

feasibility of using administrative data to analyze how the nature of a service, the patient 

characteristics, and outcomes vary by the setting in which the service is provided. These 

analyses are prerequisites for evaluating quality and policy issues such as the appropriateness of 

site-of-service payment differentials across ambulatory settings for the same procedure. 

 In this report, we describe the results of a review of the clinical literature for three 

selected procedures: cataract surgery, spinal and cranial magnetic resonance (MR) imaging, and 

colonoscopy. We reviewed selected studies on these procedures, abstracting data on the 

procedures covered, study design, study setting (limiting these to ambulatory settings), 

provider(s) performing procedure, population characteristics, reason for procedure, sample size, 

inclusion/exclusion criteria, process and outcome measures, method of process and outcome 

measure assessment, and findings from the study. We also tried to compare patient 

characteristics and outcomes across settings of care and comment on the potential for tracking 

selected measures in administrative data. The results of this review will support subsequent 

project activities including expert panel review of quality measures and risk associated with 

selected patient characteristics as well as an analysis of administrative data to test the feasibility 

of tracking these measures in Medicare claims. A review of the efficacy of the procedures was 

beyond the scope of our study. 

 The literature reported fairly consistently the set of process measures and major and 

minor complications of each procedure. Overall, the literature that we reviewed on each of the 

three procedures was silent on the issue of differences in patient characteristics, process 

measures, and outcomes of care across settings of care. Only a small subset of studies examined 

the patient characteristics associated with complications of care. We were able to identify 

indirectly potential measures for understanding differences across sites of care. For example, the 

colonoscopy procedure may be performed as a diagnostic tool, for biopsy purposes, or as a 

therapeutic tool (i.e., polypectomy). We might be able to explore differences in the relative 

distribution and outcomes for these three types of colonoscopy procedure across sites of care and 

explore whether patient characteristics differ as well. 
viii
1

SECTION 1. INTRODUCTION 

 Increasing Volume and Complexity of Ambulatory Procedures. While ambulatory 

procedures can be performed in a variety of settings, most are performed in three settings: 

hospital outpatient departments, ambulatory surgery centers, and physician offices. Other 

settings include freestanding independent diagnostic testing facilities (IDTFs), community health 

centers, and rural health clinics. Technological advances such as improved anesthesia and pain 

management coupled with health care financing changes have produced a shift in services from 

inpatient to outpatient services and increased the volume and complexity of procedures provided 

in ambulatory settings. Very little is known about the quality of care implications of the shift 

from inpatient to ambulatory care and how patient and procedure characteristics vary among 

ambulatory settings. 

 Medicare Payment Incentives. Medicare’s coverage of surgical procedures in 

ambulatory surgical centers (ASCs) beginning in 1982, implementation of the Medicare 

prospective payment system (PPS) for acute care inpatient hospital services in 1983, and the 

growth of Medicare managed care have created financial incentives to shift services to 

ambulatory settings. More recently, the different payment amounts for the facility component of 

ambulatory procedures (that is, the prospective payments for hospital outpatient services, the 

ASC facility rate, and the practice expense component of the physician fee schedule) have raised 

concerns that financial incentives could influence the choice of ambulatory setting and affect 

beneficiary access and quality of care as well as Medicare expenditures.1,2 The differentials are 

caused by the payment systems for each setting: 

• A prospective payment system for hospital outpatient services was implemented in 

August 2000 that uses an Ambulatory Payment Classification (APC) system to group 

clinically coherent sets of procedures that require similar resources. A prospective 

payment rate for each APC is based on median cost for the procedures in the group 

relative to the procedures in other APCs. 

• Approved ambulatory surgery procedures are combined into 9 payment groups and paid 

based on facility overhead expenses and procedure-specific charges from a 1986 ASC 

survey with periodic adjustments for intervening inflation. 

• Beginning in 1999, the practice expense component of the physician fee schedule was 

transitioned from relative values related to historical charges for each service to resourcebased relative values. The practice expense relative value units for a particular procedure 

differ based on whether it is furnished in a facility (e.g., hospital outpatient department or 

ASC) or a physician’s office. 

 ASCs are required to meet health and safety standards established by the Centers for 

Medicare and Medicaid Services (CMS) as well as any applicable state licensure requirements. 

Restrictions have been placed on the procedures that are eligible for an ASC facility fee to ensure 

patient safety as well as to encourage the movement of procedures from inpatient settings and 

preclude a shift from physician offices. ASCs receive facility payments for only those 

 

1

 The sustainable growth rate used to determine the physician fee schedule update has also been cited as potentially 

affecting where care is delivered since physician services are included in the calculation but ASC and hospital 

outpatient services are not. 

2

 Services furnished in an independent diagnostic treatment facility are paid under the same policies as services 

furnished in an office setting. 
2

procedures that are on the approved list of ASC procedures. Before 2001, no limitations were 

placed on procedures that could be performed in a hospital outpatient department (including 

those located some distance from the hospital’s main campus). However, as part of the 

outpatient PPS rulemaking process, certain procedures have been identified as being safely 

performed in an inpatient setting only and are not eligible for a facility fee when they are 

performed in a hospital outpatient department. No coverage limitations have been placed on 

where physician services may be performed, but there are no non-facility practice expense 

relative values for services that are essentially performed only in facility settings. 

Study Questions 

The Medicare Payment Advisory Commission (MedPAC) asked RAND to identify highvolume services provided in multiple ambulatory settings, such as physicians’ offices, hospital 

outpatient departments (OPDs), and ambulatory surgical centers (ASCs) and examine the 

feasibility of using administrative data to analyze how the nature of a service, the patient 

population, and outcomes vary by the setting in which the service is provided. These analyses 

are prerequisites for evaluating quality and policy issues such as the appropriateness of site-ofservice payment differentials across ambulatory settings for the same procedure.3

 They address a 

limited set of preliminary questions: 

1. Which procedures are provided in more than one ambulatory setting? Which of 

these are high volume? 

2. Does the medical literature identify the conditions under which certain procedures 

should be provided in a particular setting or that outcomes for particular types of 

patients are sensitive to where a certain procedure is performed? 

3. What outcomes and indicators that can be monitored with administrative data 

might be used to assess differences in patient characteristics and the processes and 

quality of care across ambulatory settings for certain procedures? 

Our study involves three sequential tasks: 

1. In the initial task, RAND, in conjunction with MedPAC and Social and Scientific 

Systems, Inc., used 2000 Medicare Part B claims data for a 5% beneficiary 

sample to identify high volume procedure groupings provided in at least two of 

four ambulatory settings: ambulatory surgical centers, hospital outpatient 

departments, physicians’ offices, and independent diagnostic testing facilities. 

The high volume procedures that were considered candidates for further study 

met two basic criteria: 

a) the procedure was performed in at least two sites of care (>10% of total 

volume in each site). 

b) the procedure was among the top 25 in terms of total volume or expenditures. 

 

3

 While the issue of whether there are financial incentives that might affect whether care is provided inappropriately 

in an inpatient vs. outpatient setting remains an important issue, the study focus is on the variations in procedures 

performed in ambulatory settings. Medicare site of service payment differentials for ambulatory procedures may 

adversely affect beneficiary access to appropriate care or the efficient delivery of needed health care services. 
3

MedPAC, in consultation with the RAND Corporation, reviewed the high volume procedures 

and selected three procedures for further study: colonoscopy, cataract surgery, and spinal and 

cranial magnetic resonance imaging (MRI). The objective was to choose a diverse set of study 

procedures that vary by type (e.g., surgical vs. non-surgical), potential safety concerns, and 

where they are performed. 

2. The second task, which is the subject of this report, is an in-depth literature 

review for the three high-volume procedures selected for further study. The 

literature review focuses on research related to outcome and process indicators for 

the study procedures, including any studies on the relationship between the setting 

and patient characteristics, processes of care, and outcomes. A review of the 

efficacy of the procedures was beyond the scope of the study. 

3. Using the results of the literature review, the third task will explore the feasibility 

of using administrative data to measure the quality and process indicators and to 

evaluate the extent to which the patient population and/or the nature of the service 

within the study procedure groupings vary by setting. The task involves both an 

expert panel to rate which measures would be most appropriate for investigating 

variations in these procedures across ambulatory settings and analysis of 

Medicare claims data. 
4
5

SECTION 2. LITERATURE REVIEW 

 In this report, we describe the results of a review of the clinical literature for the three 

selected procedures. In this task, we focus on describing potential quality indicators based on 

reports in the literature. To the extent possible, we describe how process and outcome measures 

vary across sites of care and how populations vary across sites of care. Finally, we review the 

sources of data used to produce the quality indicators and whether or not they can be easily 

monitored using administrative data or whether chart review or provider/patient questionnaires 

will be most appropriate for monitoring differences in quality of these procedures across site of 

care. In the following section, we describe the methods by which we selected the literature for 

more detailed review. In the chapters to follow, findings from the literature are described for 

each procedure separately. 

Methods 

Literature Search. We compiled a list of search terms for the literature searches on the 

selected procedure groupings in Medline/PubMed. We explored the utility of LocatorPlus, 

Embase, CINAHL, and the Cochrane collection of databases as well with the colonoscopy 

procedure and did not find any additional references to supplement those identified in 

Medline/PubMed and thus, we did not pursue searches of relevant literature for cataracts or MRI 

of the brain in these databases. All relevant English-language articles for the review were 

identified from the database. 

In selecting the appropriate time frame in which to search for articles, we consulted 

clinicians with expertise in the procedures that are the focus of this study. With respect to 

colonoscopy, most major changes in colonoscope technology and colonoscopy procedure that 

might affect the outcomes we planned to study appear to have taken place prior to 1990. 

Therefore, we limited our literature search for the colonoscopy procedure to articles published 

between 1990 and 2003. We found that this same timeframe (1990 to 2003) was appropriate for 

the cataract procedure as well. As many of the complications for MRI arise from the contrast 

dye used during the procedure, we wanted to include studies that report on the most commonly 

used contrast dyes. Magnevist, a contrast dye used with MRI, was introduced into most markets 

in 1988. In consideration of this and after consultation with radiologists, we selected studies 

related to spinal and cranial MRI published between 1988 and 2003. 

The following search terms were generally applied to the literature searches of all three 

procedures: adverse effects, adverse events, complications, outcomes, outcome assessment, 

quality, quality assurance, quality improvement, quality indicator, quality of care, ambulatory 

surgical center, ambulatory care, ambulatory surgical procedures, emergency department, 

emergency room, hospital outpatient department, outpatient procedures, outpatient surgery, 

physician office and outpatient clinics. 

Procedure-specific search terms were as follows: for colonoscopy, we used colonoscopy; 

for cataracts, we used cataract, cataract surgery, phacoemulsification, small-incision cataract 

surgery, and intraocular lens; for spinal and cranial MRI, we used magnetic resonance 

imaging, image enhancement, contrast media, drug hypersensitivity, drug tolerance, 

Gadolinium DTPA, Meglumine, organometallic compounds, pentetic acid, and heterocyclic 

compounds. 
6

Literature Selection and Retrieval 

 The literature search produced a set of titles and abstracts for each procedure to be 

reviewed. Each list was reviewed by two researchers to identify research articles reporting on 

quality of care or complications specific to the conduct of the selected procedures. We excluded 

abstracts that did not focus on quality or complications specific to the procedure and those for 

which the study setting was clearly an inpatient setting. Additionally, studies of pediatric 

populations and Phase I drug trials were excluded. A list reflecting the union of the researchers’ 

reviews of the titles and abstracts was developed and articles for subsequent review and 

abstraction were retrieved. 

Article Abstraction 

 Articles were identified as described above for abstraction based on a title and abstract 

review. For each procedure, we developed an abstraction tool to gather data on the procedure(s) 

covered, study design, study setting, provider(s) performing procedure, population 

characteristics, reason for procedure, sample size, inclusion/exclusion criteria, process and 

outcome measures, method of process and outcome measure assessment, and findings from the 

study. Process measures include length of procedure, sedation procedures, and preparation for 

procedure. Outcome measures in this review focused exclusively on complications of each 

procedure and associated sedation procedures as measures of quality. The literature did not 

address differences in positive outcomes of treatment across settings. Abstraction of information 

on the efficacy of each procedure (i.e., visual acuity for cataract) was beyond the scope of the 

project. Copies of the abstraction forms are included in Appendix C. At this stage, we excluded 

any articles employing a non-U.S. based sample, that did not report on the process of care, 

complications or other outcomes, and further excluded studies that, upon closer inspection, took 

place in an inpatient setting. For the review of colonoscopy and cataract procedures, we also 

excluded studies where the setting of care was not specified or unclear. We did not apply this 

same rule for MR imaging as almost all studies otherwise eligible for inclusion did not specify 

the setting of the procedure. Finally, we excluded review articles and meta-analyses however, 

information from these papers were included in the text where useful to illustrate a point. 
7

SECTION 3. CATARACT SURGERY 

 In this section, we summarize the findings from the literature regarding process and 

outcome/complication measures of cataract removal procedures. Extracapsular cataract 

extraction (ECCE) and Phacoemulsification with or without intraocular lens implantation are 

among the most common surgical procedures performed in the United States (National Eye 

Institute 2003). As a result of administrative changes made by the Health Care Financing 

Administration (now the Centers for Medicare and Medicaid Services – CMS), the conduct of 

cataract extraction has shifted almost entirely to outpatient settings (Holland, Earl et al. 1992). 

As of 1994, almost 100% of all cataract surgeries are performed in a hospital outpatient 

department, ambulatory surgical center or physician’s office (Javitt, Street et al. 1994). Based on 

analyses performed in an earlier task of this project, among those cataract removal procedures 

performed on an outpatient basis, 47.7 % were performed in a hospital outpatient department, 

51.8% were performed in an ambulatory surgical center, and only 0.5% were performed in a 

physician’s office. 

Most cataract removal surgeries are uncomplicated and lead to improved visual acuity 

and patient satisfaction. In some cases however, postoperative complications arise including 

retinal detachment, intraocular lens malposition or dislocation, vitreous loss, endophthalmitis, 

aphakic and pseudophakic bullous keratopathy, iris prolapse, cystoid macular edema, corneal 

edema, intraocular pressure, chronic uveitis, or vision loss. Other complications may arise from 

the sedation or anesthesia used during the procedure. Complications unrelated to the eye 

associated with general anesthesia include death, myocardial infarction, arrhythmia, hypotension, 

hypertension, aspiration, nausea, vomiting, and confusion. Complications arising from local 

(injected) anesthesia include retrobulbar hemorrhage, globe perforation, strabismus, respiratory 

arrest, ptosis, and confusion. 

Tables summarizing clinical studies selected for abstraction can be found in Appendix 

A.1. The text that follows summarizes our understanding of outcomes of the procedure in terms 

of variation across sites of care (ambulatory surgical center, physician’s office, and hospital 

outpatient department), any variation in the patient populations cared for in each setting, and a 

description of the quality measures and what, if any, differences can be detected in process 

measures or complications across site of care. Finally, we address the availability of data to 

compare process measures and complications across sites of care. 

Literature Search Results 

 Figure 3.1 describes the results of our literature search for clinical studies on cataract 

surgery. A total of 343 abstracts and/or titles were identified through our search procedures 

described in Section 2. In the first stage of review, abstracts or titles were rejected if the study 

setting was clearly an inpatient setting or the study focus was not related to process or 

complications of the procedure. We identified 42 titles/abstracts for further review and 

abstraction. Of this subset of articles, 28 (66.7%) were further excluded for the following 

reasons: study setting was not an outpatient setting or setting was unclear (9, 21.4%), the study 

was based on a non-U.S. population (12, 28.6%), or no process measures or complications were 

reported relating to the procedure (7, 16.7%). Of the 14 articles selected for abstraction, five 

reported on the process of the procedure or complications related to anesthesia and eleven 

reported on outcomes or complications directly related to the procedure. The primary limitation 
8

of this literature review relates to study design. Only two of the fourteen studies selected for 

review were randomized controlled trials and randomization was related to type of anesthesia 

rather than setting of care. 

Figure 3.1 Search Results for the Cataract Surgery Review 

Titles/Abstracts Retrieved from 

Literature Search

N = 343

Papers Retrieved from 

Title/Abstract Review

N = 42 (12.3%)

Papers Accepted for 

Abstraction 

N=14 (4.1%)

Titles/Abstracts 

Excluded

N = 301

Articles Excluded 

(N=28, 66.7%)

• Foreign Article (12, 

28.6%)

• Other Setting of Care 

(9, 21.4%)

• No Process Measures 

or Complications 

Reported (7, 16.7%)

Setting of Care and Provider of Service 

 Of the 14 studies considered, ten were based in ambulatory surgical centers (Mayer and 

O'Connor 1993; Shammas 1996; Ascaso, Ayala et al. 1997; Kollarits, Jaweed et al. 1998; 

Bohigian 1999; Rosenfeld, Litinsky et al. 1999; Golnik, West et al. 2000; Harman 2000; Ahmed, 

Zabriskie et al. 2002). One study incorporated data on cataract surgery from ambulatory surgical 

centers and inpatient facilities (Katz, Feldman et al. 2001). One study compared the 

complications of cataract surgery between an inpatient and a hospital outpatient department 

(Holland, Earl et al. 1992). Two other studies examined complications of cataract surgery across 

all care settings (inpatient, hospital outpatient department, ambulatory surgical center, and 

physician’s office) using the same Medicare administrative claims database (Javitt, Tielsch et al. 

1992; Javitt, Street et al. 1994). One of these studies reported complications for the overall 

sample and for an earlier inpatient-only sample (Javitt, Street et al. 1994) while the other made 

no distinction in complication rates across settings (Javitt, Tielsch et al. 1992). Considering the 

lack of variation in settings of care in the selected literature, our subsequent ability to compare or 

contrast process measures or complication rates across sites of care from the literature will be 

limited. 

 All but two of the selected studies identified an ophthalmologist as the provider 

performing the cataract removal. The two studies that did not report the specialty of the provider 

of service used Medicare administrative claims for their study and did not specify whether they 

selected claims for cataract surgeries performed by ophthalmologists (Javitt, Tielsch et al. 1992; 

Javitt, Street et al. 1994). Three studies specified an academic setting for all or most of the 

procedures included in their report (Holland, Earl et al. 1992; Katz, Feldman et al. 2001; Ahmed, 

Zabriskie et al. 2002). One study took place in a Veteran’s Administration facility (Corey and 

Olson 1998). 
9

Sample Description 

 The selected studies did not consistently provide descriptive information about the patient 

samples included in their reports. Additionally, some studies had fairly strict inclusion or 

exclusion criteria that make comparing samples difficult. In general, study samples were older 

and female. Three studies specifically selected a sample comprised mostly or entirely of 

Medicare-eligible population age 65 and older (Javitt, Tielsch et al. 1992; Javitt, Street et al. 

1994; Katz, Feldman et al. 2001). Although most papers described their study samples, only two 

studies (Javitt, Tielsch et al. 1992; Javitt, Street et al. 1994) examined the association of patient 

characteristics with complications of care (in both cases, they examined retinal detachment; see 

below). 

Process Measures 

Only one study reported process measures, specifically procedure time in which the 

variation in length of the procedure was described by the type of anesthesia and sedation 

administration. Katz and colleagues (2001) found substantial variation in surgery time for 

cataract surgeries performed on an inpatient basis or in an ambulatory surgical center setting, 

ranging from a mean of 16 minutes for patients who received injection anesthesia combined with 

IV sedatives to a mean of 43.8 minutes for those who received injection anesthesia combined 

with opioids and either oral or IV sedatives. The data on mean surgery time was not 

differentiated by site of care (inpatient vs. ASC). 

Complications Related to Cataract Surgery 

 All fourteen articles reported complications associated with cataract surgery. Ten 

identified complications directly related to the cataract surgery and the eye. Five articles 

identified complications of cataract surgery unrelated to the eye (described in the next section). 

In this section, we summarize the major and minor complications reported in the literature 

related to cataract surgery. No studies compared complication rates across the three settings of 

interest. One study by Holland and colleagues (1992) compared complication rates across 

inpatient and hospital outpatient department settings and a study by Javitt and colleagues (1994) 

compared rates of complications found in administrative claims for an inpatient sample and a 

sample that included patients who had cataract surgery in any setting (inpatient, outpatient, ASC, 

and physician’s office). No study described surgeries taking place specifically in a physician’s 

office. 

Retinal Detachment/Break: One of the most serious complications of cataract surgery 

is retinal detachment. The most common type of retinal detachment is rhegmatogenous retinal 

detachment. In this situation, a tear or break in the retina causes it to separate from the retinal 

pigment epithelium (RPE) and fill with fluid (National Eye Institute 2003). In some cases, the 

retina may tear without detaching from the RPE. These tears are often called retinal breaks. 

Treatment may include laser surgery or cryopexy (essentially freezing the tear), both of which 

can be performed on an outpatient basis. Vitrectomy, a procedure in which the vitreous fluid and 

scar tissue are removed from the eye and replaced with clear liquid or other substitute, or the 

attachment of a scleral buckle (which maintains the appropriate shape of the eye and brings the 

layers of the eye back together) may require an inpatient stay. 

Three studies examined the incidence of retinal detachment or retinal breaks. In the 

study by Holland et al. (1992), comparisons of the 1-year incidence of rhegmatogenous retinal 
10

detachment were made between the inpatient setting and the hospital outpatient department 

setting, with a higher incidence of detachment in the outpatient setting (2.3%) than in the 

inpatient setting (1.0%) (N.S.). Javitt and colleagues (1992; 1994) examined the probability of a 

retinal break or retinal detachment following cataract surgery in a Medicare population. In one 

study (Javitt, Tielsch et al. 1992), the 36-month cumulative probability of retinal detachment was 

0.8% after cataract surgery alone and 1.6% after cataract surgery and capsulotomy (p<0.0001). 

The 36-month cumulative probability of a retinal break was considerably smaller – 0.34% 

overall. In a later study, Javitt et al. (1994) compared the incidence of retinal detachment in a 

cohort of inpatient cataract surgery patients with the same in a cohort of cataract surgery patients 

for whom the surgery took place in an inpatient, hospital outpatient department, ambulatory 

surgical center, or physician’s office setting. In this study, the 36-month cumulative probability 

of retinal detachment was 0.81% for the sample across settings and 0.72% in an earlier inpatientonly sample. In both studies by Javitt et al. (1992, 1994), the following characteristics were 

associated with the 36-month cumulative probability of retinal detachment: capsulotomy 

performed, younger age, white race, and male. In the 1994 study by Javitt and colleagues, the 

authors also identified having a diagnosis of diabetes as a risk factor for retinal detachment. 

Endophthalmitis: Endophthalmitis is an intraocular infection that is almost always 

bacterial in origin. Most patients present with infection within the first two weeks following 

cataract surgery. It is a serious medical condition that can result in vision loss if left untreated 

for an extended period of time. The usual treatment is with antibiotics and injected steroids are 

used less often. Vitrectomy may be appropriate in the most acute cases. Hospitalization is 

generally required. 

Two studies examined the incidence of endophthalmitis following cataract surgery 

(Javitt, Street et al. 1994; Bohigian 1999). Javitt et al. (1994) identified a 0.055% 1-month 

cumulative probability of hospitalization for endophthalmitis in a cohort of Medicare 

beneficiaries who had cataract surgery (across all sites of care). The 1-month cumulative 

probability in an associated inpatient-only sample was 0.085% (p=0.01 for comparison across 

sites). The 1-year cumulative probability of hospitalization for endophthalmitis was 0.081% in 

the Medicare beneficiary cohort (across sites) and 0.12% in the inpatient setting (p=0.01). 

Bohigian (1999) found a 0.05% incidence of culture-positive endophthalmitis in the 15 days 

post-surgery in a cohort that had cataract surgery in an ambulatory surgical center. The study by 

Bohigian did not indicate whether these cases of infection lead to hospitalization. Neither of 

these studies examined the association of patient characteristics with the incidence of 

endophtalmitis. 

Opacified Posterior Lens Capsule/Capsulotomy: While capsulotomy is sometimes 

performed following cataract surgery, it is not clear that it reflects an underlying complication of 

the surgery, as little is known about its causes. In some cases, the posterior portion of the 

capsule becomes cloudy after cataract surgery. If the cloudiness begins to impair vision, a 

capsulotomy is performed in which a laser is focused on the center of the cloudy capsule, 

creating an opening to allow light rays to pass through. This procedure is generally performed 

on an outpatient basis. 

Two studies examined the incidence of opacified posterior lens capsules (which can lead 

to capsulotomy) or the incidence of capsulotomy (Holland, Earl et al. 1992; Javitt, Tielsch et al. 

1992). In Holland et al. (1992), the authors found a 1-year incidence of opacified posterior lens 

capsules in 5.0% of all inpatient cataract surgery patients in their study compared to 5.7% of 

those whose surgery took place in a hospital outpatient department (N.S.). Javitt and colleagues 
11

(1992) reported a 3-year cumulative probability of capsulotomy following cataract surgery in a 

sample of Medicare beneficiaries of 24.0%; approximately 2.6% of these capsulotomies occurred 

in the first 30 days following cataract surgery. Neither study examined patient characteristics 

associated with an opacified posterior lens capsule or capsulotomy. 

Other Capsule Complications: Three studies also identified other complications 

associated with the capsule. Holland et al. (1992) examined the incidence of intra-operative 

posterior lens capsule tears with vitreous loss; a 2.3% incidence was identified in an inpatient 

sample as compared to 2.0% in a hospital outpatient setting (N.S.). Ahmed and colleagues 

(2002) identified a 5.0% incidence of posterior capsule rupture during cataract surgery in an 

ambulatory surgical center. Corey and colleagues (1998) observed a 0.8% average incidence of 

posterior capsule rupture during surgery in a hospital outpatient department. The early 

experience among surgeons in this study was associated with a 1.0% incidence of posterior 

capsule rupture; however, the incidence dropped to 0.5% as the surgeons in this study gained 

more experience. 

Other Complications: Several other complications were reported in the clinical studies 

we abstracted. Several of these additional complications are considered rare but serious and in 

some cases, may require an inpatient stay and/or follow-up surgery to correct. Among them are 

iris adherence (Holland, Earl et al. 1992), wound dehiscence (Holland, Earl et al. 1992), wound 

leak (Corey and Olson 1998), and nuclear fragment in the angle (Corey and Olson 1998). Each 

of these complications are or can be very serious and may require a return to the operating room 

and are likely capable of being tracked with administrative data. 

Additional potentially serious complications that are often treated with medications and 

may require a return visit to the physician’s office or some other outpatient setting include 

cystoid macular edema, persistent iridocyclitis and poor ocular motility; however, it is not clear 

that these complications can be tracked in administrative data. Cystoid macular edema (Holland, 

Earl et al. 1992) is usually temporary and often treatable with topical or peri-bulbar steroids but 

if left untreated, can cause permanent vision loss. Persistent iridocyclitis (Holland, Earl et al. 

1992) is uncommon but is generally treated with steroids. Generally poor ocular motility 

(Kollarits, Jaweed et al. 1998) is temporary and returns as anesthesia wears off. It is a rare 

condition but may be treatable. 

Other complications that are generally less serious or very common to the cataract 

procedure or can be managed intra-operatively include subconjunctival hemorrhage (Ahmed, 

Zabriskie et al. 2002), eyelid hematoma (Ahmed, Zabriskie et al. 2002), ocular hypertension 

(Holland, Earl et al. 1992), corneal edema (Holland, Earl et al. 1992), iris trauma (Holland, Earl 

et al. 1992), zonular dehiscence (Corey and Olson 1998), vitreous loss (Corey and Olson 1998), 

and pain (Kollarits, Jaweed et al. 1998; Harman 2000; Ahmed, Zabriskie et al. 2002). These 

complications are likely not available for tracking in administrative data. 

Complications Unrelated to the Eye: Anesthesia Complications 

 Four studies were identified that examined complications related to anesthesia during 

cataract surgery (Mayer and O'Connor 1993; Ascaso, Ayala et al. 1997; Rosenfeld, Litinsky et 

al. 1999; Harman 2000). Mayer (1993) described adverse events associated with a retrobulbar 

anesthetic injection (local anesthesia) in a single case report for a cataract surgery performed in 

an ambulatory surgical center. The patient who was the subject of the case report experienced 

significant cardiovascular events following the administration of anesthesia including 
12

hypertension, cardiomegaly, atrioventricular block and left anterior fascicular block. The patient 

also experienced respiratory arrest. 

In another study, Rosenfeld and colleagues (1999) examined the need for intervention by 

an anesthesiologist for patients who received peribulbar anesthesia for cataract surgery in an 

ambulatory surgical center. Interventions ranged from reassurance; physical restraint; 

supplemental peribulbar or retrobulbar injections; intravenous sedation; assisting respirations; 

and antihypertensive, antiarrhythmic, or other agent. Rates of intervention were high preoperatively (20.4%) and intra-operatively (21.9%), but relatively low post-operatively (2.7%). 

The risk of intervention was higher among patients with significant co-morbidity including 

hypertension, pulmonary disease, renal disease, and cancer. The study did not specify the type 

of intervention required. 

Harman (2000) examined the sedation effect on blood pressure in hypertensive and nonhypertensive patients undergoing cataract surgery in an ambulatory surgical center. Both 

hypertensive and non-hypertensive patients who received sedation (Lorazepam) experienced 

decreases in systolic and diastolic blood pressure during surgery as compared to those who 

received no sedation (no statistical tests reported). The changes in blood pressure were more 

common among hypertensive than non-hypertensive patients however. 

 Ascaso and colleagues (1997) examined the frequency of post-operative nausea and 

vomiting associated with anesthesia and explored in a randomized controlled trial the efficacy of 

selected anti-emetics in reducing the frequency of such episodes in cataract patients. The 

incidence of nausea or vomiting in the 24-hour period after anesthesia administration was over 

20% in the placebo group in this study relative to less than 3% among those who were given 

Ondanesetron to reduce such symptoms. 

Complications Unrelated to the Eye: Medical Complications, Hospitalizations, and Death 

 Only one study examined the probability of significant medical events resulting in 

hospitalization or death following cataract surgery. Katz et al. (2001) followed cataract patients 

for seven days post-surgery in inpatient and ambulatory surgical center settings (not 

distinguished by setting in results) to examine intra- and post-operative medical complications 

including cardiovascular and other medical events, hospitalization, and death. These 

complications are very rare and vary by type of anesthesia employed during cataract surgery. 

The most common medical complications were related to the cardiovascular system (e.g., 

myocardial infarction, ischemia, hypertension, hypotension, etc.) with a 2.6% incidence of intraoperative cardiovascular events and a 0.58% incidence of post-operative cardiovascular events. 

The post-operative incidence of cerebrovascular events was 0.04% (no intra-operative events). 

Intra-operative incidence of pulmonary events was 0.05% and post-operative incidence of such 

events was 0.05% as well. Upper respiratory events during cataract surgery were extremely rare 

(0.01%) and were 0.17% post-operatively. Intra-operative medical events varied by the type of 

anesthesia administered during the cataract surgery, ranging from 0.13% among patients who 

received a topical anesthesia and oral sedatives to 4.26% among patients who received topical 

anesthesia, IV sedatives and opioids. Complications were generally higher with injected 

anesthesia and when opioids or hypnotics were used in conjunction with topical or injected 

anesthesia compared with other anesthesia/sedation combinations. 

In total, Katz and colleagues (2001) found that intra-operative medical complications lead 

to hospitalization in 0.04% of all cataract surgery patients and post-operative medical 
13

complications lead to hospitalization in 0.3% of all cataract surgery patients. The seven-day 

incidence of post-operative mortality was 0.04% (no intra-operative mortality). The intra- and 7-

day post-operative incidence of hospitalization and death also varied by type of anesthesia 

employed during the cataract surgery although the variation was small, ranging from 0% among 

those who received injection anesthesia and oral sedatives to 0.67% among those who received 

opioids and hypnotics in conjunction with injected anesthesia. 

Data Sources for Measuring Variation Across Settings 

 Few studies discussed patient characteristics beyond basic cohort information (Medicare 

age 65, sex, etc) that can be developed from the administrative data. Diabetes is one condition 

that may be important to measure and should be identifiable in the administrative data as well. 

The majority of studies selected for abstraction draw from the medical record, operative reports, 

and patient or provider questionnaires for reporting process measures and complications of 

cataract surgery. 

With regard to complications, two studies using specifically Medicare claims (Javitt, 

Tielsch et al. 1992; Javitt, Street et al. 1994), demonstrating the ability to track retinal 

detachment, retinal break, and hospitalization for endophthalmitis using administrative data. It is 

not clear however if we are able to track endophthalmitis that does not lead to hospitalization in 

administrative claims. In addition to those listed above, we may also be able to track any 

significant medical events that lead to hospitalization using administrative data. The challenge to 

such an identification is selecting an appropriate timeframe in which to consider hospitalization 

the result of the procedure as opposed to some intervening event. We can also potentially 

identify deaths that occur in relation to the procedure; however, attributing the death directly to 

the cataract procedure will be difficult. Katz and colleagues (2001) followed patients for seven 

days post-procedure. The authors tracked cardiovascular and other significant medical events as 

well as hospitalizations and deaths post-procedure. They were able to distinguish between 

intraoperative and postoperative events. Using claims data, we may be limited in defining events 

occurring intraoperatively and postoperatively if they occur on the same day. Javitt et al. (1992; 

1994) follow patients for up to three years to study the rate of capsulotomy, retinal break and 

retinal detachment, and hospitalization due to endophthalmitis. Retinal detachment, retinal 

break, and opacified posterior lens capsules leading to capsulotomy may occur months or even 

years following the cataract surgery. It is not clear however if their occurrence is a sign of poor 

quality when it occurs later rather than in the more immediate period following surgery. Javitt et 

al. (1994) also examines the rate of hospitalization due to endophthalmitis for both the 1-month 

and 12-month post-procedure time period, demonstrating that this complication can be monitored 

in the short term. 

With regard to procedure characteristics, the literature discusses highlights some aspects 

of the procedure that may be identifiable by HCPCS code (cataract surgery alone and cataract 

surgery and capsulotomy). The type of anesthesia care may be an important factor affecting the 

length of the surgical procedure and may be analyzed through administrative data only to a 

limited extent. Surgical time is not recorded in the administrative data but anesthesia time is 

reported. Full information on type of anesthesia used is not routinely collected because 

anesthesia supplies are bundled in the facility payment. 
14
15

SECTION 4. CRANIAL AND SPINAL MAGNETIC RESONANCE (MR) IMAGING 

 In this section, we summarize the findings from the literature regarding structure/process 

and complication measures of MR imaging of the brain. Cranial and spinal MRI may be 

performed with or without contrast. Contrast agents can help providers detect and characterize 

lesions. In the United States, the Food and Drug Administration (FDA) has approved several 

contrast agents for cranial and spinal MR imaging. These agents include gadolinium chelates, 

include Magnevist (gadopentetate dimeglumine or GD DTPA), ProHance (gadoteridol or Gd 

HP-DO3A), Omniscan (gadodiamide or Gd DTPA-BMA), and Optimark (gadoversetamide or 

Gd DTPA-BMEA). Magnevist is an ionic agent, whereas ProHance, Omniscan, and Optimark 

are non-ionic agents (Runge 2001). Feridex and Teslascan, which are not gadolinium-based 

agents, are two other intravenous contrast agents used in conjunction with MR imaging, but these 

agents are primarily used for hepatobiliary rather than cranial/spinal imaging. Based on analyses 

performed in an earlier task of this project, over half of all MR imaging of the brain performed 

on an outpatient basis took place in a hospital outpatient department (51.7%) and approximately 

36.7% took place in a physician’s office. An additional 11.6% of all MR imaging of the brain 

occurred in an IDTF. 

 In general, MR imaging is associated with relatively few safety concerns, except in 

patients with certain types of cardiac pacemakers, metallic vascular aneurysm clips, 

ferromagnetic devices, and metallic fragments in the orbit, and in patients with claustrophobia. 

Because of safety concerns, MR imaging is contraindicated for some patients with metallic 

foreign bodies or implants. Most patients without contraindications who undergo non-contrast 

cranial/spinal MR imaging tolerate the procedure without experiencing adverse events. Patients 

without contraindications who undergo contrast-enhanced MRI also have few adverse reactions. 

When patients do experience complications, the complications can be grouped into the 

following categories: clinical symptoms and signs, changes in vital signs, changes in other parts 

of the physical exam, and changes in laboratory values. Clinical symptoms and signs include, 

but are not limited to nausea, vomiting, injection site pain or warmth, skin lesions vasodilatation, 

headache, metallic taste, dizziness, flushing, and anaphylactoid reaction. In clinical trials, 

researchers have also evaluated patients for changes in electrocardiogram and 

electroncephalogram studies following MR imaging. It was not clear in our review of the 

literature whether the complications could be attributed to the MR procedure or contrast in part 

because the studies included in this review did not have control groups receiving no MR imaging 

and/or contrast. 

 Tables summarizing the selected clinical studies are in Appendix A.2. The text that 

follows summarizes our understanding of outcomes of the procedure. When possible, the 

outcomes are stratified by patient population. Because most studies did not specify the site of 

care, we cannot comment on any differences that might be detected in structural measures or 

complications across sites of care. At the end of this section, we address the availability of data 

to compare structural measures and complications across sites of care. 

Literature Search Results 

Figure 4.1 summarizes the literature search results for the clinical studies on cranial and 

spinal MR imaging. A total of 221 abstracts and/or titles were identified through our search 

procedures described in Section 2. In the first stage of review, abstracts or titles were rejected if 
16

the study setting was clearly an inpatient setting or if the study focus was not related to structure, 

process or complications of the procedure. We identified 47 titles/abstracts for further review 

and abstraction. Of this subset of articles, 34 (72.3%) were further excluded for the following 

reasons: the study was based on a non-U.S. population, the focus was on inpatient setting (but 

not evident during first stage of review), the study described a procedure other than MR imaging, 

or the paper was a review article or meta-analysis. Of the 13 articles selected for abstraction, one 

article reported on structural aspects of the procedure, and all articles reported on outcomes or 

complications directly related to the procedure. 

Figure 4.1 Search Results for the Cranial and Spinal MR Imaging Review 

Titles/Abstracts Retrieved from 

Literature Search

N = 221

Papers Retrieved from 

Title/Abstract Review

N = 47

Papers Accepted for 

Abstraction 

N=13

Titles/Abstracts 

Excluded

N = 172

Articles Excluded (N=34)

• Foreign Article (21, 

62%)

• Other Setting of Care 

(1, 3%)

• No Process Measures or 

Complications Reported 

(0, 0%)

• Review/Meta-Analysis 

(10, 29%)

Limitations of the literature review include omission of studies that focused on non-U.S. 

populations. However, since the purpose of the project is to evaluate variation in safety across 

different outpatient sites of care and to identify characteristics that might impact a provider’s 

decision to perform or refer a patient to a particular outpatient site, the relevance of non-U.S. 

based studies, which may have been performed in countries with healthcare systems that are very 

different from the U.S. healthcare system, is questionable. A second limitation involves the 

strength of study design of articles included in the review. Only two studies were randomized 

controlled trials and the randomization involved type of gadolinium contrast, not setting of care. 

Setting of Care 

 Of the 13 studies considered, none specified whether the study took place in an 

ambulatory surgical center, physician’s office, or hospital outpatient department. One study 

(Murphy, Szopinski et al. 1999) included “freestanding clinics,” but the study was not limited to 

MR imaging performed in “freestanding clinics” only. 

Sample Description 

 The selected studies did not consistently provide descriptive information about the patient 

samples included in their reports. Most studies provided mean age (9 out of 13 articles) and 

gender (10 out of 13 articles). Inclusion criteria and exclusion criteria varied, making 
17

comparison of the samples difficult. No studies specifically selected a sample comprised mostly 

or entirely of Medicare-eligible population age 65 and older. Only three studies examined the 

association of patient characteristics with complications of care (Runge and Parker 1997; Sze, 

Brant-Zawadzki et al. 1993; Nelson, Gifford et al. 1995). 

Structure Measures 

 Only one study reported structure measures of quality of care (Murphy, Szopinski et al. 

1999). These structure measures included the following: precautions in place at institution for 

patients with history of reaction to iodinated contrast material, precautions in place at institution 

for patients with history of reaction to gadolinium-based contrast agents, patients undergoing 

MR imaging observed by advanced cardiac life support-certified healthcare worker, patients 

undergoing imaging observed by basic life support-certified healthcare worker, and 

arrangements in place with a code team to manage emergencies. Ten out of the 24 (42%) 

freestanding clinics reported having arrangements in place with a code team to manage 

emergencies. 

Complications/Adverse Events Related to Cranial/Spinal MR Imaging 

 All 13 articles reported complications associated with cranial/spinal MR imaging. No 

articles focused on effects of sedation. In this section, we summarize the major and minor 

complications reported in the literature related to cranial/spinal MR imaging. Most studies 

focused on contrast-enhanced MR imaging. No studies compared complication rates across the 

three settings of interest. 

Signs and symptoms: Studies reported a variety of adverse signs and symptoms in the 

setting of MR imaging with contrast administration. Some studies classified these adverse 

events as mild, moderate, or severe, while others listed the occurrence of signs and symptoms 

without specifying the severity. One study used the following taxonomy for adverse events: 

mild (hives, diffuse erythema, skin irritation), moderate (respiratory symptoms), and severe 

(respiratory distress and facial or airway edema) (Murphy, Szopinski et al. 1999). However, 

most studies did not use this taxonomy. 

Four studies (Nelson, Gifford et al. 1995; Olukotun, Parker et al. 1995; Murphy, 

Szopinski et al. 1999; Grossman, Rubin et al. 2000) specifically labeled reactions as severe or 

serious reactions, but the severe or serious reactions were not uniform across the four studies. 

Nelson et al. (1995) reported one case of tent herniation and one case of severe vertigo, but did 

not consider either of these reactions to be related to MR imaging. Grossman et al. (2000) 

reported that five patients (1.9%) experienced severe events (three reports of headache, one 

report of chest pain, one report of leg cramps, one report of urinary tract infection) when exposed 

to gadoversetamide and four patients (3.8%) experienced severe events (one report of leg 

cramps, one report of back pain, one report of vasospasm, one report of vasodilatation, and one 

report of taste perversion) when exposed to gadopentetate dimeglumine. Olukoton et al. 

(Olukotun, Parker et al. 1995) reported two severe adverse events (one ruptured aneurysm, and 

one vasospastic event). Murphy et al. (1999) reported five cases (0.001%) of severe reactions 

(respiratory distress or facial/airway edema) for gadopentetate dimeglumine and eleven cases 

(0.017%) for gadoteridol. In none of the studies was a control group present that did not receive 

contrast or that did not undergo MR imaging. 
18

A few of the review articles also provided information on severe adverse symptoms or 

signs associated with MR imaging. A review article by Carr (1994) noted an incidence of 

anaphylactoid reactions associated with gadopentetate dimeglumine to be 1 in 350,000 to 

450,000. Runge (2000) reviewed the safety of approved MR contrast agents reported a study 

that found the incidence of severe anaphylactoid reactions associated with gadopentetate 

dimeglumine to be 2 in 21,000. In their summary of clinical trials of gadopentetate dimeglumine 

performed between 1984 and 1988, Goldstein et al. (1990) report four cases of seizures, with 

three out of four patients having a history of seizures and the fourth patient having a history of 

bifrontal headaches and acquired immunodefiency syndrome. Lee et al. (2000) reviewed the 

literature on contrast agents used in ophthalmology and report 0.1% seizure activity and 6% EEG 

changes associated but not necessarily causally related to gadolinium. 

Three studies that met inclusion criteria for the literature review reported death: 1 out of 

1709 patients died (Olukotun, Parker et al. 1995); 2 out of 2,481 (Runge and Parker 1997); 1 out 

of 439 (Sze, Brant-Zawadzki et al. 1993), but these studies were not randomized clinical trials. 

The authors of two of the studies note that the deaths were deemed unrelated to the MR 

imaging/contrast. For example, Sze et al. (1993) note that the death in their study occurred two 

days after injection of gadodiamide and that no changes in safety measurements obtained 

immediately and 24 to 36 hours after the procedure occurred. The safety of MR imaging 

contrast in pregnant women is unclear, since well-controlled studies using human subjects are 

lacking. Animal studies have showed adverse effects on fetuses (Runge 2000). 

 Mild and moderate adverse symptoms and signs were not uniformly reported. The table 

in Appendix A.2 provides a summary of the frequency or incidence of various symptoms and 

signs reported, including but not limited to nausea, vomiting, headache, pain, urticaria, other 

rashes, paresthesia, tachycardia, dry mouth, dysgeusia, dizziness, muscle cramps. According to a 

review by Runge (2000), nausea and hives occur in comparable numbers for all currently 

approved MR imaging contrast agents, with urticaria (itchy skin rash) occurring in less than 1% 

of patients. Among iodinated agents, high osmolality (concentration of the contrast in the blood) 

may impact the level of pain and tissue necrosis associated with extravasation (forcing contrast 

out of the blood vessels) (Runge 2000). 

 Three studies examined patient characteristics associated with adverse signs or 

symptoms. Sze and colleagues (1993) found that age, sex, and contrast volume were not related 

to any type of adverse event. Nelson and colleagues (1995) found that a history of asthma was 

associated with higher rate of adverse reactions (3.7% as compared to 2.4% among those with no 

asthma history and 2.0% among those with unknown asthma history). Runge and Parker (1997) 

found a trend toward lower incidence in pediatric and elderly populations (although not 

statistically significant); those age 18 to 60 were more likely to have an adverse event (7.9%) as 

compared to those less than 18 years (3.4%) and older than 60 years (4.4%). Women were also 

slightly more likely to have an adverse event than men (7.4% vs. 5.8%). 

Change in vital signs: Nine studies (Runge, Bradley et al. 1991; Carvlin, De Simone et 

al. 1992; Yuh, Engelken et al. 1992; Sze, Brant-Zawadzki et al. 1993; Zoarski, Lufkin et al. 

1993; Olukotun, Parker et al. 1995; Runge and Parker 1997; Grossman, Kuhn et al. 1998; Runge, 

Armstrong et al. 2001) commented on presence or absence of change in vital signs. Seven of the 

studies reported no clinically significant changes or in one study, a “low incidence of clinically 

remarkable changes” (Runge and Parker 1997). Olukotun et al. (1995) reported one case of 

bradycardia in a patient with previously undetected intermittent atrioventricular block and one 

case of hypotension that resolved within two hours. Grossman et al. (1998) noted some 
19

statistically significant changes, but no clear pattern. A review by Goldstein et al. (1990) 

summarizing results from clinical trials conducted in the United States between 1984 and 1988 

of MR imaging with gadopentetate dimeglumine reported 3 out of 1,068 cases of hypotension, 

but overall no clinically significant differences in vital signs between placebo and gadopentetate 

dimeglumine groups were observed. 

Change in physical exam (excluding vital signs): Four studies commented on presence 

or absence of changes in physical exam (Runge, Bradley et al. 1991; Yuh, Engelken et al. 1992; 

Sze, Brant-Zawadzki et al. 1993; Yuh, Fisher et al. 1994; Runge and Parker 1997). One of the 

studies only reported on the presence or absence of changes in the neurological exam (Sze, 

Brant-Zawadzki et al. 1993). Two of the five studies reported no changes in the complete 

physical exam (Yuh, Engelken et al. 1992; Runge and Parker 1997). Two of the five studies 

reported some changes in the physical exam: in the study by Runge et al. (1991), the authors 

noted that twenty-six patients out of 411 had changes in their physical exam and 16 out of 26 of 

the patients had improvement in their exam. The authors note that none of the findings were 

attributed to contrast administration. Yuh et al. (1994) report that one patient, who was 

recovering from surgery at the time of the post-MRI examination, had a change in the physical 

exam. 

Change in laboratory values: Ten studies reported whether or not patients experienced 

changes in laboratory values (Runge, Bradley et al. 1991; Carvlin, De Simone et al. 1992; Yuh, 

Engelken et al. 1992; Sze, Brant-Zawadzki et al. 1993; Zoarski, Lufkin et al. 1993; Yuh, Fisher 

et al. 1994; Olukotun, Parker et al. 1995; Runge and Parker 1997; Grossman, Kuhn et al. 1998; 

Runge, Armstrong et al. 2001). Five of the studies reported no clinically significant changes 

(Yuh, Engelken et al. 1992; Yuh, Fisher et al. 1994; Runge and Parker 1997; Runge, Armstrong 

et al. 2001). The overall number of subjects with lab changes in a study by Yuh et al. (1992) 

was nine out of 31 patients. Zoarski et al. (1993) reported that 19 patients out of 133 patients 

who underwent MR imaging experienced changes in lab values. The authors attributed 2 out of 

133 (1.5%) to MR imaging. Thirty-six patients (41.9%) of patients in Carvlin et al.’s (1992) 

study experienced lab changes, but none were clinically significant. Five studies all reported 

changes in serum iron. The type of change (increase versus decrease) in serum iron levels varied, 

and some studies did not specify whether the change reflected an increase or a decrease in serum 

iron levels. These remaining four studies did not provide consistent information about other 

laboratory studies, including little or no information about serum chemistries, white blood cell 

counts, hemoglobin, platelet count, liver function tests, serum creatinine, and urinalysis. 

Changes in electrocardiogram: Three studies (Carvlin, De Simone et al. 1992; 

Olukotun, Parker et al. 1995; Runge, Armstrong et al. 2001) reported no significant changes in 

electrocardiogram studies. The remaining studies did not report or did not perform 

electrocardiogram studies. 

Safety Concerns Not Covered in Abstracted Literature 

 Performing MR imaging on patients with certain metallic implants and devices or 

metallic fragments in the orbit may be associated with adverse consequences, usually if the 

foreign body is made of ferromagnetic materials. In a literature review of the safety of MR 

imaging in patients with implants and devices, Shellock (2002) distinguishes between metallic 

implants and devices that are MR “safe” versus MR “compatible,” with “safe” meaning that the 

MR environment poses “no additional risk to the patient or other individual, but may affect the 
20

quality of the diagnostic information and “compatible” meaning that the MR environment poses 

no safety concerns, does not affect the quality of MR imaging, and does not undergo altered 

operations as a result of the MR conditions. The author adds that information about the safety 

and compatibility of many implants and objects is readily available, although many of the 

evaluations were performed under systems that used a 1.5 Tesla field rather than higher 3.0 Tesla 

fields that may now be used. Ferromagnetic fragments in the orbit may move during MR 

imaging. Some studies suggest that this movement poses high risk for ocular injury resulting in 

hyphema and increased intraocular pressure, while others do not support this conclusion (Ta and 

Bowman 2000). 

Data Sources for Measuring Variation Across Settings 

 Most studies selected for abstraction did not specify data source. Some studies assessed 

adverse events via provider questionnaire, patient questionnaire, or both. No studies used claims 

data. While administrative data can be used to track basic patient demographic and health status 

characteristics, one characteristic of particular interest – metallic fragments in the orbit – cannot 

be tracked. It may be possible to track history of seizures and history of reaction to gadoliniumbased contrast agents, but the feasibility of having sufficient history is an issue. With respect to 

complications, it may be possible to track mortality however, attributing death to the procedure 

would be difficult. Administrative data may be useful in tracking significant medical events 

such as respiratory distress, anaphylaxis, seizure, hypotension, increased intraocular pressure, but 

just as stated above, our ability to attribute events such as respiratory distress, seizure, increased 

intraocular pressure, or hypotension to MR imaging will be difficult. 

With respect to procedure characteristics, the administrative data may be used to track 

whether contrast media were used. Differences in structural processes such as whether patients 

undergoing MR imaging are observed by advanced cardiac life support-certified healthcare 

worker cannot be observed in the administrative claims data; however, there may be other 

administrative information, such as licensure and accreditation data, that could be informative in 

this regard. 

 
21

SECTION 5. COLONOSCOPY 

 In this section, we summarize the findings from the literature regarding process and 

outcome/complication measures of colonoscopy procedures. Colonoscopy is a commonly 

performed procedure used to screen for colorectal cancer but it is also used to diagnose the 

causes of unexplained changes in bowel habits, which may be caused by cancer or some other 

disease/condition. Therapeutic colonoscopies can be performed to remove polyps and to treat 

bleeding in the colon. Generally, the procedure is performed under some level of sedation and/or 

with pain medication. Studies provide evidence that colonoscopy is effective in reducing the 

incidence of colon cancer in populations at high risk (Winawer, Zauber et al. 1993; Citarda, 

Tomaselli et al. 2001) and recently published updated guidelines for colorectal cancer screening 

recommend that colonoscopy be performed every ten years beginning at age 40 (Winawer, 

Fletcher et al. 2003). Medicare modified its policy on covering colonoscopy in 2001 to cover the 

procedure every ten years for all Medicare beneficiaries age 50 and over. This policy change 

expanded on the earlier coverage rule that one had to be “high risk” for Medicare to cover the 

colonoscopy procedure. Those who are deemed at high risk are eligible for colonoscopy 

screenings more often under Medicare. 

The colonoscopy procedure can take place in most outpatient settings; however, it is most 

commonly performed in a hospital outpatient department or ambulatory surgical center. Based 

on analyses performed in an earlier task of this project, among those colonoscopy procedures 

performed on an outpatient basis, 70.6% were performed in a hospital outpatient department, 

24.9% were performed in an ambulatory surgical center, and only 4.3% were performed in a 

physician’s office. 

Most colonoscopies are uncomplicated and effectively diagnose and treat various 

gastrointestinal conditions. In some cases however, intra-operative and post-operative 

complications arise including most commonly perforation, bleeding, pain, and abdominal 

discomfort. Complications unrelated to the colon but often associated with sedation: oxygen 

desaturation, hypertension, hypotension, arrhytmias, and bradycardia. Complications of the 

colonoscopy procedure may lead to hospitalization and in rare cases, death. 

 Appendix A.3 presents summaries of the selected clinical studies. In the following 

sections, we summarize our understanding of outcomes of the procedure in terms of variation 

across sites of care, any variation in the patient populations cared for in each setting, and a 

description of the quality measures and what, if any, differences can be detected in process 

measures or complication across site of care. Finally, we address the availability of data to 

compare process measures and complications across sites of care. 

Literature Search Results 

Figure 5.1 describes our results of the literature search for clinical studies on 

colonoscopy. A total of 312 abstracts and/or titles were identified through our search procedures 

described in Section 2. We identified 63 titles/abstracts for abstraction based on our review of 

the titles and abstracts. Of this subset of articles, 39 (61.9%) were further excluded. Articles 

were excluded for the following reasons: study setting was not an outpatient setting or setting 

was unclear, 10 (25.6%); the study was based on a non-U.S. population, 19 (48.7%); no process 

measures or complications were reported relating to the procedure, 4 (10.3%), or the study was 

not retrievable, 2 (5.1%). Meta-analysis/review articles, 4 (10.3%), were not abstracted but 
22

information from these papers is summarized where relevant in the text that follows. Of the 24 

articles selected for abstraction, 16 reported on the process of the procedure in addition to 

reporting on outcomes or complications directly related to the procedure. 

One of the major limitations of the literature review was the exclusion of studies that 

focused on non-U.S. populations, as almost half of all studies were from foreign sources. As we 

noted in the previous chapter, since the purpose of the project is to evaluate variation in safety 

across different outpatient sites of care and to identify characteristics that might impact a 

provider’s decision to perform or refer a patient to a particular outpatient site, the relevance of 

non-U.S. based studies, which may have been performed in countries with healthcare systems 

that are very different from the U.S. healthcare system, is questionable. Only one study 

identified for review was a randomized controlled trial; and the study population was 

randomized to method of sedation rather than setting of care. 

Figure 5.1 Search Results for the Colonoscopy Review 

Titles/Abstracts Retrieved from 

Literature Search

N = 312

Papers Retrieved from 

Title/Abstract Review

N = 63

Papers Accepted for 

Abstraction 

N=24

Titles/Abstracts 

Excluded

N = 249

Articles Excluded (N=39)

• Foreign Article (19, 

48.7%)

• Other Setting of Care 

(10, 25.6%)

• No Process Measures or 

Complications Reported 

(4, 10.3%)

• Review/Meta-Analysis 

(4, 10.3%)

• Unable to Locate Article 

(2, 5.1%)

Setting of Care and Provider of Service 

 Of the 24 studies considered, 12 were based in hospital outpatient departments (Rosen, 

Bub et al. 1993; Shiffman, Farrel et al. 1994; Poser and Ladik 1995; Pierzchajlo, Ackermann et 

al. 1997; Galandiuk and Ahmad 1998; Wexner, Forde et al. 1998; Zubarik, Fleischer et al. 1999; 

Anderson, Pasha et al. 2000; Timothy, Hicks et al. 2001; Nelson, McQuaid et al. 2002; Bini, 

Firoozi et al. 2003; Cotton, Connor et al. 2003). Three studies examined the colonoscopy 

procedure in ambulatory surgical centers (Waye, Lewis et al. 1992; Korman, Overholt et al. 

2003; Walker, McIntyre et al. 2003) and one combined data from procedures performed in an 

ASC and hospital outpatient department. Four studies were based solely in a physician’s office 

(Godreau 1992; Rodney, Dabov et al. 1993a; Rodney, Dabov et al. 1993b; Newcomer, Shaw et 

al. 1999) and one incorporated data from hospital outpatient departments and physicians’ offices 

(Hopper, Kyker et al. 1996). Two studies incorporated data on colonoscopies from hospital 

inpatient and outpatient facilities (Rex, Imperiale et al. 1999; Clarke, Jacobson et al. 2001), and 

one study examined complications of colonoscopy across all care settings (inpatient and 

outpatient hospital settings, ambulatory surgical centers, and physicians’ offices) using the 
23

Surveillance, Epidemiology, and the End Results (SEER) database linked to Medicare 

administrative data (Gatto, Frucht et al. 2003). 

 Gastroenterologists were the most commonly cited provider of colonoscopy in the 

selected studies. In four of the nine studies in which gastroenterologists performed 

colonoscopies, they were the only provider type listed (Rex, Imperiale et al. 1999; Anderson, 

Pasha et al. 2000; Nelson, McQuaid et al. 2002; Bini, Firoozi et al. 2003). Gastroenterologists 

were co-listed with surgeons in two studies (Rosen, Bub et al. 1993; Zubarik, Fleischer et al. 

1999), with surgeons and surgical residents in one study (Galandiuk and Ahmad 1998), with 

endoscopists in one study (Korman, Overholt et al. 2003), and with a nurse in one study (Walker, 

McIntyre et al. 2003). Surgeons were the only referenced provider in two studies (Wexner, 

Forde et al. 1998; Timothy, Hicks et al. 2001) and endoscopists were the only referenced 

provider in two studies as well (Waye, Lewis et al. 1992; Cotton, Connor et al. 2003). Five of 

the 23 selected studies identified family practice physicians as the colonoscopy provider 

(Godreau 1992; Rodney, Dabov et al. 1993a; Rodney, Dabov et al. 1993b; Hopper, Kyker et al. 

1996; Pierzchajlo, Ackermann et al. 1997). Six studies did not specify the service provider 

(Shiffman, Farrel et al. 1994; Poser and Ladik 1995; Lugay, Otto et al. 1996; Newcomer, Shaw 

et al. 1999; Clarke, Jacobson et al. 2001; Gatto, Frucht et al. 2003). 

Sample Description 

 Age and gender were the most commonly reported sample characteristics in the studies 

reviewed. Because a baseline colonoscopy is generally recommended at the age of 50 in average 

risk individuals (Winawer, Fletcher et al. 2003), the average age of the patients in the selected 

study samples was generally over 50. Few studies examined the traditional Medicare-eligible 

(age 65 and older) population specifically. One study included only the oldest old (age 85 and 

older) in the sample (Clarke, Jacobson et al. 2001) and in the study by Gatto and colleagues 

(2003), the authors limited the study to those with at least one colonoscopy billed to Medicare 

during the study time period. Gender of the study samples varied from study to study but where 

reported, women generally comprised slightly more than half the study sample. 

Only four studies examined the association of patient characteristics with complications 

of care; two considered patient characteristics associated with perforation (Gatto, Frucht et al. 

2003; Korman, Overholt et al. 2003), one examined patient characteristics associated with 

unplanned work absences the day following colonoscopy (Newcomer, Shaw et al. 1999), and one 

examined the association of non-steroidal anti-inflammatory drugs (NSAIDs) and bleeding 

(Shiffman, Farrel et al. 1994). 

 

Process Measures 

 Sixteen of the 24 selected studies reported process measures related to colonoscopy. The 

most common process measures to report were sedation procedures (Godreau 1992; Waye, 

Lewis et al. 1992; Lugay, Otto et al. 1996; Pierzchajlo, Ackermann et al. 1997; Galandiuk and 

Ahmad 1998; Wexner, Forde et al. 1998; Newcomer, Shaw et al. 1999; Clarke, Jacobson et al. 

2001; Walker, McIntyre et al. 2003), reach-the-cecum rates (Godreau 1992; Rodney, Dabov et 

al. 1993a; Rodney, Dabov et al. 1993b; Hopper, Kyker et al. 1996; Pierzchajlo, Ackermann et al. 

1997; Galandiuk and Ahmad 1998; Rex, Imperiale et al. 1999; Nelson, McQuaid et al. 2002; 

Cotton, Connor et al. 2003), and procedure completion time (Rodney, Dabov et al. 1993a; 

Rodney, Dabov et al. 1993b; Galandiuk and Ahmad 1998; Wexner, Forde et al. 1998; 
24

Newcomer, Shaw et al. 1999; Nelson, McQuaid et al. 2002; Cotton, Connor et al. 2003). Three 

studies noted reasons for stopping the procedure (Godreau 1992; Rodney, Dabov et al. 1993a; 

Rodney, Dabov et al. 1993b), one reported average insertion depth (Rodney, Dabov et al. 1993a), 

one described the quality of bowel preparation (Nelson, McQuaid et al. 2002) and one described 

the method of bowel preparation (Godreau 1992). 

Sedation: The most common sedation procedures in the selected studies included the use 

of meperidine and diazepam (Godreau 1992; Waye, Lewis et al. 1992; Lugay, Otto et al. 1996; 

Pierzchajlo, Ackermann et al. 1997; Wexner, Forde et al. 1998). Three studies focused on 

midazolam alone (Galandiuk and Ahmad 1998; Newcomer, Shaw et al. 1999; Clarke, Jacobson 

et al. 2001) and one on meperidine and midazolam (Lugay, Otto et al. 1996). Fentanyl was 

described for use alone or in combination with other sedation procedures in two studies 

(Newcomer, Shaw et al. 1999; Clarke, Jacobson et al. 2001). Only one study described the use 

of propofol for sedation (Walker, McIntyre et al. 2003). 

Cecum reached: The cecum is the first portion of the large bowel joined to the small 

bowel; reaching the cecum indicates that the whole large bowel has been traversed during the 

colonoscopy. The majority of colonoscopy procedures successfully reach the cecum. The reachthe-cecum rate range was generally above 75% (Godreau 1992; Rodney, Dabov et al. 1993a; 

Hopper, Kyker et al. 1996; Pierzchajlo, Ackermann et al. 1997; Galandiuk and Ahmad 1998; 

Rex, Imperiale et al. 1999; Cotton, Connor et al. 2003); however, the rate was lower when 

sedation was not used (Rodney, Dabov et al. 1993a; Hopper, Kyker et al. 1996) or when there 

was poor bowel preparation (Pierzchajlo, Ackermann et al. 1997). In a study by Rodney and 

colleagues (Rodney, Dabov et al. 1993b), they reported a reach-the-cecum rate of 48% across all 

procedures, with a lower rate (38%) for those who had previous abdominal surgery and a higher 

rate (51%) for those who had no prior surgical history. It is not clear why the rate they report is 

so much lower than that reported in the other studies. 

Reasons for stopping procedure: The reasons given for stopping the colonoscopy 

procedure were obstruction (Godreau 1992; Rodney, Dabov et al. 1993a), inadequate preparation 

(Rodney, Dabov et al. 1993a; Rodney, Dabov et al. 1993b), inability to transervse the lumen (the 

interior of the colon) (Rodney, Dabov et al. 1993a; Rodney, Dabov et al. 1993b), severe 

diverticulosis (Godreau 1992), and pain (Rodney, Dabov et al. 1993a; Rodney, Dabov et al. 

1993b). Rodney and colleagues (Rodney, Dabov et al. 1993a) noted that the rate of stopping the 

procedure before it was completed ranged from 0% to 32%, with higher rates in patients who 

were not sedated. 

Procedure time: There was little variation in procedure time reported across studies 

(Rodney, Dabov et al. 1993a; Rodney, Dabov et al. 1993b; Galandiuk and Ahmad 1998; 

Wexner, Forde et al. 1998; Newcomer, Shaw et al. 1999; Nelson, McQuaid et al. 2002; Cotton, 

Connor et al. 2003). Procedure time average between 20 and 45 minutes but as noted in one 

study (Galandiuk and Ahmad 1998), the length of the procedure varied by whether the purpose 

of the colonoscopy was diagnostic, for biopsy, or for polypectomy. One study (Nelson, 

McQuaid et al. 2002) also reported the mean time to reach the cecum (10.5 minutes on average). 

Complications Related to Colonoscopy 

 All 24 studies reported outcomes from the colonoscopy procedure. In a subset of the 

selected studies, other procedures were studied concurrently including upper endoscopy (Lugay, 

Otto et al. 1996; Wexner, Forde et al. 1998), esophagogastroduodenoscopy (EGD) (Clarke, 
25

Jacobson et al. 2001; Bini, Firoozi et al. 2003; Walker, McIntyre et al. 2003), endoscopic 

retrograde cholangiopancreatography (ERCP) (Clarke, Jacobson et al. 2001; Bini, Firoozi et al. 

2003), barium enema (Godreau 1992; Timothy, Hicks et al. 2001), and flexible sigmoidoscopy 

(Anderson, Pasha et al. 2000; Gatto, Frucht et al. 2003). Unless otherwise noted, we only report 

findings specific to the colonoscopy procedure in this report. 

Perforation: The most serious complication of colonoscopy is perforation. Perforation 

can occur and be detected intra-operatively although there could be a delay in detection. Surgery 

is generally required to repair the perforation although in cases where the perforation is small 

and there is no peritonitis, more conservative treatment may be available. The risk of perforation 

is higher among patients who are over-sedated, had poor bowel preparation, or with acute 

bleeding. In the studies reviewed here, the perforation rate ranged from 0% to 0.8%. The 

highest rate of perforations reported occurred following polypectomy (Wexner, Forde et al. 

1998). Four studies identified delayed perforation rates of 0.02% within 7 days (Gatto, Frucht et 

al. 2003), 0.03% within four days (Korman, Overholt et al. 2003), 0.1% within 12 days (Waye, 

Lewis et al. 1992), and 0.8% within 3 months following polypectomy (Wexner, Forde et al. 

1998). 

Korman and colleagues (2003) examined the rate and location of perforation during 

colonoscopy in a network of endoscopic ambulatory surgery centers in the United States. The 

study followed patients up to four days and identified a 0.03% perforation rate for that specific 

Medicare population, with 62% of perforations occurring in the sigmoid colon, 16% in the 

cecum or ascending colon, 11% in the transverse colon, and another 11% in the rectum, 

descending colon and one unknown site. 

Two studies explored the association of patient characteristics with perforation (Korman, 

Overholt et al. 2003; Gatto, Frucht et al. 2003). In the study by Korman and colleagues (2003), 

the risk of perforation increased with increasing age of the patient, with the highest incidence of 

perforation occurring among those aged 70-79. Gatto and colleagues (2003) also identified 

advanced age as a strong predictor of perforation (p<0.001). Those with two or more 

comorbidities were also at increased risk of perforation with 6.26 per 1000 procedures as 

compared to 5.12 per 1000 for those with one co-morbidity and 1.69 per 1000 for those with no 

co-morbidities (p<0.001). Patients with the following indications for colonoscopy also had very 

high rates of perforation: diverticulosis (4.7 per 1000), hemorrhage (3.06 per 1000), 

inflammatory bowel disease (3.23 per 1000), and obstruction (7.59 per 1000). 

Bleeding: Bleeding following colonoscopy can occur immediately as is often the case 

following polypectomy but it is often delayed by several days. Immediate bleeding can be 

treated by cauterizing the source of the bleed. Delayed bleeding may resolve itself without 

further intervention however, in more serious cases, the patient may require transfusions, 

angiography, endoscopic therapy, or laparotomy in the most serious cases to resolve the 

bleeding. In the selected studies, bleeding was reported as an overall rate however, two studies 

reported the rate of bleeding for acute and late bleeding separately and two studies distinguished 

minor from major bleeding. Overall, the rate of bleeding following colonoscopy ranged from 

0.02% to 8.8%. Waye and colleagues (1992) reported a 0.5% rate of acute bleeding and a 0.7% 

rate of late bleeding (up to 12 days post-procedure. Rosen and colleagues (1993) reported 

slightly lower rates; 0.19% rate of acute bleeding and 0.23% rate of late bleeding (although 

timeframe is not reported). Nelson and colleagues (2002) reported a 0.22% rate of major GI 

bleeding requiring hospitalization and a 0.22% rate of minor bleeding as well. The highest rates 

of bleeding were reported by Shiffman et al. (1994). In this study, the authors report an 8.8% 
26

rate of minor bleeding among patients who used NSAIDs in the two weeks prior to the 

procedure. A lower rate of 2.5% was reported among those patients that had not used NSAIDs 

prior to the procedure. Major bleeding incidents were equivalent in both NSAID and nonNSAID users (0.9%). 

Other Complications: In addition to perforation and bleeding, other complications have 

been reported in the literature that may be rare but serious or very common and ranging in 

severity. Waye and colleagues report a 0.4% rate of postpolypectomy syndrome (where the 

colon is burned during polypectomy), which can be very serious (Waye, Lewis et al. 1992). Pain 

was commonly reported across studies (Rodney, Dabov et al. 1993a; Lugay, Otto et al. 1996; 

Newcomer, Shaw et al. 1999; Nelson, McQuaid et al. 2002; Bini, Firoozi et al. 2003; Walker, 

McIntyre et al. 2003), however it may be difficult to track this as an outcome in administrative 

data. Other conditions reported as complications of colonoscopy included: hypertension, 

hypotension, bradycardia, vasovagal events, weakness, dizziness, nausea, vomiting, shortness of 

breath, sore throat, headache, change in bowel habits, fatigue, chest pain, decreased appetite, 

fever, nocturia, genitourinary problems, rash, feeling sleepy, and bloating (Lugay, Otto et al. 

1996; Newcomer, Shaw et al. 1999; Zubarik, Fleischer et al. 1999; Nelson, McQuaid et al. 2002; 

Bini, Firoozi et al. 2003). These conditions too will be difficult to track in administrative data 

depending on their severity. It is possible however that more severe conditions may lead to a 

follow-up visit to a physician or an inpatient admission for treatment, and in these situations, we 

may be able to identify such complications in administrative data. 

Complications Unrelated to the Colon 

 Several studies identified in our review addressed complications unrelated to the 

colonoscopy procedure specifically, but addressed complications related to sedation. The most 

commonly reported complication related to sedation was oxygen desaturation with rates ranging 

from 0.9% to 25.7% (Poser and Ladik 1995; Lugay, Otto et al. 1996; Pierzchajlo, Ackermann et 

al. 1997; Galandiuk and Ahmad 1998; Rex, Imperiale et al. 1999; Nelson, McQuaid et al. 2002). 

Hypertension and hypotension were also commonly reported (Pierzchajlo, Ackermann et al. 

1997; Galandiuk and Ahmad 1998; Rex, Imperiale et al. 1999). Other cardiopulmonary 

conditions were reported in relation to sedation that were not well specified (Waye, Lewis et al. 

1992; Clarke, Jacobson et al. 2001). 

 Newcomer and colleagues (1999) examined the factors influencing work loss following 

colonoscopy. Older patients and females were more likely to have had an unplanned work 

absence following colonoscopy than others. Sedation and timing of the procedure did not 

influence work loss. 

 Many of the complications addressed in this review may lead to further health services 

utilization and colonoscopy has been identified as the proximal cause of death in rare cases. 

Hospitalization following colonoscopy was commonly reported across studies although the 

incidence of hospitalization is low (range: <0.01% - 1.8%) (Waye, Lewis et al. 1992; Rosen, Bub 

et al. 1993; Hopper, Kyker et al. 1996; Pierzchajlo, Ackermann et al. 1997; Galandiuk and 

Ahmad 1998; Wexner, Forde et al. 1998; Zubarik, Fleischer et al. 1999; Anderson, Pasha et al. 

2000; Nelson, McQuaid et al. 2002; Walker, McIntyre et al. 2003). Zubarik and colleagues 

(1999) also reported a 1.7% rate of emergency room or physician visit in the 30 days following 

colonoscopy. 
27

 Death was a rare occurrence following colonoscopy. Gatto and colleagues (2003) 

reported a rate of 51.9 deaths per 1000 perforations from the colonoscopy procedure. Anderson 

et al. (2000) reported an overall rate of mortality of 0.19 per 1000, which included both 

colonoscopy and flexible sigmoidoscopy. Nelson and colleagues (2002) reported one death out 

of 3,196 colonoscopies performed. 

Data Sources for Measuring Variation Across Settings 

 It will be possible to use the administrative data to measure differences in patient 

demographics and health status. It may be possible to measure certain characteristics that were 

reported as increasing the likelihood of perforation, e.g., diverticulosis and inflammatory bowel 

disease, and obstruction . For others, such as hemorrhage, it will be difficult to distinguish 

between a co-morbidity and a complication. 

Of the 24 selected for review, only one (Walker, McIntyre et al. 2003) did not state the 

data source for the process measures and complications reported. Most studies rely on the 

medical record and chart review to abstract the complications and process measures (Godreau 

1992; Waye, Lewis et al. 1992; Rosen, Bub et al. 1993; Rodney, Dabov et al. 1993b; Poser and 

Ladik 1995; Lugay, Otto et al. 1996; Pierzchajlo, Ackermann et al. 1997; Galandiuk and Ahmad 

1998; Wexner, Forde et al. 1998; Rex, Imperiale et al. 1999; Anderson, Pasha et al. 2000; 

Clarke, Jacobson et al. 2001; Timothy, Hicks et al. 2001; Nelson, McQuaid et al. 2002). A 

smaller number rely on operative logs or provider questionnaires (Rodney, Dabov et al. 1993a; 

Hopper, Kyker et al. 1996; Cotton, Connor et al. 2003; Korman, Overholt et al. 2003; Walker, 

McIntyre et al. 2003) or patient questionnaire (Shiffman, Farrel et al. 1994; Newcomer, Shaw et 

al. 1999; Zubarik, Fleischer et al. 1999; Bini, Firoozi et al. 2003) to gather information about 

process measures and complications of care. Only one study (Gatto, Frucht et al. 2003) used 

Medicare claims data to report complication rates associated with colonoscopy. The more 

serious complications are likely capable of being tracked in administrative data if they lead to an 

inpatient stay or in some cases, an emergency room or physician’s visit however, even the more 

serious complications such as bleeding and perforation may be treated intra-operatively or 

resolve on their own, never leading to follow-up care so administrative data will only capture the 

most serious of these complications. Other complications, such as the cardiopulmonary events, 

often stemming from the process of sedation may or may not be able to be tracked in 

administrative data. The likelihood of capturing these events will be increased if they lead to an 

inpatient stay. 

 With respect to procedure characteristics, the administrative data may be used to track 

sedation practices, i.e., whether sedation took place. However, claims data do not include 

enough detail to know what type of sedation was used. Other process measures such as the 

reach-the-cecum rate (a measure of the success of the procedure) and stopping the procedure 

(due to inadequate preparation, pain, or obstruction) cannot be observed in administrative data. 

29

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34
35 

APPENDIX A.1 

CATARACT SURGERY EVIDENCE TABLES 

Author and 

Date

Procedure, 

Provider 

Performing 

Procedure, Study 

Setting, & Study 

Design

Sample Size/ 

Description

Inclusion/ 

Exclusion Criteria

Study 

Follow-Up Measure

Method of 

Measure 

Assessment

Process Measures 

Topical ± oral sedativesTopical, IV sedatives: 3Topical, IV sedatives, oInjection ± oral sedativeInjection, IV sedatives: Injection, hypnotics: 33Injection, opioids, any sInjection, opioids, hypnInjection, any sedativesInjection, any sedativesminutes 

Katz, J. et al. (2001) 

Procedure: Extracapsular cataract extraction Provider: Ophthalmologist Setting: Inpatient, Ambulatory surgical center (academic and community-based) Design: Cohort 

N=19,156 (N=4,996 with topical anesthesia; N=14,163 with injection anesthesia) Sample description: Age – patients with topical anesthesia (range: 72.1-73.8 years); patients with injection anesthesia (range: 71.8 – 77.5 years); % Female (range: 54.7% to 66.6%); Patients covered by Medicare, private pay insurance, and the Canadian health system 

Exclusion: Patients aged < 50 years, history of myocardial infarction in last three months, surgeries under general anesthesia, surgeries on second eye within 28 days of first eye surgery, patients who could not provide informed consent, those who spoke a language other than Spanish or English 

7 days Mean duration 

of surgery by type of anesthesia 

Observational data 

Injection, any sedativesminutes 

Note: Sample Size/Sample Description cell includes descriptive information about the sample including (where available): basic demographics (age, gender, racharacteristics (Medicare, VA, etc.). 
36 

Complications Related to Cataract Surgery 

Intra-operative Posterior lens capsule tear with vitreous loss 

Medical record Inpatient: N=7 (2.3%) 

Outpatient: N=6 (2.0%) (N.S.) 

Wound dehiscence 

Medical record Inpatient: N=0 (0%) 

Outpatient: N=2 (0.67%(N.S.) 

Iris adherence to wound 

Medical record Inpatient: N=0 (0%) 

Outpatient: N=1 (0.33%(N.S.) 

Corneal edema Medical record Inpatient: N=6 (2.0%) 

Outpatient: N=5 (1.7%) (N.S.) 

Persistent iridocyclitis 

Medical record Inpatient: 1 (0.33%) 

Outpatient: N=5 (1.7%) (N.S.) 

Persistent ocular hypertension 

Medical record Inpatient: 2 (0.67%) 

Outpatient: 1 (0.33%) (N.S.) 

Clinically apparent cystoid macular edema 

Medical record Inpatient: 8 (2.7%) 

Outpatient: 1 (0.33%) (N.S.) 

Rhegmatogenous retinal detachment 

Medical record Inpatient: 3 (1.0%) 

Outpatient: 7 (2.3%) (N.S.) 

Holland, G.N. et al. (1992) 

Procedure: Phacoemulsification and extracapsular cataract extraction Provider: Ophthalmologist Setting: Inpatient, Hospital outpatient department (academic) Design: Cohort 

N=600 (N=300 inpatient; N=300 outpatient) Sample Description: Mean age: 71.5 +/- 11.3; 78.2% ≥ 65 years; 

62.8% female 

Exclusion: cases without 6 months follow-up data; intracapsular extraction procedure; patients who underwent cataract surgery in combination with other ocular surgical procedures 

12 months 

Opacified posterior lens capsule 

Medical record Inpatient: 15 (5.0%) 

Outpatient: 17 (5.7%) (N.S.) 
37 

Capsulotomy of presumed pseudophakia (per personyear) 

Administrative data 

10% to 24% by state 

Retinal detachment 

Administrative data 

N=337 patients 1.6% with capsulotomy(p<0.02) Younger age, white raceperformance of capsulo

Javitt, J.C. et al. (1992) 

Procedure: Extracapsular cataract extraction Provider: Not specified Setting: Inpatient, Hospital outpatient department, Ambulatory surgical center, Physician’s office Design: Population-based cross-section 

N=57,103 Sample Description: Medicare population; 100% ≥ 65 

years; 65.8% female; 8.3% minority; 14.5% with diabetes 

Inclusion: Enrolled in both Medicare Part A&B Exclusion: enrolled in HMO, residing outside the U.S., < 65 years, underwent intracapsular cataract extraction, type of extraction not specified, those for whom cataract surgery was combined with corneal, retinal, or glaucoma procedures 

36 months 

Retinal break Administrative 

data 

N=194 (RR=1.94; 1.21, 3.12 usretinal break) (RR=2.49; 1.68, 3.69 usretinal break) 
38 

3-year cumulative probability of retinal detachment (inpatient only) 

Administrative data 

0.56% (0.44%-0.68%) i0.72% (0.68%-0.76%) i(p=0.01) 

3-year cumulative probability of retinal detachment (including inpatient and outpatient) 

Administrative data 

0.81% (0.67%-0.94%) i(1986-1987) 0.72% (0.68%-0.76%) i(p=0.23) 

1-month cumulative probability of hospitalization for endophthalmitis 

Administrative data 

0.055% (0.036%-0.074%(1986-1987) 0.085% (0.075%-0.095%(1984) (p=0.01) 

Javitt, J.C. et al. (1994) 

Procedure: Phacoemulsification and extracapsular cataract extraction Provider: Not specified Setting: Inpatient, Hospital outpatient department, Ambulatory surgical center, Physician’s office Design: Population-based cross-section 

N=57,103 (inpatient & outpatient – 1986-1987) N=330,000 (inpatient only - 1984) Sample Description: 

Medicare population; 100% > 65 years; 66% Female; 7% minority 

Inclusion: ≥ 66 years of age Exclusion:Enrolled in an HMO, not enrolled in both Medicare Part A & B 

36 months 

1-year cumulative probability of hospitalization for endophthalmitis 

Administrative data 

0.081% (0.057%-0.10%(1986-1987) 0.12% (0.10%-01.13%) (p=0.01) 
39 

Shammas, H.J. (1996) 

Procedure: Extracapsular cataract extraction or phacoemulsification with intraocular lens implantation and trabeculectomy Provider: Ophthalmologist Setting: Ambulatory surgical center Design: Cohort 

N=150 (N=96 extracapsular cataract extraction; N=54 phacoemulsification) No sample description available 

Inclusion: Patients with open-angle glaucoma 

6 months Lens dislocation Medical record N=18 (18.7%) with extr

N=2 (3.7%) with phaco(p<0.01) 
40 

Interoperative pain 

Patient questionnaire 

Peribulbar: 4% mild paiSub-Tenon’s: 1% mild p

Pain on first day post-surgery 

Patient questionnaire 

Peribulbar: 11% mild pasevere pain Sub-Tenon’s: 9% mild psevere pain 

Kollarits, C.R. et al. (1998) 

Procedure: Phacoemulsification Provider: Ophthalmologist Setting: Ambulatory surgical center Design: Case series 

N=200 (N=100 with peribulbar anesthesia; N=100 with subtenon’s anesthesia) No sample description available 

Inclusion: not sedated 

1 day 

Ocular motility immediately following surgery 

Provider questionnaire 

Peribulbar: 82% none, 1Sub-Tenon’s: 80% nonenormal 
41 

Vitreous loss with posterior capsule rupture or zonular dehiscence 

Medical record Total: N=7 (1.8%) 

Early: N=5 (2.5%) Late: N=2 (1.0%) 

Posterior capsule rupture 

Medical record Total: N=3 (0.8%) 

Early: N=2 (1.0%) Late: N=1 (0.5%) 

Zonular dehiscence 

Medical record Total: N=2 (0.5%) 

Early: N=0 (0.0%) Late: N=2 (1.0%) 

Iris trauma Medical record Total: N=2 (0.5%) 

Early: N=0 (0.0%) Late: N=2 (1.0%) 

Intraoperative wound leak requiring sutures 

Medical record Total: N=6 (1.5%) 

Early: N=2 (1.0%) Late: N=4 (2.0%) 

Total intraoperative complications 

Medical record Total: N=20 (5.1%) 

Early: N=9 (4.6%) Late: N=11 (5.5%) 

1-day postoperative complications (based on N=387) 

Medical record Total: N=9 (2.3%) 

Early: 6 (3.1%) Late: 3 (1.5%) 

Corneal wound leak (1-day postoperative) 

Medical record Total: N=3 (0.8%) 

Early: N=3 (1.6%) Late: N=0 (0.0%) 

Retained cortex in visual axis (1-day postoperative) 

Medical record Total: N=2 (0.5%) 

Early: N=1 (0.5%) Late: N=1 (0.5%) 

Vitreous around loose zonules (1-day postoperative) 

Medical record Total: N=1 (0.3%) 

Early: N=1 (0.5%) Late: N=0 (0.0%) 

Corey, R.P. et al. (1998) 

Procedure: Phacoemulsification with intraocular lens implantation Provider: Ophthalmologist Setting: Hospital outpatient department (Urban/rural Veteran’s Administration) Design: Case series 

N=396 (N=197 with early experience with surgery; N=199 with more experience with surgery) No sample description available 

Exclusion:Patients with traumatic cataracts, subluxated lenses, pre-existing zonular dehiscence, corneal scarring, or those having combined procedures 

1 day 

Nuclear fragment in the angle (1-day post-operative) 

Medical record Total: N=1 (0.3%) 

Early: N=1 (0.5%) Late: N=0 (0.0%) 
42 

Bohigian, G.M. (1999) 

Procedure: Phacoemulsification and extracapsular cataract extraction Provider: Ophthalmologist Setting: Ambulatory surgical center Design: Case series 

N=19,269 No sample description available 

Not specified 15 days Incidence of 

culture-positive endophthalmitis 

Provider questionnaire 

N=9 (0.05%) 1:2,141 surgeries N=4 (0.08%) without poN=5 (0.03%) with povid

Intraoperative pain 

Patient questionnaire 

Tetracine: 4 (8%) mild pLidocaine: 3 (6%) mild 

Harman, D.M. (2000) 

Procedure: Clear corneal cataract surgery w/foldable intraocular lens implantation Provider: Ophthalmologist Setting: Ambulatory surgical center Design: Cohort 

N=200 (N=50 with tetracaine anesthesia; N=50 with lidocaine 2% jelly anesthesia; N=50 with 1mg sublingual lorazepam; N=50 with no sedation) Co-morbid Conditions: hypertension 

Not specified 0 days 

Intraoperative pressure 

Patient questionnaire 

Tetracine: 5 (10%) mild Lidocaine: 8 (16%) mild 
43 

Golnik, K.C. et al. (2000) 

Procedure: Phacoemulsification Provider: Ophthalmologist Setting: Ambulatory surgical center (urban, community-based) Design: Case series 

N=118 Sample Description: Mean age: 71; 60.2% female 

Not specified 30 days Incidence of 

ocular misalignment 

Medical record At 1 day: 22% (n=22 of 

At 7 days: 10% (n=9 of At 30 days: 7% (n=6 of 

Posterior capsule rupture 

Provider Questionnaire 

N=1 with vitreous loss iN=1 without vitreous lo(NS) 

Chemosis Provider 

questionnaire 

N=15 (75%) in retrobulN=1 (5%) in topical gro(p<0.001) 

Eyelid hematoma 

Provider questionnaire 

N=10 (50%) in retrobulN=0 (0%) in topical gro(p<0.001) 

Subconjunctival hemorrhage 

Provider questionnaire 

N=5 (25%) in retrobulbN=0 (0%) in topical gro(p=0.04) 

Mean postoperative pain (0-10 scale) 

Patient questionnaire 

0.15 in retrobulbar grou0.35 in topical group; (p=.23) 

Mean perioperative pain (0-10 scale) 

Patient questionnaire 

0.15 in retrobulbar grou0.25 in topical group; (p=0.41) 

Ahmed, I.I. et al. (2002) 

Procedure: Phacotrabeculectomy Provider: Ophthalmologist Setting: Ambulatory surgical center (academic) Design: Randomized controlled trial 

N=40; N=20 (retrobulbar anesthesia); N=20 (topical anesthesia) No sample description provided 

Inclusion: visually 

significant cataract and uncontrolled glaucoma; Exclusion: communication difficulties, monocular status, taking anticoagulant medications 

0 days 

Mean pain during anesthesia delivery (0-10 scale) 

Patient questionnaire 

0.10 in retrobulbar grou0.45 in topical group; (p=0.08) 

Note: Sample Size/Sample Description cell includes descriptive information about the sample including (where available): basic demographics (age, gender, racharacteristics (Medicare, VA, etc.). 
44 

Complications Unrelated to the Eye: Anesthesia Complications Mayer A.S. (1993) 

Procedure: Extracapsular cataract extraction Provider: Ophthalmologist Setting: Ambulatory surgical center Design: Case report 

N=1 Sample Description: Age: 72, Female 

Not specified 2 days Adverse events 

from local anesthesia (retrobulbar anesthetic injection) 

Medical record Respiratory arrest; high 

without effusion or infilatrioventricular block at fascicular block; second 

Frequency of nausea 

Patient questionnaire 

Placebo: 27.4% Metoclopramide: 11.8% Ondansetron: 2.6% P vs. M: p=0.0001 P vs. O: p=0.0001 M vs. O: p=0.04 

Ascaso, F.J. et al. (1997) 

Procedure: Extracapsular cataract extraction Provider: Ophthalmologist Setting: Ambulatory surgical center Design: Randomized controlled trial 

N=251 (N=84 placebo (P); N=51 Metoclopramide (M); N=116 Ondansetron (O)) Sample Description: Mean age: P=70+/-9; M=68+/-10; O=68 +/-14; % Female: P=53.6%; M=45.1%; O=46.6% 

Exclusion:Patients predisposed to nausea and vomiting secondary to gastrointestinal reflux, gastroparesis, motion sickness, inner ear disorder, CNS disorder, use of anti-emetics in 24 hour period prior to surgery, use of intragastric tubes after operation 

1 day 

Frequency of vomiting 

Patient questionnaire 

Placebo: 21.4% Metoclopramide: 5.9% Ondansetron: 0.9% P vs. M: p=0.0001 P vs. O: p=0.0001 M vs. O: N.S. 
45 

Rosenfeld, S.I. et al. (1999) 

Procedure: Phacoemulsification and extracapsular cataract extraction Provider: Ophthalmologist Setting: Ambulatory surgical center Design: Case series 

N=1006 Mean age: 76.1 Co-morbid Conditions: Renal disease, diabetes, hypertension, cancer, vascular disease, heart disease, pulmonary disease, collagen vascular disease, thyroid disease 

Exclusion: Patients undergoing combination procedures 

0 days Intervention by 

anesthesia personnel required (peribulbar anesthesia) 

Provider questionnaire 

N=548 episodes of interN=376 (37.4%) total paN=205 (20.4%) before sN=220 (21.9%) intraopeN=27 (2.7%) after surgeIncreased risk of intervehypertension (p=0.03); prenal disease (p=0.02); pdiagnosis (p=0.001) 

Sedation effect on blood pressure in hypertension patients 

Medical record Decrease in systolic pre

sedation (0%) Decrease in diastolic prsedation (3.0%) Increase in systolic: Lor(1.5%) 

Harman, D.M. (2000) 

Procedure: Clear corneal cataract surgery w/foldable intraocular lens implantation Provider: Ophthalmologist Setting: Ambulatory surgical center Design: Cohort 

N=200 (N=50 with tetracaine anesthesia; N=50 with lidocaine 2% jelly anesthesia; N=50 with 1mg sublingual lorazepam; N=50 with no sedation) Co-morbid Conditions: Hypertension 

Not specified 0 days 

Sedation effect on blood pressure in nonhypertension patients 

Medical record Decrease in systolic pre

sedation (3.4%) Decrease in diastolic prsedation (3.5%) 

Note: Sample Size/Sample Description cell includes descriptive information about the sample including (where available): basic demographics (age, gender, racharacteristics (Medicare, VA, etc.).
46 

Complications Unrelated to the Eye: Medical Complications, Hospitalization, Death 

Cardiovascular events (MI, ischemia, congestive heart failure, arrhythmias, hypertension, hypotension) 

Observational data 

Intraoperative: N=506 Postoperative: N=111 (

Cerebrovascular events 

Observational data 

Intraoperative: N=0 (0.Postoperative: N=7 (0.0

Pulmonary events 

Observational data 

Intraoperative: N=15 (0Postoperative: N=9 (0.0

Upper respiratory events 

Observational data 

Intraoperative: N=1 (0.Postoperative: N=33 (0

Hospitalizations Observational 

data 

Intraoperative: N=8 (0.Postoperative: N=58 (0

Death Observational 

data 

Intraoperative: N=0 (0.Postoperative: N=7 (0.0Topical 

± oral sedatives

Topical, IV sedatives: NTopical, IV sedatives, oInjection 

± oral sedative

Injection, IV sedatives: Injection, hypnotics: NInjection, opioids, any sInjection, opioids, hypnInjection, any sedativesInjection, any sedatives(2.32%) 

Intraoperative medical events by type of anesthesia 

Observational data 

Injection, any sedatives(4.04%) Topical 

± oral sedatives

Topical, IV sedatives: NTopical, IV sedatives, oInjection 

± oral sedative

Injection, IV sedatives: Injection, hypnotics: NInjection, opioids, any sInjection, opioids, hypn

Katz, J. et al. (2001) 

Procedure: Extracapsular cataract extraction Provider: Ophthalmologist Setting: Inpatient, Ambulatory surgical center (academic and community-based) Design: Cohort 

N=19,156 (N=4,996 with topical anesthesia; N=14,163 with injection anesthesia) Sample Description: Age – patients with topical anesthesia (range: 72.1-73.8 years); patients with injection anesthesia (range: 71.8 – 77.5 years); % Female (range: 54.7% to 66.6%); Patients covered by Medicare, private pay insurance, and the Canadian health system 

Exclusion: Patients aged < 50 years, history of myocardial infarction in last three months, surgeries under general anesthesia, surgeries on second eye within 28 days of first eye surgery, patients who could not provide informed consent, those who spoke a language other than Spanish or English 

7 days 

Intraoperative and postoperative hospitalizations and deaths by type of anesthesia 

Observational data 

Injection, any sedatives
47 

Injection, any sedatives(0.07%) Injection, any sedatives(0.43%) 

Note: Sample Size/Sample Description cell includes descriptive information about the sample including (where available): basic demographics (age, gender, racharacteristics (Medicare, VA, etc.). 
48 
49

APPENDIX A.2 

CRANIAL AND SPINAL MAGNETIC RESONANCE (MR) IMAGING EVIDENCE TAB

Author and 

Date

Procedure, 

Provider 

Performing 

Procedure, Study 

Setting, & Study 

Design

Sample Size/ 

Description

Inclusion/ 

Exclusion Criteria

Study 

Follow-Up Measure

Method of 

Measure 

Assessment

Structural Measures 

N=26 of 53 RespondentN=3 of 53 Noncontrast with history of reaction N=15 of 53 Noncontrashistory of moderate to sN=4 of 53 Noncontrast history of severe reactio

Precautions in place at institution for patients with history of reactions to iodinated contrast material 

Provider questionnaire 

N=3 of 53 Premedicate N= 5 of 53 Did not admN=19 of 53 No policy oN=3 of 53 Premedicate hour prior to scan N=26 of 53 PremedicatN=15 of 53 Premedicatantihistamines 

Precautions in place at institution for patients with history of reaction to gadoliniumbased contrast agents 

Provider questionnaire 

N=6 of 53 Premedicate antihistamines 

Observed by ACLS-certified healthcare worker 

Provider questionnaire 

N= 23 of 53 Responden

Observed by BLS-certified healthcare worker 

Provider questionnaire 

N=21 of 53 Respondent

Murphy K.P. et al. (1999) 

Procedure: MRI with gadoliniumbased contrast (Magnevist, Prohance, Omniscan) Setting: Includes freestanding clinics (academic) Design:Population-based cross-sectional 

N=53 American Society of Neuroradiology program directors representing 105 centers and 835,535 doses of MR contrast No sample description available 

Inclusion:Director of fellowship program of “American Society of Neuroradiology in the United States and Canada” 

Not specified 

Arrangements in place with code team to manage emergency 

Provider questionnaire 

N=10 of 24 Freestandinplace N=14 of 24 (58%) No a

Note: Sample Size/Sample Description cell includes descriptive information about the sample including (where available): basic demographics (age, gender, racharacteristics (Medicare, VA, etc.). 
50 

Complications Related to MRI of the Brain 

N=29 (7.1%) Total numevent. N=41 Total number of aconsidered possibly or p20/41 considered unrelamouth, nausea, stiff necclinically insignificant) N= 14 out of 27 Numbewith adverse events Listed below: adverse rassociated with gadoterN=6 of 21 reactions (1.4N=5 of 21 reactions (1.2N=2 of 21 reactions (0.5N=2 of 21 reactions (0.5N=2 of 21 reactions (0.5N=1 of 21 reactions (0.2N=1 of 21 reactions (0.2N=1 of 21 reactions (0.2N=1 of 21 reactions (0.2

Adverse symptoms or signs 

Patient verbally asked about possible ill effects (no standard questionnaire) 

Listed below: number aN=7 (1.7%) Nausea N=7 (1.7%) Dysgeusia N=6 (1.5%) Headache N=3 (0.7%) Dry mouth N=2 (0.5%) Pain at injeN=2 (0.5%) Rash N=1 (0.2%) each for the dyspnea, facial edema, t

neck, chest pain, paresthrash, rhinitis, tinnitus, uNo significant relationsrate of injection 

Runge, V.M. et al. (1991) 

Procedure: MRI with gadoteridol Setting: Not 

specified Design: Controlled before and after 

N=411 Sample Description: Mean age: 49 +/- 16 years; 47% Female 

Inclusion: Suspected intracranial or spine disease Exclusion: pregnancy, lactating; history of clinically significant hemolytic anemia 

1 day for safety eval.; 8 weeks for efficacy portion 

Change in physical exam 

Not specified N=26 patients had chan

improved; none were cocontrast administration; 
51 

Change in vital signs 

Not specified N=0 Remarkable chang

If 10% change in vital sN=113 Decrease heart rN=135 Increase heart raN=81 Decrease systolic N=82 Increase systolic N=105 Decrease diastolN=114 Increase diastoliIf 20% change in vital sN=75 Decrease respiratN=90 Increase respiratoN=26 Decrease temperaN=11 Increase temperatN=1 Patient (possibly aadministration) Change N=30 Patients (6 cases contrast) Change in seruN=1 Patient (possibly ain urine protein N=0 patients Change in 

Change in lab values 

Not specified 

N=0 patients with creatwith change in creatinincreatinine N=2 (2.3%) Overall numany adverse event N=1 Metallic taste (milwithout treatment) 

Adverse Symptoms/Signs 

Not specified 

N=1 Headache (mild, shtreatment) 

Carvlin, M.J. et al. (1992) 

Procedure: MRI with gadoteridol At 0.5, 0.1, 0.2, or 0.3 Setting: Not 

specified (Multicentered, academic) Design:Controlled before and after 

N=86 patients Sample Description: Mean age: 51 +/- 17 years 

Inclusion:Diagnosis of intracranial tumor Exclusion: Not specified 

2 Days 

Change in vital signs 

Not specified N=0 
52 

N=0 Site Pain N=0 Burning N=0 Erythema N=0 Headache N=0 Dizziness N=0 Taste perturbation 

Adverse symptoms or signs 

Not specified 

Change in physical exam 

Not specified N=0 

Change in vital signs 

Not specified N=0 

N=9 Overall number of N=1 Increase in white bN=5 Increase in polymoN=4 Increase in band ceN=1 Increase in monocyN=2 Decrease in eosinoN=1 Decrease in lymphN=1 Decrease in monoc*Above observations occorticosteroids N=2 Increase in glucose received corticosteroidsN=1 Decrease in total pN=1 Decrease in hemog

Yuh, W. et al. (1992) 

Procedure: MRI with gadoteridol -initial injection 0.1 mmol/kg -after 30 minutes, additional dose 0.2 mmol/kg Setting: Not 

specified Design: Controlled Before/After 

N=31 patients Sample Description: Age range: 43 to 76 years; 13/27 Female (Description of sample provided for efficacy portion of study, which excluded 4 patients) 

Inclusion:Clinical suspicion of brain metastases or metastases on brain angiography, CT, or MRI 

1 day 

Change in lab values 

Not specified 

N=14 Decrease in iron lattributed to massive heattributed to extensive p
53 

N=46 of 439 (10%) Totexperienced adverse symN=66 Total number of aAge, sex, injection voluof adverse event None deemed “definitelN=15 Headache N=8 Dizziness N=7 (1 case deemed “pNausea N=4 (1 case deemed “pTaste perversion N=3 (3 cases deemed “pUrticaria N=3 (1 case deemed “pVasodilation N=3 (1 case deemed “pInjection site reaction N=2 Anxiety N=2 Convulsion N=2 Abnormal coordinN=2 Chest pain N=2 Paresthesia N=2 Tinnitus 

Adverse symptoms or signs 

Patient questionnaire and provider questionnaire 

N=11 Other (1 case deedrug; 1 patient died 2 dagadodiamide, with death condition including degdehydration, cachexia, nhematologic and renal p

measurements obtained after procedure) 

Sze, G. et al. (1993) 

Procedure: MRI with gadodiamide (Omniscan) Setting: Not 

specified Design: Controlled before and after 

N=439 (351 brain, 88 spine) Sample Description: Mean age: 49 +/- 16 years Gender: “Equal balance of men and women” 

Inclusion: Known or suspected CNS lesions Exclusion: <18 years; unconscious patients or those judged uncooperative; history of anaphylaxis or hemolytic anemia; pregnant; lactating; women of childbearing potential for whom risk was greater than benefit; clinically significant renal or hepatobiliary disease; patients highly suspected for alcohol or drug abuse; history of seizures uncontrolled by medication; serious concurrent illness; emergency patients; patients entered into investigational drug trial within the prior 7 days; patients who had received contrast media within the prior 3 days; patients in whom MRI was contraindicated. 

36 hours 

Change in vital signs 

Not specified No clinically significan
54 

Change in neurological exam 

Not specified No changes 

No trends in blood labotoxicity in any organ syN=17 Iron Increase from the span of reference raN=16 Iron Decrease frothe span of reference raN=9 Direct bilirubin Inc100% of the span of refN=6 Direct bilirubin Dethan 100% the span of rN=3 ALT (SGPT) Incre100% of the span of refN=6 ALT (SGPT) Decr100% the span of refereN=5 AST (SGOT) Incre100% of the span of refN=5 AST (SGOT)Decr100% the span of refereN=2 GGT Increase from the span of reference raN=1 GGT Decrease frospan of reference range N=1 Platelet count Incr100% of the span of refN=2 Platelet count Decr100% the span of refereN=0 Total bilirubin Incr100% of the span of refN=2 Total bilirubin Dec100% the span of refereN=0 Urea nitrogen Incr100% of the span of refN=2 Urea nitrogen Dec100% the span of refere

Change in lab values 

Not specified 

N=0 Creatinine Increase 100% of the span of refN=1 Creatinine Decreas100% the span of refere
55 

 N=0 Alkaline phosphata

greater than 100% of thN=1 Alkaline phosphata

greater than 100% the s

N=8 out of 133 (6%) Pasymptoms or signs N=3 (2.3%) Patients wiN=2 (1.5%) Patients wiN=1 (0.8%) Patients wiN=1 (0.8%) Patients wi

Adverse symptoms or signs 

Not specified 

N=1 (0.8%) Patients wi

Clinically significant change in vital signs 

Not specified N=0 

Zoarski, G.H. et al. (1993) 

Procedure: MRI with gadoteridol Setting: Not 

specified; Multicentered—12 participating institutions Design: Controlled before and after 

N=140 Enrolled, but 1 MRI malfunction and 6 patients had claustrophia or clinical condition preventing completion of study Sample Description: Mean age: 53 +/- 15 years; 59/133 Female 

Inclusion:Suspected extracranial and or extraspinal head and neck pathology Exclusion: <18 years, pregnant, lactating, history of hemolytic anemia, known sensitivity to MR contrast material 

56 days (1 day for adverse events, 8 weeks for follow up of postcontrast MR diagnosis) 

Change in overall lab values 

Not specified N=19 patients with abn

N=41 Abnormal lab valN=2 of 133 (1.5%) Patrelated to gadoteridol (iserum iron). All lab chapatient with low iron latdeficiency anemia 
56 

N=4 of 67 patients (totaN=6 adverse events (totN=2 of 4 adverse eventcontrast (dizziness and lpatient with left parietal mental status in patient 

Adverse symptoms or signs 

Not specified 

N=2 of 4 adverse events contrast (nausea, hypotetwo hours post-contrast

Change in physical exam 

Not specified No difference at 24 hou

recovering after surgery examination 

Yuh, W.T.C. et al. (1994) 

Procedure: MRI with gadoteridol at 0.3 mmol/kg cumulative dose Setting: Not 

specified Design: Controlled before and after 

N=68 patients; 67 patients included in safety analysis Sample Description: Mean age: 57 +/- 11 years; 30/67 Female 

Inclusion:Radiological evidence or clinical suspicion of brain metastases Exclusion: Less than 18 years or greater than 76 years, pregnant, lactating, patients who had undergone contrast-enhanced MR procedures within the previous 48 hours, patients with histories of sensitivity to MR contrast media, and patients with pacemaker implants, aneurysm clips, any other condition that precludes proximity to strong magnetic field, severe claustrophobia 

1 day 

Change in lab values (chemistry, hematology, urinalysis) 

Not specified No clinically significant 

changes considered to badministration 
57 

N=372 (2.4%) Patients reactions. N=167 (44.9%) Patients 1 hour after injection N=0 Patients with seriocontrast (N=2 serious reunrelated to drug. One of severe vertigo in patipositional vertigo) No statistically significaof different races Occurrence of adverse rhistory N=31 out of 831 (3.7%) and history of asthma. (bronchospasm) vs. N=312 out of 13,219 (2reaction and no history N=29 out of 1,446 (2.0%and asthma history unkn

Nelson, K.L. et al. (1995) 

Procedure: MRI with gadopentetate dimeglumine (Magnevist) -0.1 mmol/kg Setting: Not specified; Multicentered--207 MR imaging sites Design: Controlled before and after 

N=15496 patients; N=4,278 (27.6%) followed to 24 hours after procedure Sample Description: Mean Age: 48.3 years (969 patients <18 years): 8168 (53%) Female; 2765 (18%) Non-White Comorbid conditions: Included asthma, allergies 

Inclusion: 80 consecutive patients at each site who received gadopentetate dimeglumine before MR examination. “Patients whose characteristics conformed to those listed on the package insert for MR imaging of the brain and spine.” 

1 day Adverse 

reaction (any unfavorable or unintended alteration in the clinical status of the patient that was temporally associated with the use of gadopentetate dimeglumine, even if it was not considered to be related to administration of the drug) 

Case Report Form, Patient questionnaire 

N=144 out of 3860 (3.7reaction and history of aN=16 out of 75 (21.3%) and history of reaction tN=54 out of 857 (6.3%) and history of reaction t
58 

Occurrence of adverse rduration N=134 out of 4,606 (2.9reaction and injection dN=237 out of 10,848 (2reactions and injection d(p>.05) Paresthesia occurred at (0.3%) than slower (0.1vomiting, injection site statistically significant (duration groups. N=71 Nausea N=68 Headache N=29 Dizziness N=28 Injection site reacN=26 Paresthesia N=23 Nausea/vomiting N=21 Pain N=19 Asthenia N=14 Rash N=11 Vasodilation N=11 Urticaria N=51 Other adverse reapatients 
59 

N=118 out of 1709 patisymptoms or signs. N=174 Total number of N=79 (4.6%) Patients econsidered possibly, procontrast N=2 Severe adverse eveconsidered unrelated to possibly related to contrN=24 out of 1709 (1.4%drug-related N=22 out of 1709 (1.3%considered drug-related N=13 (0.8%) Headacherelated N=9 (0.5%) Vasodilatatrelated N=8 (0.5%) Hypotensiorelated N=8 (0.5%) Pain; 6 (0.4N=7 (0.4%) Injection sidrug-related N=7 (0.4%) Urticaria; 7 N=6 (0.4%) Dizziness; N=6 (0.4%) Vomiting; N=5 (0.3%) Rash; 3 (0.N=4 (0.2%) Paresthesiarelated N=4 (0.2%) Tachycardirelated N=3 (0.2%) ConvulsionN=3 (0.2%) Dry mouthrelated N=2 (0.1%) AmblyopiaN=2 (0.1%) Asthenia; 0 N=2 (0.1%) Confusion; N=2 (0.1%) Dyspnea; 0 N=2 (0.1%)Edema; 0 coN=2 (0.1%) Gingivitis; N=2 (0.1%) Incoordinat

Olukotun. A.Y. et al. (1995) 

Procedure: MRI with gadoteridol Setting: Not specified Design: Case Series/Controlled before and after (2 phase I, 1 phase II, 13 phase III or IIIb) 

N=1709 total enrolled (1596 participated) Sample Description: 779/1709 Female; 10/28 Female for phase I study 

Inclusion: Suspected or confirmed disease for which MRI study was indicated Exclusion: “inability to meet inclusion criteria, a previous contrastenhanced MRI evaluation within 48 hours before administration of gadoteridol injection, a known history of hemolytic anemia or other hemoglobinopathy, known sensitivity to paramagnetic contrast agents, presence of a pacemaker, aneurysm clip, or any other ferrous object that might preclude proximity to a strong magnetic field, pregnancy, lactation 

Not specified 

Adverse event Not specified 

N=2 (0.1%) Lacrimatiodrug-related 
60 

N=2 (0.1%) Syncope; 1 N=1 (<0.1%) for each oAgitation, anorexia, bracough increased, death, 

fever, hiccup, hypertens

myasthenia, “neck,” paleffusion, tinnitus, vasos

Change in lab values 

Not specified For Phase I: N=6 patien

excretion For Phase II-III: N=49 of 1,681 (2.9%) PN=27 of 1,681 Patients N=5 of 1,681 Patients wN=1 of 1,681 Patients wphosphorus, and urinary Paired pre- and post-contotal bilirubin (N=1,557pre- and post-contrast v

Change in vital signs 

Not specified For Phase I: N=1 of 28 

(considered unrelated to diagnosed as previously 

atrioventricular block) For Phase II-III: N=1 of resolved within 2 hours 

Significant electrocardiogram changes 

Not specified N=0 
61 

Not specified N=233 Adverse events 

2656 total exposures, ovone adverse events (% oIncidence of having at l(by age group) >60 y.o. ( 4.4%) vs. 18-60 y.o. (7.9%) vs. <18 y.o. (3.4%) * not sttowards lower incidence (by gender) Male (5.8%) vs. Female (7.4%) 

Not specified Adverse events by body 

resulting in at least one Digestive: 59 (2.2%) Body: 46 (1.7%) Special senses: 30 (1.1%Cardiovascular: 27 (1.0Cutaneous: 22 (0.8%) Nervous: 21 (0.8%) Respiratory: 10 (0.4%) 

Not specified Nausea (1.5%), similar Not specified Taste perversion (0.9%) Not specified Headache (0.6%), similNot specified N=1 Vasospasm 

Adverse symptoms or signs 

Not specified N=2 Death, considered 

Change in physical exam 

Not specified “Low incidence of clini

Change in vital signs 

Not specified “Low incidence of clini

Runge, V.M. and Parker, J.R. (1997) 

Procedure: MRI with gadoteridol --0.1 mmol/kg --0.2 mmol/kg --0.3 mmol/kg Setting: Not 

specified Design: Case Series/Controlled before and after 

N=2,481 Patients (Combined for phase I-IIIb clinical trials; 1909 from US, 747 from Europe) N=2,656 Injections of gadoteridol (exposures) Sample Description: Mean age: 49 years; 747 patients >60 years old; 1314/2481 Female 

Not Specified Not 

Specified 

Change in lab values 

Not specified No consistent elevation 

total bilirubin 
62 

Overall adverse event N=13 (11.6%) patients N=15 adverse events N=28 (24.1%) patients N=40 adverse events N=24 (22.2%) patients N=32 events “Most commonly reporperversion and headachN=1 Patient Serious nauhospitalization (investigcontrast, however) 

Adverse symptoms or signs 

Not specified 

“The majority of patienperception of heat, coldadministration of OptiM

Changes in vital signs 

Not specified “Comparisons of pre- an

for pairs of doses within statistically significant (to suggest systematic chN=7 (6.3%) Patients in decreased blood pressurN=5 (4.3%) Patients in increased heart rate N=5 (4.3%) Patients in decreased heart rate N=3 (2.8%) Patients in decreased blood pressurN=3 (2.8%) Patients in decreased heart rate 

Grossman , R.I. et al. (1998) 

Procedure: MRI with OptiMark (0.1 + 0.3; 0.1 + 0.5; or 0.3 +0.5) with doses administered within 7-day period, but with minimum of 24 hours between doses. Setting: Not specified; (Multicenter, including U.S. as well as Canada, Germany) Study Design:Controlled before and after 

N=172 patients Sample Description: Mean age: 46.1 years; 49% Female; 8% non-White 

Inclusion: Known or suspected pathology and or structural abnormality of the brain or spine. Exclusion: Contraindication to MRI, renal impairment—serum creatinine >1.5 mg/dL, anemia, hemoglobinopathies, noncontrast or contrast-enhanced MR or CT scan within 24 hours of the study entry 

Not specified 

Changes in laboratory values 

Not specified N=0 Clinically significa

alkaline phosphatase ansignificant) 
63 

Non-allergic reaction (nN=314 (0.046%) For GN=171 (0.267%) For GN=11 (0.015%) For GadNon-allergic reaction crN= 9 No precautions foN=36 No precautions foN=0 Noncontrast MRI oN=8 Noncontrast MRI aadministration N=3 Administer a differN=3 Administer a nonioN=0 Premedication Mild reaction resemblinerythema, skin irritationN=107 (0.016%) For GN=49 (0.077%) For GadN=12 (0.016%) For GadMild reaction cross-tabuN=9 No precautions for N=20 No precautions foN=5 Noncontrast MRI oN=13 Noncontrast MRI administration N=5 Administer a differN=4 Administer a nonioN=10 Premedication Moderate reaction resemsymptoms) N=28 (0.004%) For GadN=29 (0.046%) For GadN=0 For Gadodiamide 

Murphy, K.P. et al. (1999) 

Procedure: MRI with gadoliniumbased contrast (Magnevist, Prohance, Omniscan) Setting: Includes 

freestanding clinics (Academic) Design: Population-based cross-sectional 

N=53 American Society of Neuroradiology program directors representing 105 centers and 835,535 doses of MR contrast No sample description available

Inclusion:Director of fellowship program of “American Society of Neuroradiology in the United States and Canada” 

Not specified 

Adverse symptoms or signs 

Provider questionnaire 

Moderate reaction crossN=9 No precautions for N=0 No precautions for N=12 Noncontrast MRI N=20 Noncontrast MRI administration N=0 Administer a differN=8 Administer a nonioN=19 Premedication 
64 

Severe reaction (respiraedema) N=5 (0.001%) For GadoN=11 (0.017%) For GadN=0 For Gadodiamide Severe reaction cross-taN=9 No precautions for N=0 No precautions for N=18 Noncontrast MRI N=24 Noncontrast MRI administration N=0 Administer a differN=3 Administer a nonioN=16 Premedication Overall/total number adN=454 (0.066%) For G

N=260 (0.406%) For GN=23 (0.031%) For Gad
65 

N= 66 (25.2%) Patients (Gadoversetamide) N=31 (23.3%) Patients (Gadopentetate dimegluN=5 (1.9%) Patients Se(Gadoversetamide) N=4 (3.8%) Patients Sedimeglumine) N=3 Reports Headache N=1 Report Chest pain N=1 Report Leg cramp N= 1 Report UTI (GadoN=1 Report Back pain (N=1 Report Vasospasm N=1 Report Vasodilatatdimeglumine) N= 1 Report Taste pervdimeglumine) N=6 (2.3%) Injection asN=6 (4.5%) Injection asdimeglumine) N=27 (10.3%) Injection (Gadoversetamide) N=18 (13.5%) Injection dimeglumine) 

Grossman, R.I. et al. (2000) 

Procedure: MRI with Gadoversetamide (OptiMark=GdDTPA-BMEA) vs. gadopentetate dimeglumine (Magnevist=GDDTPA) Setting: Not 

specified Design:Randomized clinical trial 

N=395 Patients Sample Description: Mean age 45.0 +/- 14.8 years (Gadoversetamide), 44.5 +/- 14.1 years (Gadopentetate dimeglumine) 

Inclusion: Known or highly suspected CNS pathology; qualifying contrast-enhanced MRI within 8 weeks before study enrollment Exclusion:Pregnant, lactating, patients previously entered in this study or those who had taken any investigational drug within 30 days before admission into the study, patients with a hypersensitivity reaction to a gadolinium-based contrast agent, patients with a contraindication to MRI, patients who had undergone contrast-enhanced examination within 48 hours before enrollment, patients with hemoglobinopathies 

30 days Adverse 

symptoms or signs 

Not specified 

N=7 (2.7%) Injection as(Gadoversetamide) N=2 (1.5%) Injection asdimeglumine) 
66 

 N=39 (14.9%) Total inj

(Gadoversetamide) N=24 (18.0%)Total inje(Gadopentetate dimeglu

remainder mild to mode
67 

Any adverse symptom or event 

Not specified (Medical record vs. Study logs) 

N=20 (28.2%) MultiHaN=15 (23.1%) MultiHaN=22 (31.9%) Omnisca

Adverse symptom or event related to contrast 

Not specified (Medical record vs. Study logs) 

N=16 (22.5%) MultiHaN=14 (21.5%) MultiHaN=13 (18.8%) Omnisca

Headache Not specified 

(Medical record vs. Study logs) 

N=11 (15.5%) MultiHaN=1 (1.5%) MultiHancN=5 (7.2%) Omniscan (

Nausea Not specified 

(Medical record vs. Study logs) 

N=2 (2.8%) MultiHancN=2 (3.1%) MultiHancN=4 (5.8%) Omniscan (

Taste perversion Not specified 

(Medical record vs. Study logs) 

N=1 (1.4%) MultiHancN=3 (4.6%) MultiHancN=4 (5.8%) Omniscan (

Dizziness Not specified 

(Medical record vs. Study logs) 

N=1 (1.4%) MultiHancN=3 (4.6%) MultiHancN=2 (2.9%) Omniscan (

Vasodilation Not specified 

(Medical record vs. Study logs) 

N=2 (2.8%) MultiHancN=2 (3.1%) MultiHancN=0 Omniscan (0.3 mm

Significant change in vital signs 

Not specified N=0 

Significant electrocardiogram changes 

Not specified N=0 

Runge, V.M. et al. (2001)

Procedure: MRI with gadobenate dimeglumine (MultiHance) at 0.15 mmol/kg, 0.2 mmol/kg vs. Gadodiamide (Omniscan) at 0.3 mmol/kg Setting: Not specified Design:Randomized clinical trial 

N=205 patients Sample Description: 53% Female;14% Minority 

Inclusion: High suspicion of one or more CNS lesions based on the results of a prior diagnostic imaging evaluation, which must have been obtained from 2 months to 24 hours before study agent administration with no intervening therapy. 

60 days (for efficacy portion of study; unclear if 24 hours for safety portion of study) 

Significant lab value changes (hematology, serum chemistry, urinalysis) 

Not specified N=0 

Note: Sample Size/Sample Description cell includes descriptive information about the sample including (where available): basic demographics (age, gender, racharacteristics (Medicare, VA, etc.).
68
69

APPENDIX A.3 

COLONOSCOPY EVIDENCE TABLES 

Author and 

Date

Procedure, 

Provider 

Performing 

Procedure, Study 

Setting, & Study 

Design

Sample Size/ 

Description

Inclusion/ 

Exclusion Criteria

Study 

Follow-Up Measure

Method of 

Measure 

Assessment

Process Measures 

Sedation procedures 

Medical record Meperidine – 25 to 50 m

2.5 mg intravenously. Butorphanol tartrate – 2 

Bowel cleansing Medical record 2 bottles magnesium cit

water. P.M. patients – commerelectrolyte solution bowMajority had 1000cc intreturns were clear. 

Reach-thececum-rate Medical record 83% Complete colonoscopies: 

Medical record With barium enema: 22

Without barium enema: 

Godreau, C.J., et al. (1992) 

Procedure: Colonoscopy, barium enema Provider: Family medicine Setting:

Physician’s office. Design: Case series 

N = 112 patients (N = 157 colonoscopies) Sample description:Mean age: 58 Female: 57% 

Not specified 2 days 

Incomplete colonoscopies: 

Medical record With barium enema: 6/

Without barium enema: (6 due to severe diverticcarcinoma) 
70 

Waye, J.D. et al. (1992) 

Procedure:Colonoscopy Provider:Endoscopist Setting:Ambulatory surgical center Design: Case series 

N = 2,097 colonoscopies (N = 777 received polypectomies; N = 1,320 diagnostic) Sample description:Mean age: 64.9 Female: 37% 

Exclusion:Penicillin allergy in patients requiring prophylactic antibiotics; Patients who absolutely required contiguous anticoagulation. 

5 days Sedation 

procedures 

Medical record I.V. meperidine & diaze
71 

Termination of exam due to poor preparation 

Data sheet completed by physician 

7% terminated with pur30% terminated with lax

Transverse colon reached 

Data sheet completed by physician 

Sedated: 92% Nonsedated: 62%, p<0 

Average insertion depth 

Data sheet completed by physician 

Sedated: 134 cm. Nonsedated: 81 cm, p<0

Reason for stopping procedure: Cecum reached 

Data sheet completed by physician 

Sedated: 74%; Non-sed

Reason for stopping procedure: Inadequate preparation 

Data sheet completed by physician 

Sedated: 11%; Non-sed

Reason for stopping procedure: Unable to traverse lumen 

Data sheet completed by physician 

Sedated: 8%; Non-seda

Reason for stopping procedure: Pain 

Data sheet completed by physician 

Sedated:5%; Non-sedat

Reason for stopping procedure: Obstruction 

Data sheet completed by physician 

Sedated: 2%; Non-seda

Turn-around maneuver performed 

Data sheet completed by physician 

Sedated: 93%; Non-sed

Rodney, W.M. et al. (1993a) 

Procedure:Colonoscopy Provider: Family medicine Setting:Physician’s office. (Academic, urban) Design: Cohort 

N = 164 (N = 126 sedated; N = 38 nonsedated). Sample description:Mean age: Sedated – 55; Nonsedated – 58 Female: Sedated – 56% Nonsedated – 61% 

Not specified 2 days 

Procedure time Data sheet 

completed by physician 

Sedated: 32 minutes, ra 120 minutes; Nonsedated: 27 minutes 60 minutes, p<0.07 
72 

Length of colonoscopy procedure 

Medical record 30 – 45 minutes 

Cecum reached Medical record All procedures: 48% 

Patient with prior abdom

Patient without prior su

Unable to traverse lumen 

Medical record 30% of cases 

Termination of procedure because of pain 

Medical record 13% of cases 

Rodney, W.M. et al (1993b) 

Procedure:Colonoscopy Provider: Family medicine Setting:Physician’s office Design: Cohort 

N = 293 colonoscopies (N = 241 patients) Sample description:Mean age: 67 Female: 61% 

Not specified > 12 

months 

Termination of procedure because of inadequate bowel preparation

Medical record 3% of cases 

1 hour Oxygen 

saturation 

Medical record Monitored continuously 

initiated before sedation

Poser, G. et al. (1995) 

Procedure:Colonoscopy , gastroscopy Provider: Not specified Setting: Hospital outpatient department Design: Case series 

N = 475 participants (N = 262 colonoscopy; N = 55 colonoscopy & gastroscopy combined) Sample description:Mean age: Colonoscopy – 59.2 Combined – 56.9 Female: 55% 

Inclusion:18 or older; Received only meperidine and/or midazolam Exclusion:Language barrier; Senility; Inability to obtain oxygen saturation on readings with finger sensor; Insufficient staff to gather data 

 Vital signs and 

level of consciousness 

Medical record Recorded every 5 minut

Upon admission recorde
73 

Hopper, W. et al. (1996) 

Procedure:Colonoscopy Provider: Family Medicine Setting: Hospital outpatient & physician’s office (Rural, community) Design: Case series 

N = 1,048 colonoscopies Sample description:Mean age: 57 +/- 15; Female: 41% 

Not specified Not 

specified 

Cecum reached Operative report 

(log) 

No medication: 121/135 (36%) All medicated: 662/713 (93%) Sedation/analgesia (mep556/603 (92%) Analgesic (ketorolac onSedated (non-ketorolac)

Length of procedure 

Medical record Upper endoscopy – ave

Colonoscopy – average Dual procedures – avera

Lugay, M. et al. (1996) 

Procedure:Colonoscopy, upper endoscopy Provider: Not specified Setting: Hospital outpatient department, ambulatory surgical center Design: Case series 

N = 405 patients Sample description:Mean age: 62; Female: 55% 

Inclusion: Cognitively intact; Received meperidine, diazepam, midazolam, and/or naloxone; Adult 

2 days 

Type of conscious sedation 

Medical record Meperidine & diazepam

Meperidine & midazola(14.6%) Meperidine, diazepam oNo sedation: 1 subject 
74 

Sedation procedures 

Medical record Meperidine – 656/713 (

100mg). Midazolam – 731/743 (14mg). 

Area reached Medical record 91.5% intubated cecum 

94.1% reached ascendin99.3% reached transver

Pierzchajlo, R.P.J. et al. (1997) 

Procedure: Colonoscopy Provider: Family medicine

Setting: Hospital outpatient department Design: Case series 

N = 751 colonoscopies (555 patients) Sample description:Mean age: 53.8 +/- 18.1 Female: 62% 

Not specified Not 

specified 

Cecum reached by quality of preparation 

Medical record Excellent bowel prepara

Fair prep: 115 of 131 (8Poor prep: 9 of 20 (45%comparison) Men = 96.9% Women = 88%, (p<0.00

Mean duration of diagnostic colonoscopy 

Medical record 21 +/- 13 minutes 

Mean duration of colonoscopy with biopsy 

Medical record 30 +/- 16 minutes 

Mean duration of colonoscopy with polypectomy 

Medical record 41 +/- 25 minutes 

Intravenous sedation 

Medical record Received by all patients 

Midazolam received by mg) 84% received meperidin

Galandiuk, S. et al. (1998) 

Procedure:Colonoscopy Provider:Gastroenterologist, surgeon, surgical resident Setting: Hospital outpatient department (Academic) Design: Case series 

N = 1,004 Sample description:Mean age: 54 +/- 15 

Not specified Not 

specified 

Cecum reached Medical record Gastroenterologists = 94

Surgeons = 94% Surgical residents = 93% 
75 

Cecum could not be intubated 

Medical record 73 cases due to: 

 Narrowing stricture (3 Redundancy (18)  Poor preparation (14)  Other (8) 

Average procedure time 

Medical record Recorded in 1,023 cases

34.7 minutes (range 5-1

Wexner, S.D. et al. (1998) 

Procedure:Endoscopy, colonoscopy Provider:Surgeon Setting: Hospital outpatient department Design: Case series 

N = 2,069 patients Sample description:Mean age: 65 

Not specified 3 months 

Average sedation doses 

Medical record Recorded in 1,023 cases

 2.1 (range 1.5-10 mg)  75.2 (range 25-225 mgNo major complication patients. 

7 days Length of time 

to complete procedure 

Patient questionnaire 

Unplanned work absencPlanned work absence = 

Newcomer, M.K. et al. (1999) 

Procedure:Colonoscopy Provider: Not specified Setting:Physician’s office. (Community and urban population) Design: Case series 

N = 250 patients Sample description Mean age: Planned work absence: 44.8 +/- 13.0; Unplanned work absence: 52.4 +/- 8.8 % Female: Planned absence: 80% Unplanned absence: 40.8% 

Inclusion:Age 18 – 70 years old; Employed full-time or parttime to work the day following the procedure 

 Sedation Patient 

questionnaire 

Midazolam: Un-planned = 3.2 mg (1Planned = 2.3 mg (1.1) Fentanyl Unplanned = 0.3 mg (0Planned = 0.14 mg (0.2
76 

Cecum reached Medical record 69/69 (100%) Mean time to reach cecum 

Medical record Routine sedation: 5.2 +/

As-needed sedation: 8.0 

Rex, D.K. et al. (1999) 

Procedure:Colonoscopy Provider:Gastroenterologist Setting: Hospital outpatient department, inpatient (Academic, community) Design:Randomized clinical trial 

N = 69 patients (Routine sedation = 35; Sedation as needed = 34) Sample description: Mean age: Routine sedation  – 61.2 years old; Sedation as needed  – 61.6 years old Female: Routine sedation = 31%; Sedation as needed = 21% 

Exclusion:Inpatient; Outpatient simultaneously undergoing colonoscopy & upper endoscopy; Unable to give informed consent.; “Severe illness or preexisting discomfort” in physician’s opinion. 

4 months 

Mean time from completion of colonoscopy to discharge (min) 

Medical record Routine sedation: 54.6 +

As-needed sedation: 10

Sedation type Medical record Midazolam used in 129 

(Median dose – 2mg); 7received fentanyl (medi40% no sedation (of all 

Clarke, G.A. et al. (2001) 

Procedure:Colonoscopy (43.3%), EGD, ERCP Provider: Not specified (comes from division of GI) Setting: Hospital outpatient department, inpatient (35% of all procedures) (Academic, urban) Design: Case series 

N = 214 patients (N = 95 colonoscopy) Sample description: Mean age: 87; Female: 40% 

Inclusion:> 85 years old 

Not specified 

Topical anesthesia benzocaine 

Medical record 100% 
77 

Nelson, D.B., et al. (2002) 

Mean insertion time to cecum 

Medical record 10.5 minutes (± 8.7) 

Nelson, D.B., et al. (2002) 

Mean total procedure time 

Medical record 30.6 minutes (± 19.1) 

Nelson, D.B. et al. (2002) 

Procedure: Colonoscopy Provider:Gastroenterologists Setting: Hospital 

outpatient department (Veteran’s Administration) Design: Case series

N=3,196 Sample description:Mean age: 63.0; Female: 3.2% Non-White: 16.5% 

Inclusion: Age 50-75, no history of colonoscopy in the previous ten years, used VA facilities Exclusion: Patient reported lower GI tract disease in prior six months, significant change in bowel habits, lower abdominal pain that requires evaluation, prior colonic disease, significant medical problems that could increase the risk of colonoscopy, cancer, terminal illness, need for special precautions with colonoscopy (anti-coagulation, antibiotics), women of childbearing age 

Nelson, D.B., et al. (2002) 

Bowel preparation 

Medical record Good: 81.4% 

Fair: 15.8% Poor: 2.7% 
78 

Length of procedure 

GI-Trac endoscopy reporting system 

27% of endoscopists too73% of cases took 20-4

Cotton, P.B. et al. (2003) 

Procedure:Colonoscopy Provider:Endoscopist Setting: Hospital outpatient dept. (Academic, VA, Air Force, and one Canadian academic setting.) Design:Population-based cross-sectional 

17,868 colonoscopies 69 endoscopies Sample description: Mean age = 50-59 for 95% of endoscopists. 

Not specified Not 

specified 

Cecal intubation rate 

GI-Trac endoscopy reporting system 

55% of endoscopists acMedian value = 88% 9% achieved rate under 19% achieved 85% - 89

Sedation type Not specified Propofol mean dose: 

For colonoscopy, 210 mFor Colonoscopy + uppmg) 

Walker, J.A. et al. (2003) 

Procedure:Colonoscopy, EGD, & liver biopsy Provider:Gastroenterologist, nurse Setting:Ambulatory surgical center (Community) Design: Case series 

N = 9,152 cases (N = 2000 given questionnaire; N = 1,009 returned questionnaire). Sample description:Age range 7.5 – 96 

Exclusion:Pregnant, allergy to propofol 

Not specified 

Physician ratings of propofol vs. midazolam/ meperidine 

Physician questionnaire 

(1 – very strongly disagSafer and smoother titraMore relaxed ambienceProcedure is faster: 3.8 Better memory at dischMore rapid discharge: 4Quicker to get started: 4Better patient toleranceBetter reputation in the More procedures in a fi

Note: Sample Size/Sample Description cell includes descriptive information about the sample including (where available): basic demographics (age, gender, racharacteristics (Medicare, VA, etc.). 
79 

Complications Related to Colonoscopy 

Acute bleeding Medical record 11 patients (0.5%) Late bleeding (1 – 12 days after examination) 

Medical record 15 patients (0.7%) 

Postpolypectomy syndrome (“related to a full thickness thermal injury to the colon wall” p.348). 

Medical record 9 patients (0.4%) 

Waye, J.D. et al. (1992) 

Procedure:Colonoscopy Provider:Endoscopist Setting:Ambulatory surgical center Design: Case series 

N = 2,097 colonoscopies Sample description:Mean age: 64.9 Female: 37% 

Exclusion:Penicillin allergy in patients requiring prophylactic antibiotics; Patients who absolutely required contiguous anticoagulation. 

12 days 

Delayed perforation 

Medical record 2 (0.1%) 

Rosen, L. et al. (1993) 

Procedure:Colonoscopy, polypectomy Provider: Gastroenterologist, colorectal surgeon Setting: Hospital outpatient department Design: Case series 

N = 16,910 colonoscopies (N = 4,721 had polypectomies; N = 20 hospitalized) Sample description: (N = 20) Mean age: 68 Female: 33% 

Not specified Not 

specified 

Bleeding from polypectomy 

Medical record 9 – had primary bleedin

11 – had delayed bleedi(Note: doesn’t specify h
80 

Rodney, W.M. et al. (1993a) 

Procedure:Colonoscopy Provider: Family medicine Setting:Physician’s office. (Academic, urban) Design: Cohort 

N = 164 (N = 126 sedated; N = 38 nonsedated) Sample description:Mean age: Sedated – 55; Nonsedated – 58 Female: Sedated – 56% Nonsedated – 61% 

Not specified 2 days Pain Data sheet 

completed by physician 

1 patient reported left loprocedure. 

Minor bleeding Patient 

questionnaire 

Using NSAID: 20 (8.8%No NSAID: 6 (2.5%) 

Shiffman, M.L. et al. (1994) 

Procedure:Colonoscopy, polypectomy Provider: Not specified Setting: Hospital outpatient department Design: Cohort 

N = 464 Sample description:Mean age: 59.1 Female: 22% All with VA insurance coverage. 

Exclusion:Hospitalization at time of procedure, patient took coumadin or heparin within 2 weeks of procedure, patient had active gastrointestinal bleeding, patient had gastrointestinal malignancy, patient with known history of bleeding 

42 days 

Major bleeding Patient 

questionnaire 

Using NSAID: 2 (0.9%No NSAID: 2 (0.9%) 
81 

Hopper, W. et al. (1996) 

Procedure:Colonoscopy Provider: Family Medicine Setting: Hospital outpatient & physician’s office. (Rural, community). Design: Case series 

N = 1,048 colonoscopies Sample description:Mean age: 57 +/- 15; Female: 41% 

Not specified Not 

specified 

Perforations Operative report None 
82 

Intra-operative pain 

Medical record 29% 

Intra-operative hypertension 

Medical Record 15% 

Intra-operative hypotension 

Medical Record 14% 

Intra-operative bradycardia 

Medical Record 12% 

Post-procedure weakness 

Medical record 44% 

Post-procedure abdominal pain 

Medical Record 25% 

Post-procedure dizziness 

Medical Record 23% 

Post-procedure hypotension 

Medical Record 15% 

Post-procedure bradycardia 

Medical record 10% 

Dizzy/lightheaded within 48 hours of discharge 

Medical record 7% 

Weakness within 48 hours of discharge 

Medical record 5% 

Nausea within 48 hours of discharge 

Medical record 3% 

Lugay, M. et al. (1996) 

Procedure:Colonoscopy,, upper endoscopy Provider: Not specified Setting: Hospital outpatient department, ambulatory surgical center Design: Case series 

N = 405 patients (N=289 colonoscopy patients) Sample description:Mean age: 62; Female: 55% 

Inclusion: Cognitively intact; Received meperidine, diazepam, midazolam, and/or naloxone; Adult 

2 days 

Vomiting within 48 hours of discharge 

Medical record 1% 
83 

Galandiuk, S. et al. (1998) 

Procedure:Colonoscopy Provider:Gastroenterologist, surgeon, surgical resident Setting: Hospital outpatient department (Academic) Design: Case series 

N = 1,004 Sample description:Mean age: 54 +/- 15 

Not specified Not 

specified 

Bleeding Medical record 2 patients (.02%) Perforations after polypectomy 

Wexner, Medical record 3 episodes (0.8%), (2 haS.D. et al. (1998) 

Procedure:Endoscopy, colonoscopy Provider:Surgeon Setting: Hospital outpatient department Design: Case series 

N = 2,069 patients Sample description:Mean age: 65 

Not specified 3 months 

Bleeding after polypectomy 

Medical record 2 episodes (0.6%) 
84 

Newcomer, M.K. et al. (1999) 

Procedure:Colonoscopy Provider: Not specified Setting:Physician’s office. (Community and urban population) Design: Case series 

N = 250 patients Sample description Mean age: Planned work absence =  44.8 +/- 13; Unplanned work absence  = 52.4 +/- 8.8 Female: Planned absence = 80%; Unplanned = 40.8% 

Inclusion:Age 18 – 70 years old; Employed full-time or parttime to work the day following the procedure 

7 days Reason for 

missed work 

Patient questionnaire 

Feeling sleepy or weak: Abdominal pain or bloaFeeling sleepy or weak or bloating: 2 (0.01%) Rectal pain: 1 (0.004%) 

Complications reported 30 days postcolonoscopy 

Patient questionnaire & telephone interview 

Abdominal discomfort: Rectal bleeding: 22 (1.8Altered bowel habits: 1Oversedation, fatigue: 1Gas: 14 (1.2%) Nausea, vomiting: 14 (1Musculoskeletal pain: 1Rectal discomfort, irritaGenitourinary problemsDizzy, syncope (N=1): Loss of appetite: 2 (0.2%Headaches: 1 (0.1%) Rash: 2 (0.2%) Shortness of breath: 1 (0

Zubarik, R. et al. (1999) 

Procedure:Colonoscopy Provider:Gastroenterologist, pediatric gastroenterologist, and colorectal surgeon. Setting: Hospital outpatient setting. (Academic) Design: Case series 

N= 1196 patients interviewed Sample description:Mean age: 56.7 Female: 47% 

Exclusion:Didn’t answer phone for questioning; Hospitalizations that were result of findings at colonoscopy but not caused by a complication 

30 days 

Postpolypectomy bleeding 

Patient questionnaire & telephone interview 

31 (2.6%) 
85 

Perforation rate, site of perforation, cause of perforation, and timing of perforation 

Medical record 20 (0.19%) 

Site: Sigmoid colon – 13 (65Splenic flexure – 1 (5%Ascending colon – 1 (5%Cecum – 5 (25%) Cause: Mechanical – 7 (32%) Electrocautery – 8 (36%Barotrauma – 1 (5%) Unclear/multifactorial – Timing: Day 14+: 2 (9%) Day 2: 3 (14%) Day 1: 2 (9%) Day 0: 15 (68%) 

Rate of perforation overall 

Medical record Male: 0.19% (0.5-0.49) 

Female: 0.52% (0.21-1.

Anderson, M.L. et al. (2000) 

Procedure:Colonoscopy, sigmoidoscopy Provider:Gastroenterologist Setting: Hospital outpatient department (Academic). Design: Case control 

N = 10,486 colonoscopies Sample description:Mean age: 72 (Range: 48 - 87) Female: 63.6% 

Inclusion:True colonic perforation after colonoscopy or flexible sigmoidoscopy. Exclusion:Postpolypectomy syndrome 

> 2 weeks 

Perforation by procedure indication 

Medical record Therapeutic – 8 (40% o

Diagnostic – 12 (60% o

Timothy, S.K.C. et al. (2001) 

Procedure:Colonoscopy, Barium Enema Provider:Surgeon Setting: Hospital outpatient department Design: Case series 

N = 94 patients (N = 109 cases). Diagnostic = 58 cases. Therapeutic = 51 cases. Sample description: Mean age: 70 Female: 42% 

Inclusion:Patients receiving oral anticoagulation 

2 months Hemorrhagic 

complication 

Medical record 1 therapeutic case (1.95

0 diagnostic cases Entire patient group rate 
86 

Clarke, G.A. et al. (2001) 

Procedure:Colonoscopy (43.3%), EGD, ERCP Provider: Not specified (comes from division of GI) Setting: Hospital outpatient department, inpatient (35% of all procedures) (Academic, urban) Design: Case series 

N = 214 patients (N = 95 colonoscopy) Sample description: Mean age: 87; Female: 40% 

Inclusion:> 85 years old 

Not specified 

Perforation Medical record 1 (1%) 
87 

Abdominal discomfort 

Patient questionnaire 

Colonoscopy: 21 (5.3%Colo. + EGD: 8 (9.3%) 

Sore throat Patient 

questionnaire 

Colonoscopy: 11 (2.8%Colo. + EGD: 11 (12.8%

Nausea or vomiting 

Patient questionnaire 

Colonoscopy: 15 (3.8%Colo. + EGD: 6 (7.0%) 

Shortness of breath 

Patient questionnaire 

Colonoscopy: 15 (3.8%Colo. + EGD: 4 (4.7%) 

Headache Patient 

questionnaire 

Colonoscopy: 10 (2.5%Colo. + EGD: 2 (2.3%) 

Rectal bleeding Patient 

questionnaire 

Colonoscopy: 11 (2.8%Colo. + EGD: 4 (4.7%) 

Change in bowel habits 

Patient questionnaire 

Colonoscopy: 11 (2.8%Colo. + EGD: 4 (4.7%) 

Pain in intravenous site 

Patient questionnaire 

Colonoscopy: 8 (2.0%); Colo. + EGD: 1 (1.2%) 

Dizziness Patient 

questionnaire 

Colonoscopy: 8 (2.0%); Colo. + EGD: 0 (0%) 

Fatigue Patient 

questionnaire 

Colonoscopy: 2 (0.5%); Colo. + EGD: 2 (2.3%) 

Musculoskeletal pain 

Patient questionnaire 

Colonoscopy: 1 (0.3%); Colo. + EGD: 2 (2.3%) 

Hoarseness Patient 

questionnaire 

Colonoscopy: 0 (0%); Colo. + EGD: 2 (2.3%) 

Mild chest pain Patient 

questionnaire 

Colonoscopy: 0 (0%); Colo. + EGD: 1 (1.2%) 

Decreased appetite 

Patient questionnaire 

Colonoscopy: 1 (0.3%); Colo. + EGD: 0 (0%) 

Fever Patient 

questionnaire 

Colonoscopy: 1 (0.3%); Colo. + EGD: 1 (1.2%) 

Nocturia Patient 

questionnaire 

Colonoscopy: 0 (0%); Colo. + EGD: 1 (1.2%) 

Bini, E.J. et al. (2002) 

Procedure:Endoscopy, colonoscopy, sigmoidoscopy, EGD Provider:Gastroenterologist Setting: Hospital outpatient department. (Academic). Design: Cohort 

N = 400 (Colonoscopy only); N = 86 (Colonoscopy & EGD) Sample description:Not specified 

Not specified 30 days 

30-day frequency of negative outcomes 

Patient questionnaire 

Colonoscopy: 15%; Colo. + EGD: 24.4% 
88 

Perforation Medical record 0 (0%) GI bleeding with hospitalization 

Medical record 7 (0.22%) 

Thrombosed carotidsubclavian bypass 

Medical record 1 (<0.01%) 

Fournier’s gangrene of perineum 

Medical record 1 (<0.01%) 

Total major complications 

Medical record 18 (0.56%) 

Minor GI bleeding 

Medical record 6 (0.22%) 

Vasovagal events 

Medical record 188 (5.4%) 

Abdominal pain lasting >2 hours 

Medical record 24 (0.8%) 

Nelson, D.B. et al. (2002) 

Procedure: Colonoscopy Provider:Gastroenterologists Setting: Hospital 

outpatient department (Veteran’s Administration) Design: Case series

N=3,196 Sample description:Mean age: 63.0; Female: 3.2% Non-White: 16.5% 

Inclusion: Age 50-75, no history of colonoscopy in the previous ten years, used VA facilities Exclusion: Patient reported lower GI tract disease in prior six months, significant change in bowel habits, lower abdominal pain that requires evaluation, prior colonic disease, significant medical problems that could increase the risk of colonoscopy, cancer, terminal illness, need for special precautions with colonoscopy (anti-coagulation, antibiotics), women of childbearing age 

1 month 

Other minor complications 

Medical record 125 (3.9%) 
89 

Perforation rate GI-Trac 

endoscopy reporting system 

Cotton, P.B. .07% (range .03% - .17%et al. (2003) 

Procedure:Colonoscopy Provider:Endoscopist Setting: Hospital outpatient department (Academic, VA, Air Force, and one Canadian academic setting) Design:Population-based cross-sectional 

17,868 colonoscopies Sample description: Mean age = 50-59 years old for 95% of endoscopists. 

Not specified Not 

specified 

Bleeding GI-Trac 

endoscopy reporting system 

.17% (range .07% - .26%

Korman, L.Y. et al. (2003) 

Procedure:Colonoscopy Provider: Gastroenterologist and Endoscopist. Setting: Ambulatory surgical center. Design: Case series 

N = 116,000 colonoscopies Sample description:Mean age = 69.4 Female = 73% 

Not specified 4 days Perforation Provider 

questionnaire 

37 of 116,000 colonosc23 (62%) occurred in si6 (16%) occurred in cec4 (11%) occurred in tran 4 (11%) occurred in recunknown site. 
90 

Gatto, N.M. et al. (2003) 

Procedure:Colonoscopy, sigmoidoscopy Provider: Not specified Setting: Inpatient, hospital outpatient department, ambulatory surgical center, physician’s office Design:Population based cross-sectional 

N = 39,286 colonoscopies Sample description:Mean age: 74; Female: 57% Minority race/ ethnicity: 16% 

Inclusion:Age > 65 years old; had at least one colonoscopy/ sigmoidoscopy billed to Medicare between 1991 – 1998; cancer-free; reside in SEER region. 

30 days Perforation Administrative 

data 

77 subjects with intestin(1.96 per 1000 procedurPatients 75 – 77 years o[1.7 – 8.2]. Patients 80+ at higher ri

Perforation Provider log 7 colonic perforations Bleeding Provider log 2 cases Abdominal pain Provider log 2 cases 

Walker, J.A. et al. (2003) 

Procedure:Colonoscopy, EGD, & liver biopsy Provider:Gastroenterologist, nurse Setting:Ambulatory surgical center (Community) Design: Case series 

N = 9,152 cases Sample description:Age range 7.5 – 96 

Exclusion:Pregnant, allergy to propofol 

Not specified 

Hemiparesis Provider log 1 in a patient with know

attacks 

Note: Sample Size/Sample Description cell includes descriptive information about the sample including (where available): basic demographics (age, gender, racharacteristics (Medicare, VA, etc.). 
91 

Complications Unrelated to the Colon: Sedation Complications Poser, G. et al. (1995) 

Procedure:Colonoscopy , gastroscopy Provider: Not specified Setting: Hospital outpatient department Design: Case series 

N = 475 participants (N = 262 colonoscopy; N = 55 colonoscopy & gastroscopy combined) Sample description:Mean age: Colonoscopy – 59.2 Combined – 56.9 Female: 55% 

Inclusion:18 years old or older; Received only meperidine and/or midazolam Exclusion:Language barrier; Senility; Inability to obtain oxygen saturation on readings with finger sensor; Insufficient staff to gather data 

1 hour Oxygen 

desaturation 

Medical record 115 (24% of 475) evide

Only 10.4% desaturatin0 incidents in last 10 mi71 (61%) were smokers 45 years old and younge59 years old and higherdesaturation 

Lugay, M. et al. (1996) 

Procedure:Colonoscopy,, upper endoscopy Provider: Not specified Setting: Hospital outpatient department, ambulatory surgical center Design: Case series 

N = 405 patients (N=289 colonoscopy patients) Sample description:Mean age: 62; Female: 55% 

Inclusion: Cognitively intact; Received meperidine, diazepam, midazolam, and/or naloxone; Adult 

2 days Intra-operative 

oxygen desaturation 

Medical record 23% 
92 

Pierzchajlo, R.P.J. et al. (1997) 

Procedure: Colonoscopy Provider: Family medicine

Setting: Hospital outpatient department Design: Case series 

N = 751 colonoscopies (555 patients) Sample description:Mean age: 53.8 +/- 18.1 Female: 62% 

Not specified Not 

specified 

Medical intervention due to IV anesthesia 

Medical record 5 (0.9%) 

Conditions: oxygen desbradycardia, erythema & 

Galandiuk, S. et al. (1998) 

Procedure:Colonoscopy Provider:Gastroenterologist, surgeon, surgical resident Setting: Hospital outpatient department. (Academic) Design: Case series 

N = 1,004 Sample description:Mean age: 54 +/- 15 

Not specified Not 

specified 

Minor sedation complications 

Medical record 174 patients: (13 had > 

BP systolic > 180 mm HBP systolic< 80mm Hg Arrhythmia – 58 (6%) SaO2 < 90% - 69 (7%) Unresponsiveness – 2 (0Minor sedation-related frequently in patients rewithout concomitant me
93 

Number of patients given supplemental oxygen 

Medical record Routine sedation: 9; 

As-needed sedation: 0, p

Number of patients with diaphoresis 

Medical record Routine sedation: 3; 

As-needed sedation: 2, N

Rex, D.K. et al. (1999) 

Procedure:Colonoscopy Provider:Gastroenterologist Setting: Hospital outpatient department, inpatient (Academic, community) Design:Randomized clinical trial 

N = 69 patients (Routine sedation = 35; Sedation as needed = 34) Sample description: Mean age: Routine sedation  – 61.2; Sedation as needed  – 61.6 Female: Routine sedation – 31%; Sedation as needed – 21% 

Exclusion:Inpatient; Outpatient simultaneously undergoing colonoscopy & upper endoscopy; Unable to give informed consent.; “Severe illness or preexisting discomfort” in physician’s opinion. 

4 months 

Mean maximum decline in systolic blood pressure 

Medical record Routine sedation: 21.4m

As-needed sedation: 12

Clarke, G.A. et al. (2001) 

Procedure:Colonoscopy (43.3%), EGD, ERCP Provider: Not specified (comes from division of GI) Setting: Hospital outpatient department, inpatient (35% of all procedures) (Academic, urban) Design: Case series 

N = 214 patients (N = 95 colonoscopy) Sample description: Mean age: 87; Female: 40% 

Inclusion:> 85 years old 

Not specified 

Cardiopulmonary complication in sedated patients 

Medical record 0.6% of total sample 
94 

Nelson, D.B. et al. (2002) 

Procedure: Colonoscopy Provider:Gastroenterologists Setting: Hospital 

outpatient department (Veteran’s Administration) Design: Case series

N=3,196 Sample description:Mean age: 63.0; Female: 3.2% Non-White: 16.5% 

Inclusion: Age 50-75, no history of colonoscopy in the previous ten years, used VA facilities Exclusion: Patient reported lower GI tract disease in prior six months, significant change in bowel habits, lower abdominal pain that requires evaluation, prior colonic disease, significant medical problems that could increase the risk of colonoscopy, cancer, terminal illness, need for special precautions with colonoscopy (anti-coagulation, antibiotics), women of childbearing age 

1 month Oxygen 

desaturation requiring supplemental oxygen 

Medical record 141 (4.4%) 

Note: Sample Size/Sample Description cell includes descriptive information about the sample including (where available): basic demographics (age, gender, racharacteristics (Medicare, VA, etc.).
95 

Complications Unrelated to the Colon: Medical Complications, Hospitalization, Death 

Cardiovascular complications (developed hypotension during diagnostic colonoscopy) 

Waye, J.D. Medical record 3 patients (0.1%) et al. (1992) 

Procedure:Colonoscopy Provider:Endoscopist Setting:Ambulatory surgical center Design: Case series 

N = 2,097 colonoscopies Sample description:Mean age: 64.9 Female: 37% 

Exclusion:Penicillin allergy in patients requiring prophylactic antibiotics; Patients who absolutely required contiguous anticoagulation. 

12 days 

Hospitalization Medical record Total: 14 (1.8%) 

Postpolypectomy bleediPostpolypectomy syndrPerforation: 2 

Rosen, L. et al. (1993) 

Procedure:Colonoscopy, polypectomy Provider: Gastroenterologist, colorectal surgeon Setting: Hospital outpatient department Design: Case series 

N = 16,910 colonoscopies (N = 4,721 had polypectomies; N = 20 hospitalized) Sample description: (N = 20) Mean age: 68 Female: 33% 

Not specified Not 

specified 

Hospitalization Medical record 20 of 4,721 who had po

required hospital admis
96 

Death Operative report 

(log) 

Hopper, W. None et al. (1996) 

Procedure:Colonoscopy Provider: Family Medicine Setting: Hospital outpatient & physician’s office (Rural, community) Design: Case series 

N = 1,048 colonoscopies Sample description:Mean age: 57 +/- 15; Female: 41% 

Not specified Not 

specified 

Hospitalization 1 (less than 24 hours – s

patient’s inguinal herniarelax patient and scope 

Not specified 

Pierzchajlo, Hospitalization Medical record 1 (0.02%) R.P.J. et al. (1997) 

Procedure: Colonoscopy Provider: Family medicine

Setting: Hospital outpatient department Design: Case series 

N = 751 colonoscopies (555 patients) Sample description:Mean age: 53.8 +/- 18.1 Female: 62% 

Not specified 

 Death Medical record None 
97 

Galandiuk, S. et al. (1998) 

Procedure:Colonoscopy Provider:Gastroenterologist, surgeon, surgical resident Setting: Hospital outpatient department (Academic) Design: Case series 

N = 1,004 Sample description:Mean age: 54 +/- 15 

Not specified Not 

specified 

Hospitalization Medical record 3 (0.3%) 

1: inadequate bowel pre1: admitted for resection 1: admitted for bleeding 

Wexner, Death Medical record None S.D. et al. (1998) 

Procedure:Endoscopy, colonoscopy Provider:Surgeon Setting: Hospital outpatient department Design: Case series 

N = 2,069 patients Sample description:Mean age: 65 years old 

Not specified 3 months 

Hospitalization Medical record 5 from major complicat

after polypectomy (1.4% 
98 

Emergency room or physician visit following procedure 

Patient questionnaire & telephone interview 

20 (1.7%) patients Patients > 65 years old. dept, physician visit, or 

Zubarik, R. et al. (1999) 

Procedure:Colonoscopy Provider:Gastroenterologist, pediatric gastroenterologist, and colorectal surgeon. Setting: Hospital outpatient setting. (Academic) Design: Case series 

N= 1196 patients interviewed Sample description:Mean age: 56.7 Female: 47% 

Exclusion:Didn’t answer phone for questioning; Hospitalizations that were result of findings at colonoscopy but not caused by a complication 

30 days 

Hospitalization required 

Patient questionnaire & telephone interview 

7 patients 

Newcomer, M.K. et al. (1999) 

Procedure:Colonoscopy Provider: Not specified Setting:Physician’s office. (Community and urban population) Design: Case series 

N = 250 patients Sample description Mean age: Planned work absence =  44.8 +/- 13.0; Unplanned work absence  = 52.4 +/- 8.8 Female: Planned absence = 80%; Unplanned = 40.8% 

Inclusion:Age 18 – 70 years old; Employed full-time or parttime to work the day following the procedure 

7 days Post procedure 

problem or complication requiring physician visit 

Patient questionnaire 

None 
99 

Death secondary to colonic perforation 

Anderson, Medical record 2 patients who had coloM.L. et al. (2000) 

Procedure:Colonoscopy, sigmoidoscopy Provider:Gastroenterologist Setting: Hospital outpatient department (Academic) Design: Case control 

N = 10,486 colonoscopies Sample description:Mean age: 72 years old (48 - 87) Female: 63.6% 

Inclusion:True colonic perforation after colonoscopy or flexible sigmoidoscopy. Exclusion:Postpolypectomy syndrome 

> 2 weeks 

Surgical treatment secondary to colonic perforation 

Medical record 7 (0.01%) (includes col

sigmoidoscopy) 

Clarke, G.A. et al. (2001) 

Procedure:Colonoscopy (43.3%), EGD, ERCP Provider: Not specified (comes from division of GI) Setting: Hospital outpatient department, inpatient (35% of all procedures). (Academic, urban). Design: Case series 

N = 214 patients (N = 95 colonoscopy) Sample description: Mean age: 87; Female: 40% 

Inclusion:> 85 years old 

Not specified 

Death Medical record None 
100 

Death Medical record 1 (0.03%) Myocardial infarction/ cerebrovascular accident 

Medical record 4 (0.12%) 

New arrhythmia Medical record 1 (0.03%) Hospitalization due to thrombophlebitis at IV site 

Medical record 1 (<0.01%) 

Nelson, D.B. et al. (2002) 

Procedure: Colonoscopy Provider:Gastroenterologists Setting: Hospital 

outpatient department (Veteran’s Administration) Design: Case series

N=3,196 Sample description:Mean age: 63.0; Female: 3.2% Non-White: 16.5% 

Inclusion: Age 50-75, no history of colonoscopy in the previous ten years, used VA facilities Exclusion: Patient reported lower GI tract disease in prior six months, significant change in bowel habits, lower abdominal pain that requires evaluation, prior colonic disease, significant medical problems that could increase the risk of colonoscopy, cancer, terminal illness, need for special precautions with colonoscopy (anti-coagulation, antibiotics), women of childbearing age 

1 month 

Hospitalization for abdominal pain 

Medical record 1 (<0.01%) 
101 

Gatto, N.M. et al. (2003) 

Procedure:Colonoscopy, sigmoidoscopy Provider: Not specified Setting: Inpatient, hospital outpatient department, ambulatory surgical center, physician’s office Design:Population based cross-sectional 

N = 39,286 colonoscopies Sample description:Mean age: 74; Female: 57% % Minority race/ethnicity: 16% 

Inclusion:Age > 65 years old.; had at least one colonoscopy/ sigmoidoscopy billed to Medicare between 1991 – 1998; cancer-free; reside in SEER region. 

 Incidence of 

death following perforation 

Administrative data 

51.9 per 1000 colonosco14-day mortality: OR: 930-day mortality: OR 7

Korman, L.Y. et al. (2003) 

Procedure:Colonoscopy Provider: Gastroenterologist and Endoscopist. Setting: Ambulatory surgical center. Design: Case series 

N = 116,000 colonoscopies Sample description:Mean age = 69.4 Female = 73% 

Not specified 4 days Death Provider 

questionnaire 

None 
102 

Walker, J.A. et al. (2003) 

Procedure:Colonoscopy, EGD, & liver biopsy Provider:Gastroenterologist, nurse Setting:Ambulatory surgical center. (Community) Design: Case series 

N = 9,152 cases (N = 2000 given questionnaire; N = 1,009 returned questionnaire). Sample description:Age range 7.5 – 96 

Exclusion:Pregnant, allergy to propofol 

Not specified 

Hospitalized Provider log 12 total (includes all typ

Note: Sample Size/Sample Description cell includes descriptive information about the sample including (where available): basic demographics (age, gender, racharacteristics (Medicare, VA, etc.). 
103

APPENDIX B.1 

ANNOTATED BIBLIOGRAPHY FOR SELECTED CATARACT ARTICLES 

Ahmed, II, N. A. Zabriskie, et al. (2002). “Topical versus retrobulbar anesthesia for combined 

phacotrabeculectomy: prospective randomized study.” J Cataract Refract Surg 28(4): 631-8. 

 PURPOSE: To compare the safety and efficacy of topical and retrobulbar anesthesia for 

combined phacotrabeculectomy. SETTING: Tertiary-care university hospital ambulatory 

surgical center. METHODS: In this prospective study, 40 consecutive patients having combined 

phacotrabeculectomy were randomized to receive topical (n = 20) or retrobulbar (n = 20) 

anesthesia. Operating conditions, patient comfort, and surgical outcome were evaluated. 

RESULTS: There was no significant between-group difference in operating conditions (P =.56), 

pain during (P =.41) or after (P =.23) surgery, or supplemental anesthesia required (P =.49). Few 

patients in either group were bothered by tissue manipulation or the microscope light, although 

more patients in the topical group were slightly bothered by touch sensation (P =.05). Chemosis, 

subconjunctival hemorrhage, and eyelid hematoma were seen almost exclusively in the 

retrobulbar group (P <.05). Inadvertent eye movement was present more frequently in the topical 

group (P =.04), although this did not pose a problem to the surgeon. CONCLUSION: Topical 

anesthesia is a safe and effective alternative to retrobulbar anesthesia for combined 

phacotrabeculectomy. 

Ascaso, F. J., I. Ayala, et al. (1997). “Prophylactic intravenous ondansetron in patients 

undergoing cataract extraction under general anesthesia.” Ophthalmologica 211(5): 292-5. 

 During the past decade the demand for outpatient surgery has grown rapidly. 

Postoperative nausea and vomiting is one of the more common undesirable consequences of 

surgery, which may significantly delay the patient's discharge from the ambulatory surgery 

center. None of the currently used antiemetic drugs is considered totally effective in abolishing 

nausea or vomiting. The purpose of this study was to compare the efficacy of ondansetron, a 

highly selective 5-hydroxytryptamine subtype-3 receptor antagonist, with that of metoclopramide 

for the prevention of postoperative emesis in patients undergoing cataract surgery. The incidence 

of postoperative nausea was significantly less in the ondansetron group than that in the 

metoclopramide group (p = 0.046). Although the incidence of vomiting was clinically less 

frequent in the ondansetron group, there were no significant differences between both treatment 

groups. To our knowledge, this is the first study to demonstrate that ondansetron is effective to 

prevent postoperative emesis after extracapsular cataract extraction. 
104

Bohigian, G. M. (1999). “A study of the incidence of culture-positive endophthalmitis after 

cataract surgery in an ambulatory care center.” Ophthalmic Surg Lasers 30(4): 295-8. 

 BACKGROUND AND OBJECTIVE: To determine the incidence of culture-positive 

endophthalmitis after cataract surgery in an ambulatory surgical care center and to analyze the 

effectiveness of povidoneiodine solution in the preoperative preparation in preventing culturepositive endophthalmitis. PATIENTS AND METHODS: A retrospective series of 19,269 

consecutive cases of cataract extraction with lens implantation over 12 years in an ambulatory 

care center was reviewed. RESULTS: Nine cases of culture-positive endophthalmitis occurred, 

for an incidence of 0.05%. The initial 4,740 cases (1985-1989) were performed without the use 

of povidone-iodine; the following 14,529 cases (1990-1996) were done using povidone-iodine. 

The incidence of culture-positive endophthalmitis was 0.08% and 0.03%, respectively. 

CONCLUSION: The incidence of culture-positive endophthalmitis in this series was very low. 

The use of 5% povidone-iodine, topically, appeared to be beneficial in reducing the incidence of 

culture-positive endophthalmitis after cataract extraction (P=0.24), but was not statistically 

significant in this retrospective series. Evaluation and methods to prevent endophthalmitis are 

difficult in retrospective clinical studies due to multiple variables and the rarity of this 

complication. 

Corey, R. P. and R. J. Olson (1998). “Surgical outcomes of cataract extractions performed by 

residents using phacoemulsification.” J Cataract Refract Surg 24(1): 66-72. 

 PURPOSE: To assess whether changes in surgical technique, resident training, and 

phacoemulsification equipment affected the complication rate for cataract extractions performed 

by residents. SETTING: Combined urban and rural setting at a tertiary care academic center and 

a general care Veterans Administration Hospital, Salt Lake City, Utah, USA. METHODS: This 

retrospective study analyzed 396 patients who had cataract surgery by phacoemulsification and 

intraocular lens implantation performed by four residents. The residents' first 50 cases were 

compared with the last 50 cases performed at the end of their training. Surgical and 1 day 

postoperative complications were examined. RESULTS: Twenty of 396 surgical cases (5.1%) 

involved complications, and the overall vitreous loss rate for the four residents was 1.8%. A 

statistically significant difference was observed between the two residents with the highest and 

lowest number of intraoperative complications (P < .05) and between the two residents with the 

highest and lowest number of 1 day postoperative complications (P < .05). The rate of posterior 

capsule rupture with vitreous loss was 2.6% in the residents' early cases; the decrease to no cases 

of posterior capsule rupture in the late cases was also statistically significant (P < .02). 

CONCLUSION: The results indicate that with proper training and supervision, residents can 

obtain an acceptably low complication rate using phacoemulsification. As their skill increased, 

they were able to use phacoemulsification successfully on more complicated cases. Individual 

skill was also an important factor in the complication rate. 
105

Golnik, K. C., C. E. West, et al. (2000). “Incidence of ocular misalignment and diplopia after 

uneventful cataract surgery.” J Cataract Refract Surg 26(8): 1205-9. 

 PURPOSE: To evaluate the incidence of ocular misalignment and diplopia after 

uneventful cataract surgery. SETTING: An outpatient private practice eye institute. METHODS: 

One hundred thirty-eight patients referred to 1 cataract surgeon were prospectively evaluated. 

Orthoptic evaluations were performed within 1 month before and then 1 day, 1 week, and 1 

month after cataract surgery. Anesthesia was by retrobulbar injection, and cataract extraction was 

done by phacoemulsification. RESULTS: Cataract surgery was performed in 118 patients. 

Preoperatively, 16 patients had ocular misalignment; 10 were phoric, 4 were intermittently 

tropic, and 2 were tropic. Follow-up evaluation was obtained for 101 patients (86%) at 1 day, 91 

(77%) at 1 week, and 88 (75%) at 1 month. A change in ocular alignment occurred in 22 of 101 

patients (22%) at 1 day, 9 of 91 (10%) at 1 week, and 6 of 88 (7%) at 1 month. Only 1 patient 

who had a change in alignment at 1 month was symptomatic. CONCLUSIONS: A persistent 

change in ocular alignment after uneventful cataract surgery occurred in 7% of patients. 

However, symptomatic diplopia was uncommon (1 in 118; 0.85%) in this relatively small series. 

Harman, D. M. (2000). “Combined sedation and topical anesthesia for cataract surgery.” J 

Cataract Refract Surg 26(1): 109-13. 

 PURPOSE: To determine whether lidocaine jelly is as efficacious as tetracaine drops for 

obtaining ocular anesthesia and to evaluate sublingual lorazepam as premedication for sedation 

in cataract surgery. SETTING: An ambulatory surgical center dedicated to ophthalmic surgery. 

METHODS: The study was divided into 2 phases. In the first, 100 patients were divided into 2 

groups of 50 each. The first group received tetracaine 0.5% drops for anesthesia. The second 

group received lidocaine 2% jelly for topical anesthesia. In the second stage, 100 patients were 

divided into 2 groups of 50 each. The first 50 patients were given 1 mg of sublingual lorazepam 

before surgery. The second group had cataract surgery without sublingual lorazepam. All 

patients were operated on by the same surgeon in an ambulatory surgical center. The technique 

was temporal clear corneal cataract surgery with foldable intraocular lens implantation. 

Exclusions from the study were the need to convert to peribulbar or retrobulbar anesthesia, 

intraocular complications, and altered mental status. RESULTS: In the first phase of the study, 

lidocaine 2% jelly was as efficacious as tetracaine 0.5% drops for topical anesthesia in cataract 

surgery. In the second phase of the study, overall, patients in the lorazepam group had less 

anxiety, greater amnesia, and lower blood pressure than those not receiving lorazepam as 

sedation for topical anesthesia. CONCLUSIONS: Lidocaine 2% jelly combined with sublingual 

lorazepam provided excellent cost-effective anesthesia and sedation for topical anesthesia in 

cataract surgery and enhanced patient satisfaction with the procedure. 
106

Holland, G. N., D. T. Earl, et al. (1992). “Results of inpatient and outpatient cataract surgery. A 

historical cohort comparison.” Ophthalmology 99(6): 845-52. 

 PURPOSE: The transition from inpatient to outpatient cataract surgery during the last 

decade was not accompanied by prospective investigation of its effect on visual outcomes or 

surgical complications. The authors performed this study to assess the impact of this transition 

on surgical results. METHODS: The authors reviewed 600 extracapsular cataract extractions 

performed by 4 experienced ophthalmic surgeons during a 36-month period; in 300 cases, 

patients were hospitalized after surgery (inpatient group), and, in 300 cases, patients were never 

hospitalized (outpatient group). The same surgical techniques were used in all cases. Visual 

outcome and rates for operative and postoperative complications were compared. RESULTS: 

There were no statistically significant differences between the inpatient and outpatient groups for 

visual acuity. Excluding patients with pre-existing nonlenticular ocular disease, a best-corrected 

visual acuity of 20/40 or better was achieved in 93.1% of inpatient cases and in 97.2% of 

outpatient cases 6 months after surgery. Postoperative, clinically apparent cystoid macular edema 

was more common in the inpatient group (P = 0.03); however, after exclusion of patients with 

diabetes, hypertension, age younger than 65 years, and eyes with pre-existing nonlenticular 

disease, there was no statistically significant difference between groups. No significant 

differences in rates for other operative and postoperative complications were identified, 

including wound dehiscence, unplanned postoperative filtering blebs, infectious endophthalmitis, 

retinal detachment, persistent iridocyclitis, glaucoma, and corneal edema. CONCLUSION: This 

study does not demonstrate that the transition to outpatient cataract extractions has had an 

adverse effect on surgical outcomes. 

Javitt, J. C., D. A. Street, et al. (1994). “National outcomes of cataract extraction. Retinal 

detachment and endophthalmitis after outpatient cataract surgery. Cataract Patient Outcomes 

Research Team.” Ophthalmology 101(1): 100-5; discussion 106. 

 BACKGROUND: A near-total shift to cataract extraction on an outpatient basis occurred 

as a result of an administrative ruling by the Health Care Financing Administration. No national 

study has been conducted to assess the possible effects of that decision on clinical outcomes of 

surgery. The authors compared the rates of retinal detachment (RD) repair and hospitalization for 

endophthalmitis after extracapsular cataract extraction (ECCE) (including phacoemulsification) 

in 1986 and 1987 with those following inpatient cataract extraction in 1984. METHODS: Using 

the 5% random sample of Medicare beneficiaries, we analyzed the claims of all individuals 66 

years of age or older who underwent ECCE by nuclear expression or phacoemulsification in 

1986 and 1987. A total of 57,103 patients were identified and followed to the end of 1988. 

Cumulative probability of RD repair and hospitalization for endophthalmitis was calculated by 

standard lifetable methods. These findings were compared with the cumulative probability of the 

same complications in a cohort of 330,000 patients who underwent cataract extraction on an 

inpatient basis in 1984. RESULTS: In the 1986-to-1987 cohort, the cumulative probability of RD 

within 3 years after cataract surgery was 0.81% and the cumulative probability of 

endophthalmitis within 1 year was 0.08%. The rate of RD is similar to that which we previously 

reported for 330,000 patients who underwent inpatient surgery in 1984, but the rate of 

endophthalmitis is significantly lower in the 1986-to-1987 outpatient cohort (0.08% versus 

0.12%; z = 2.42; P = 0.01). CONCLUSIONS: The shift to outpatient cataract surgery was 

accompanied by no significant increase in the probability of RD repair and possibly a significant 

decrease in the rate of hospitalization for endophthalmitis. 
107

Javitt, J. C., J. M. Tielsch, et al. (1992). “National outcomes of cataract extraction. Increased risk 

of retinal complications associated with Nd:YAG laser capsulotomy. The Cataract Patient 

Outcomes Research Team.” Ophthalmology 99(10): 1487-97; discussion 1497-8. 

 PURPOSE: The authors studied 57,103 randomly selected Medicare beneficiaries who 

underwent extracapsular cataract extraction in 1986 or 1987 to determine the possible association 

between performance of neodymium (Nd):YAG laser capsulotomy and the risk of subsequent 

retinal break or detachment. METHODS: Cases of cataract surgery were identified from 

Medicare claims submitted in 1986 and 1987 and were followed through the end of 1988. 

Episodes of cataract surgery, posterior capsulotomy, and retinal complications were ascertained 

based on procedure and diagnosis codes listed in physician bills and hospital discharge records. 

Lifetable and Cox's proportional hazards models were used to analyze the risk of retinal 

detachment or break in patients undergoing and not undergoing capsulotomy during the period of 

observation. RESULTS: Of the 57,103 persons identified as having undergone extracapsular 

cataract extraction in 1986 or 1987, 13,709 subsequently underwent Nd:YAG laser capsulotomy 

between 1986 and 1988. A total of 337 persons had aphakic or pseudophakic retinal detachments 

between 1986 and 1988 and an additional 194 underwent repair of a retinal break. Proportional 

hazards modeling shows a 3.9-fold increase in the risk of retinal break or detachment among 

those who underwent capsulotomy (95% confidence interval: 2.89 to 5.25). Younger patient age, 

male sex, and white race also were associated with increased risk of retinal complications after 

extracapsular cataract extraction. CONCLUSION: The authors conclude that there is a 

statistically significant increase in the risk of retinal detachment or break in those patients who 

undergo capsulotomy after cataract extraction. Therefore, capsulotomy should be deferred until 

the patient's impairment caused by capsular opacification warrants the increased risk of retinal 

complications associated with performance of capsulotomy. 
108

Katz, J., M. A. Feldman, et al. (2001). “Adverse intraoperative medical events and their 

association with anesthesia management strategies in cataract surgery.” Ophthalmology 108(10): 

1721-6. 

 OBJECTIVE: To compare adverse medical events by different anesthesia strategies for 

cataract surgery. DESIGN: Prospective cohort study. PARTICIPANTS: Patients 50 years of age 

and older undergoing 19,250 cataract surgeries at nine centers in the United States and Canada 

between June 1995 and June 1997. INTERVENTION: Local anesthesia applied topically or by 

injection, with or without oral and intravenous sedatives, opioid analgesia, hypnotics, and 

diphenhydramine (Benadryl). MAIN OUTCOME MEASURES: Intraoperative and postoperative 

adverse medical events. RESULTS: Twenty-six percent of surgeries were performed with topical 

anesthesia and the remainder with injection anesthesia. There was no increase in deaths and 

hospitalizations associated with any specific anesthesia strategy. No statistically significant 

difference was observed in the prevalence of intraoperative events between topical and injection 

anesthesia without intravenous sedatives (0.13% and 0.78%, respectively). The use of 

intravenous sedatives was associated with a significant increase in adverse events for topical 

(1.20%) and injection anesthesia (1.18%), relative to topical anesthesia without intravenous 

sedation. The use of short-acting hypnotic agents with injection anesthesia was also associated 

with a significant increase in adverse events when used alone (1.40%) or in combination with 

opiates (1.75%), sedatives (2.65%), and with the combination of opiates and sedatives (4.04%). 

These differences remained after adjusting for age, gender, duration of surgery, and American 

Society of Anesthesiologists risk class. CONCLUSIONS: Adjuvant intravenous anesthetic 

agents used to decrease pain and alleviate anxiety are associated with increases in medical 

events. However, cataract surgery is a safe procedure with a low absolute risk of medical 

complications with either topical or injection anesthesia. Clinicians should weigh the risks and 

benefits of their use for individual patients. 

Kollarits, C. R., S. Jaweed, et al. (1998). “Comparison of pain, motility, and preoperative 

sedation in cataract phacoemulsification patients receiving peribulbar or sub-Tenon's anesthesia.” 

Ophthalmic Surg Lasers 29(6): 462-5. 

 BACKGROUND AND OBJECTIVES: The authors hoped to reduce the need for 

preoperative sedation and intravenous pain medication during cataract surgery by converting 

from peribulbar anesthesia to sub-Tenon's anesthesia. PATIENTS AND METHODS: A 

consecutive series of 2453 cataract patients' charts were reviewed. Each patient had previously 

watched a videotape explaining the anesthetic method to be used. Requests for preoperative 

sedation were compared between patients who received peribulbar or sub-Tenon's anesthesia. A 

sample of 200 charts of nonsedated patients were reviewed to compare intraoperative pain and 

motility. RESULTS: Intraoperative freedom from pain was reported by 91% of the peribulbar 

patients and 99% of the sub-Tenon's patients. Preoperative sedation was reduced from 26% of 

the peribulbar patients to 6.7% of the sub-Tenon's patients. CONCLUSIONS: Sub-Tenon's 

anesthesia provided excellent intraoperative pain relief and reduced the need for preoperative 

sedation, making it a satisfactory anesthetic technique for patients undergoing cataract 

phacoemulsification in an ambulatory surgery facility. 
109

Mayer, A. S. and R. E. O'Connor (1993). “Respiratory arrest after local anesthesia for outpatient 

cataract surgery: a dramatic but transient complication.” Ann Emerg Med 22(8): 1357-9. 

 Retrobulbar injection of anesthetic agents is common practice before ophthalmologic 

procedures. Rare but life-threatening complications of this procedure include respiratory 

depression and coma. We present the case of a woman with complete respiratory arrest and 

unresponsiveness who was brought into our emergency department from a local freestanding 

surgical center after preoperative retrobulbar anesthetic injection. Subsequently, the 

pathogenesis, clinical features, and supportive treatment for this dramatic but transient 

complication are discussed. 

Rosenfeld, S. I., S. M. Litinsky, et al. (1999). “Effectiveness of monitored anesthesia care in 

cataract surgery.” Ophthalmology 106(7): 1256-60; discussion 1261. 

 OBJECTIVE: To determine the need for monitored anesthesia care in cataract surgery by 

evaluating the incidence of intervention by anesthesia personnel and by looking for associated 

risk factors. DESIGN: Nonrandomized, prospective case series with analysis of consecutive 

cataract surgery cases. PARTICIPANTS: A total of 1006 consecutive cataract surgery patients at 

an ambulatory surgery center over a 6-month period. METHODS: Routine cataract surgery was 

performed with the patient under local anesthesia. A detailed questionnaire was completed by the 

anesthesia personnel at the conclusion of each phase (before, during, and after) of cataract 

surgery. MAIN OUTCOME MEASURES: Age, medical history, and preoperative 

electrocardiogram (EKG) were analyzed as predictors for intervention by anesthesia personnel. 

The nature of the patient's problem and the type of intervention by anesthesia personnel were 

recorded. RESULTS: In 1006 consecutive cataract surgery cases, intervention by anesthesia 

personnel was required in 376 (37.4%) cases. No preoperative identifying characteristics were 

found to be reliable predictors of the need for intervention. There were no statistically significant 

differences in preoperative EKG and some medical conditions such as heart disease, diabetes, 

and thyroid disease between patients who received intervention and those who did not. Certain 

subgroups of patients did show a statistically significantly greater incidence of intervention, 

including systemic hypertensives (41.4%) versus nonhypertensives (34.5%) (P = 0.030), patients 

with pulmonary disease (49.3%) versus no pulmonary disease (36.5%) (P = 0.043), patients with 

renal disease (68.8%) versus no renal disease (36.9%) (P = 0.019), and patients with cancer 

(61.9%) versus no cancer (36.3%) (P = 0.001). Intervention was also required in 61.1 % of 

patients younger than 60 years of age compared to 36.5% of those patients 60 years of age and 

older (P = 0.005). CONCLUSIONS: Because intervention is required in more than one third of 

cataract surgery cases and the authors cannot reliably predict those patients at risk, monitored 

anesthesia care seems justified in cataract surgery with the patient under local anesthesia. 
110

Shammas, H. J. (1996). “Anterior intraocular lens dislocation after combined cataract extraction 

trabeculectomy.” J Cataract Refract Surg 22(3): 358-61. 

 PURPOSE: To evaluate the incidence, cause, and effect of intraocular lens (IOL) 

dislocation after combined cataract extraction and trabeculectomy. SETTING: An ophthalmic 

ambulatory surgery center in Lynwood, California. METHODS: This retrospective study 

comprised 150 patients with open-angle glaucoma who had either planned extracapsular cataract 

extraction (ECCE) (n = 96) or phacoemulsification (n = 54) combined with IOL implantation 

and trabeculectomy. I reviewed type of cataract extraction, preoperative glaucoma medications, 

axial length, and amount of filtration achieved postoperatively. RESULTS: The lens dislocated 

in 20 eyes (13.3%), with the highest incidence after planned ECCE (18.7%) and the lowest after 

phacoemulsification with capsulorhexis (3.7%). Eighteen of 30 eyes (60%) that had excessive 

filtration also had IOL dislocation. Mean induced postoperative myopia in eyes with lens 

dislocation was-2.25 diopters (D) +/- 0.55 (SD). CONCLUSIONS: Anterior IOL dislocation was 

related to increased postoperative filtration and was more common after planned ECCE. In all 

cases, it caused a distorted pupil, posterior synechias, and induced myopia of over -1.00 D. 
111

APPENDIX B.2 

ANNOTATED BIBLIOGRAPHY FOR SELECTED CRANIAL AND SPINAL (MR) 

IMAGING ARTICLES 

Carvlin, M. J., D. N. De Simone, et al. (1992). “Phase II clinical trial of gadoteridol injection, a 

low-osmolal magnetic resonance imaging contrast agent.” Invest Radiol 27 Suppl 1: S16-21. 

 RATIONALE AND OBJECTIVES. The safety and efficacy of a new, low-osmolal 

magnetic resonance imaging contrast medium, gadoteridol injection, were evaluated in a phase 

II, open-label study at doses ranging from 0.05 to 0.30 mmol/kg. METHODS. Eighty-six patients 

with a diagnosis of intracranial tumor received gadoteridol injection followed by magnetic 

resonance imaging. RESULTS. Two adverse events (headache, taste disturbance) in 2 of 86 

(2.3%) patients were reported. Both were of mild intensity and resolved without treatment and 

without residual effects. In 4 of 86 (4.7%) patients, 5 laboratory changes were reported by the 

investigators as possibly related to gadoteridol injection. Efficacy evaluation was conducted in 

80 of the 86 patients who received gadoteridol injection. In these patients, a total of 119 lesions 

was identified, and each was evaluated at four time points after contrast administration, yielding 

a total of 476 lesion studies. Marked enhancement was demonstrated in 402 of 476 (84%) 

lesions, whereas slight enhancement was demonstrated in 62 of 476 (13%) lesions. The 

difference in both the incidence and degree of enhancement of pathology between the predose 

and postdose images was highly significant (P less than .001). CONCLUSIONS. Overall, 

enhanced images provided more diagnostic information and facilitated detection of more lesions 

than precontrast images. Gadoteridol injection at doses up to 0.3 mmol/kg is a safe and effective 

magnetic resonance imaging contrast agent for use in patients with intracranial tumors. 

Grossman, R., M. J. Kuhn, et al. (1998). “Multicenter evaluation of the safety, tolerance, and 

efficacy of OptiMARK in magnetic resonance imaging of the brain and spine.” Acad Radiol 5 

Suppl 1: S154-5; discussion S156. 

 NO ABSTRACT WAS AVAILABLE. 

 

Grossman, R. I., D. L. Rubin, et al. (2000). “Magnetic resonance imaging in patients with central 

nervous system pathology: a comparison of OptiMARK (Gd-DTPA-BMEA) and Magnevist 

(Gd-DTPA).” Invest Radiol 35(7): 412-9. 

 RATIONALE AND OBJECTIVES: The objective of the two pivotal phase 3 studies was 

to evaluate the safety and efficacy of OptiMARK (Gd-DTPA-bis(methoxyethylamide) [GdDTPA-BMEA]) compared with Magnevist (Gd-DTPA) in magnetic resonance imaging of the 

central nervous system. METHODS: Two multicenter, randomized, double-blind, parallel group 

studies were conducted in 395 patients with known or suspected central nervous system 

pathology. Subjects were randomized to receive a single 0.1 mmol/kg intravenous injection of 

either Gd-DTPA-BMEA or Gd-DTPA. The safety of Gd-DTPA-BMEA and Gd-DTPA was 

monitored for up to 72 hours after study drug administration. Precontrast and postcontrast 

administration magnetic resonance scans were acquired using identical imaging planes and 

techniques. RESULTS: No deaths or unexpected adverse events were reported in either group. A 

comparison of adverse events by intensity and relation demonstrated no statistically significant 

differences between the two groups. Gd-DTPA-BMEA and Gd-DTPA were equivalent with 

respect to confidence in diagnosis, conspicuity, and border delineation. CONCLUSIONS: Gd-
112

DTPA-BMEA and Gd-DTPA demonstrated comparable efficacy profiles, and the safety profiles 

were considered similar. 

Murphy, K. P., K. T. Szopinski, et al. (1999). “Occurrence of adverse reactions to gadoliniumbased contrast material and management of patients at increased risk: a survey of the American 

Society of Neuroradiology Fellowship Directors.” Acad Radiol 6(11): 656-64. 

 RATIONALE AND OBJECTIVES: The authors attempted to determine the frequency 

and severity of adverse reactions to gadolinium-based magnetic resonance (MR) contrast agents 

and to identify strategies for management of patients at increased risk. MATERIALS AND 

METHODS: American Society of Neuroradiology program directors were surveyed about 

adverse reactions at their institutions to gadolinium-based contrast agents, the contrast agents 

responsible, and the management of patients with allergy-like reactions to iodinated or 

gadolinium-based agents who required MR contrast agent administration. RESULTS: Fifty-three 

(50.5%) surveys were received from 105 centers. Of 687,255 gadopentetate dimeglumine 

injections, 314 (0.046%) nonallergic reactions and 107 (0.016%) mild, 28 (0.004%) moderate, 

and five (0.001%) severe allergy-like reactions occurred. Of 74,275 gadodiamide injections, 11 

(0.015%) nonallergic and 12 (0.016%) mild allergy-like reactions occurred. Of 64,005 

gadoteridol administrations, 171 (0.267%) nonallergic reactions and 49 (0.077%) mild, 29 

(0.047%) moderate, and 11 (0.017%) severe allergy-like reactions occurred. Twenty-six 

departments took no precautions for patients with previous allergy-like reactions to iodinated 

contrast material. Nineteen did not premedicate patients who previously had reactions to 

gadolinium-based agents before repeat administration of MR contrast agents. CONCLUSION: 

Although MR contrast agents are safe, adverse reactions occur. Many centers have not adopted 

policies for the OFF. 

Nelson, K. L., L. M. Gifford, et al. (1995). “Clinical safety of gadopentetate dimeglumine.” 

Radiology 196(2): 439-43. 

 PURPOSE: To quantify the rate of adverse reactions to gadopentetate dimeglumine. 

MATERIALS AND METHODS: Magnetic resonance (MR) imaging was performed in 15,496 

patients in April-September 1992. Data were collected before and after intravenous 

administration of 0.1 mmol/kg gadopentetate dimeglumine. RESULTS: Adverse reactions 

occurred in 2.4% (n = 372) of patients. Symptoms abated the same or next day in 94.1% (n = 

350). Whereas onset occurred within 30 minutes after injection in 49.7% (n = 185), onset 

occurred more than 1 hour after injection in 44.9% (n = 167). Two serious adverse reactions 

occurred and were attributed to underlying disease. The rate of adverse reaction was 3.7% in 

patients with a history of asthma (31 of 831 patients) or allergy (144 of 3,860 patients). Patients 

with previous reactions to an MR imaging or iodinated contrast agent had an adverse-reaction 

rate in this study of 21.3% (16 of 75) and 6.3% (54 of 857), respectively. The rate of adverse 

reaction was 2.2% when gadopentetate dimeglumine was administered slowly and 2.9% when it 

was administered rapidly. CONCLUSION: Findings confirm the safety of gadopentetate 

dimeglumine. 
113

Olukotun, A. Y., J. R. Parker, et al. (1995). “Safety of gadoteridol injection: U.S. clinical trial 

experience.” J Magn Reson Imaging 5(1): 17-25. 

 As part of the clinical evaluation of gadoteridol injection, intravenous doses ranging from 

0.05 to 0.3 mmol/kg were administered to 1,709 patients and volunteers. Safety monitoring 

included pre- and postdose physical examinations, vital signs, and clinical laboratory values. 

Adverse event recording included occurrence, duration, severity, relationship to injection, and 

clinical importance. No clinically important changes in physical examination results, 

electrocardiograms, or vital signs were attributed to gadoteridol injection except for one case of 

hypotension. Four clinically important changes in laboratory values possibly or definitely related 

to the contrast agent were noted in two patients (0.1%). Adverse events were recorded in 118 

subjects (6.9%), including nausea in 24 subjects (1.4%) and taste perversion in 22 subjects 

(1.3%). All other adverse events occurred with a frequency of less than 1%. Adverse events 

related to contrast agent administration occurred in 79 subjects (4.6%). Gadoteridol injection 

demonstrated excellent clinical safety and patient tolerance at various doses and injection rates. 

Runge, V. M., W. G. Bradley, et al. (1991). “Clinical safety and efficacy of gadoteridol: a study 

in 411 patients with suspected intracranial and spinal disease.” Radiology 181(3): 701-9. 

 In this phase III study, 411 adult patients with suspected intracranial or spinal disease 

underwent magnetic resonance (MR) imaging before and after intravenous injection of 0.1 

mmol/kg gadoteridol (gadolinium 1,4,7-tris [carboxymethyl]-10-[2'-hydroxypropyl]-1,4,7,10-

tetraazacyclododecane+ ++). MR images were evaluated by a single unblinded reader at each of 

27 sites; the diagnosis was confirmed with one of nine imaging or surgical procedures within 8 

weeks before or after MR imaging. After injection, no clinically significant changes were noted 

in laboratory values, physical examination, or vital signs. Adverse clinical events possibly or 

probably associated with injection of gadoteridol were seen in 18 of 411 patients (4.4%); the 

most common were dysgeusia and mild nausea, and all abated without residual effects. MR 

images enhanced with gadoteridol in patients with confirmed disease provided more diagnostic 

information than unenhanced images in 128 of 175 brain examinations (73.1%) and 93 of 137 

spinal examinations (67.9%). A change in diagnosis because of additional information from 

contrast-enhanced images was considered likely in 63 of 214 cranial and 54 of 161 spinal 

studies. 

Runge, V. M. and J. R. Parker (1997). “Worldwide clinical safety assessment of gadoteridol 

injection: an update.” Eur Radiol 7 Suppl 5: 243-5. 

 Gadoteridol injection is a low molecular weight chelate complex of gadolinium (III) 

which is useful as a contrast agent for magnetic resonance imaging. A total of 2481 adult and 

pediatric subjects were studied with gadoteridol at doses from 0.025 to 0.3 mmol/kg in phase IIIIb clinical trials in Europe and the United States. The study population had a mean age of 49 

years, and included 119 patients under 18 years of age and 747 patients over 60 years of age. 

After 2656 administered injections of gadoteridol a total of 233 adverse events were recorded in 

176 exposures, an incidence rate of 6.6 % irrespective of relationship to drug administration. The 

most frequently reported adverse events were nausea (1.5 %), taste perversion (0.9 %), and 

headache (0.6 %). All other adverse events occurred with an incidence of 0.5 % or less. This 

report confirms the excellent safety profile of gadoteridol in healthy subjects and patients with a 

variety of known or suspected pathologies. 
114

Sze, G., M. Brant-Zawadzki, et al. (1993). “Use of the magnetic resonance contrast agent 

gadodiamide in the central nervous system. Results of a multicenter trial.” Invest Radiol 28 

Suppl 1: S49-55. 

 To investigate the safety and efficacy of the low-osmolar, nonionic contrast agent, 

gadodiamide injection (Omniscan, Sanofi Winthrop Pharmaceuticals, New York, NY), for 

magnetic resonance imaging (MRI) of the head and spine, a multicenter study involving 439 

patients was done at 15 centers as part of a Phase II/III clinical trial. Unenhanced MRI scans 

were obtained after which the patients were injected with 0.1 mmol/kg gadodiamide, and the 

MRI was repeated. The patients' vital signs were monitored, and laboratory studies were 

conducted. Neurologic status was examined before and after the study. The images were 

evaluated for contrast enhancement. No patient had any significant adverse event or serious 

change in clinical status. Abnormalities were found in 80% (351) of all patients studied, and it 

was found that, in 75% (266) of these, the postgadodiamide injection images were improved or 

facilitated visualization of lesions compared with preinjection images. The investigators believe 

that, based on the results of this study, gadodiamide injection is safe and effective for imaging 

the head and spine. They suggest that future studies further assess and compare the safety 

parameters of gadodiamide injection with those of other nonionic and ionic gadolinium ligands. 

Yuh, W. T., J. D. Engelken, et al. (1992). “Experience with high-dose gadolinium MR imaging 

in the evaluation of brain metastases.” AJNR Am J Neuroradiol 13(1): 335-45. 

 PURPOSE: To assess the effectiveness and safety of higher doses of gadoteridol in the 

MR evaluation of patients with brain metastases. MATERIALS AND METHODS: Thirty-one 

patients with a clinical suspicion of brain metastases were studied prospectively with 

gadoteridol, a new, nonionic, low-osmolality contrast agent. Each patient received an initial 

injection of 0.1 mmol/kg and an additional dose of 0.2 mmol/kg 30 minutes later. Images were 

obtained before, immediately after, and 10 and 20 minutes after the initial dose. Images also 

were acquired immediately after the additional dose of gadoteridol. RESULTS: No adverse 

effects were attributed to the injection of gadoteridol. Four patients' examinations were excluded 

from analysis because of machine malfunction (two patients) and excessive motion artifact (two 

patients). Four patients had no detectable metastases. After the additional dose of gadoteridol, 

there was a marked qualitative improvement in lesion conspicuity and detection. The conspicuity 

of 80 of 81 lesions was increased in the high-dose studies, and 46 new lesions were detected in 

19 of 27 patients. Quantitative image analysis demonstrated a significant increase in normalized 

mean lesion contrast between the initial-dose and high-dose studies (35 lesions identified in 13 

patients, P less than .0001). The additional information gained by high-dose examinations 

contributed to a potential modification of the treatment in 10 of 27 patients. High-dose 

examinations increased flow-related artifact in the posterior fossa in 12 of 27 patients. 

CONCLUSION: Based on our preliminary results, high-dose gadolinium-enhanced MR 

examinations may have advantages over 0.1 mmol/kg examinations in detecting early and/or 

small metastases. This may be significant in the management of patients with cerebral 

metastases. 
115

Yuh, W. T., D. J. Fisher, et al. (1994). “Phase III multicenter trial of high-dose gadoteridol in 

MR evaluation of brain metastases.” AJNR Am J Neuroradiol 15(6): 1037-51. 

 PURPOSE: To assess the efficacy and safety profile of high-dose (0.3 mmol/kg 

cumulative dose) gadoteridol in patients with suspected central nervous system metastatic 

disease. METHODS: We studied 67 patients using an incremental-dose technique. Patient 

monitoring included a medical history, physical examination, vital signs, and extensive 

laboratory tests within 24 hours before and after the MR examination. Precontrast T1- and T2-

weighted spin-echo studies were performed, followed by intravenous injection of 0.1 mmol/kg of 

gadoteridol. T1-weighted images were acquired immediately after and at 10 and 20 minutes after 

injection. At 30 minutes an additional 0.2 mmol/kg of gadoteridol was administered (0.3-

mmol/kg cumulative dose), and T1-weighted images were acquired. Cases demonstrating 

abnormal MR findings were assessed for efficacy by unblinded and blinded reviewers and were 

analyzed quantitatively. RESULTS: Three adverse effects in two patients were considered to be 

related to gadoteridol administration. No adverse effects were serious; all self-resolved. Fortynine cases showed abnormal MR findings and were included in the efficacy analysis. A 

significantly greater number of lesions was seen on the high-dose as opposed to the standarddose images. Blinded and unblinded readers identified 5 and 8 patients, respectively, with 

solitary lesions on standard-dose examination and multiple lesions on high-dose examination. 

Two patients who had normal standard-dose findings had lesions identified on high-dose studies. 

Quantitative analysis of 133 lesions in 45 patients demonstrated significant increases in lesion 

signal intensity on high-dose studies when compared with standard-dose studies. 

CONCLUSION: Gadoteridol can be safely administered up to a cumulative dose of 0.3 

mmol/kg. High-dose contrast studies provide improved lesion detectability and additional 

diagnostic information over studies performed in the same patients with a 0.1-mmol/kg dose and 

aid in patient diagnosis and treatment. High-dose gadoteridol study may facilitate the care of 

patients with suspected central nervous system metastasis. 
116

Zoarski, G. H., R. B. Lufkin, et al. (1993). “Multicenter trial of gadoteridol, a nonionic 

gadolinium chelate, in patients with suspected head and neck pathology.” AJNR Am J 

Neuroradiol 14(4): 955-61. 

 PURPOSE: To evaluate the safety and efficacy of gadoteridol as an MR contrast agent in 

patients with suspected head and neck pathology. METHODS: One hundred thirty-three adult 

patients were studied with MR at 12 clinical trial sites before and after the intravenous 

administration of 0.10 mmol/kg gadoteridol. After enrollment, patients underwent a complete 

physical examination. Patient monitoring included vital signs, laboratory tests, and recording of 

the incidence and duration of adverse events. To evaluate efficacy, postcontrast T1-weighted 

images were compared with precontrast T1- and T2-weighted images. Investigators having 

clinical information evaluated 129 studies for efficacy; two readers blinded to clinical 

information subsequently evaluated 122 studies using the same criteria as the investigators. 

RESULTS: Eight patients (6.0%) experienced mild adverse events possibly or probably related 

to contrast administration, all of which resolved without treatment. Two clinically significant 

laboratory abnormalities considered related or possibly related to the administration of 

gadoteridol were reported in two patients. Enhancement of pathology was seen in 82.9% of cases 

evaluated by investigators at the study site and in 78.7% of cases subsequently evaluated by the 

blinded readers. Postcontrast images were judged by investigators to provide additional 

diagnostic information over precontrast images in 68.9% of studies. The additional diagnostic 

information available on postcontrast studies most often consisted of improved visualization of 

pathology and better definition of lesion borders. The use of this information might have 

contributed to a change in patient diagnosis in 18.6% of the cases evaluated by the investigators 

and in 16.4% of the cases reviewed by the blinded readers. CONCLUSIONS: Preliminary results 

show gadoteridol to be a safe and efficacious contrast agent for enhanced MR study of 

extracranial and extraspinal head and neck pathology. 
117

APPENDIX B.3 

ANNOTATED BIBLIOGRAPHY FOR SELECTED COLONOSCOPY ARTICLES 

Anderson, M. L., T. M. Pasha, et al. (2000). “Endoscopic perforation of the colon: lessons from a 

10-year study.” Am J Gastroenterol 95(12): 3418-22. 

 OBJECTIVES: To assess the incidence, clinical features, and management of endoscopic 

colon perforations in a large number of patients at a major medical teaching center. METHODS: 

A retrospective review of medical records of all patients with colon perforations from endoscopy 

over a 10-yr period. RESULTS: A total of 10,486 colonoscopies were performed over a 10-yr 

period. There were 20 (0.19%) perforations and two (0.019%) deaths related to colonoscopy and 

two perforations with no deaths in 49,501 sigmoidoscopies (0.004%). The majority of 

perforations (65%) occurred in the sigmoid colon. The mean age of the patients was 72 yr (range, 

48-87 yr). Multivariate analysis using gender and age showed that female gender was an 

independent predictor of a higher risk of perforation (p < 0.05). Electrocautery injury (36%) and 

mechanical injury (32%) from the tip and shaft of the endoscope were the major causes for 

perforation. Most patients (91%) presented within 48 h of endoscopy. Nine patients (47%) 

required a surgical resection with primary anastomosis; seven (37%) required a simple closure. 

The average hospital length of stay was 7.7 +/- 2.8 days. Although trainee endoscopists were 

involved in only 20% of the colonoscopies performed, eight (40%) perforations occurred while 

the training fellow was involved in the case. However, this increased risk of perforation with a 

training fellow was not statistically significant (p = 0.625). CONCLUSIONS: Colonoscopy can 

result in significant morbidity and carries a small risk of death. Sigmoidoscopy has lower risk. 

The following situations may represent increased risk to colonoscopy patients: unusual difficulty 

in traversing the sigmoid colon; difficult examinations in female patients, and difficult 

examinations performed by trainee physicians. 
118

Bini, E. J., B. Firoozi, et al. (2003). “Systematic evaluation of complications related to 

endoscopy in a training setting: A prospective 30-day outcomes study.” Gastrointest Endosc

57(1): 8-16. 

 BACKGROUND: The 30-day frequency of negative outcomes after outpatient 

endoscopy performed by gastroenterology fellows is unknown. METHODS: Questionnaires 

were mailed to 1000 consecutive patients 30 days after endoscopy to evaluate procedure-related 

negative outcomes (serious and minor adverse events) and patient satisfaction. Serious adverse 

events were defined as follows: oversedation requiring administration of a reversal agent, and 

those that resulted in a physician visit, emergency department visit, admission to the hospital, or 

death. Minor adverse events were defined as all problems other than serious adverse events that 

patients related to their endoscopic procedure. RESULTS: The 30-day frequency of negative 

outcomes in the 869 patients who responded was 14.3%, of which 0.6% were serious and 13.7% 

were minor adverse events. The frequency of negative outcomes was 17.1% for EGD, 15.0% for 

colonoscopy, 24.4% for combined EGD and colonoscopy, and 7.8% for flexible sigmoidoscopy. 

One hundred percent of the serious adverse events were known to us, but only 16.0% of minor 

adverse events (p < 0.001). Multiple logistic regression identified midazolam dose (OR for each 

1 mg increase in dose 4.5; 95% CI [2.7, 7.3]; p < 0.001), treatment with warfarin (OR 3.0; 95% 

CI [1.4, 6.2]; p = 0.003), comorbid disease (OR 2.1; 95% CI [1.3, 3.4]; p = 0.001), endoscopy 

performed in July or August (OR 2.0; 95% CI [1.1,3.7]; p = 0.02), and age (OR for each 1 year 

increase in age 1.03; 95% CI [1.01, 1.05]; p = 0.01) as independent predictors of negative 

outcomes. There was a significant association between negative outcomes and decreased patient 

satisfaction, and patients who reported negative outcomes were less likely to agree to endoscopy 

in the future. CONCLUSIONS: Serious adverse events were rare after endoscopy performed by 

gastroenterology fellows. Contacting patients 30 days after outpatient endoscopy significantly 

improved the detection of negative outcomes. Although the majority of negative outcomes were 

minor, these adverse events were associated with decreased patient satisfaction. 
119

Clarke, G. A., B. C. Jacobson, et al. (2001). “The indications, utilization and safety of 

gastrointestinal endoscopy in an extremely elderly patient cohort.” Endoscopy 33(7): 580-4. 

 BACKGROUND: In developed nations, increasing proportions of the population now 

reach advanced age. Physicians may be reluctant to refer such patients for non-critical diagnostic 

and therapeutic interventions, on the basis of perceived diminution of tolerance, safety and 

substantive benefits in these patients. We aimed to review the utility and safety of 

gastrointestinal endoscopy in an extremely elderly cohort. METHODS: The study involved 214 

consecutive participants aged 85 years or more, between 1995 and 1997. They were identified 

using a prospective database linked to the endoscopy reporting system. Procedure type, 

indication, use of sedation, complications, and outcomes were evaluated. RESULTS: The 

median age was 87 (85-94, sigma = 2). The female:male ratio was 3:2; 185 had undergone one 

procedure and 29 two or more; and 65% of procedures were performed on an outpatient basis. Of 

the inpatient procedures, 10% of all procedures were performed emergently, predominantly for 

upper gastrointestinal hemorrhage. Midazolam was administered to 129 patients (60%), at a 

median dose of 2 mg (range 1-11); of these, 75 (35%) also received a median dose of 25 microg 

fentanyl (range 12.5-125). Colonoscopy (n = 95) was the most frequently performed procedure, 

followed by esophagogastroduodenoscopy (EGD) (n = 64) and endoscopic retrograde 

cholangiopancreatography (ERCP) (n = 21). There was no procedure-related mortality. The 

incidence of post-ERCP pancreatitis was 5%, colonic perforation 1%, and cardiopulmonary 

complications in sedated patients, 0.6%. The majority underwent procedures which related to 

active management of ongoing medical problems, and procedures were performed for palliative 

indications in only 15 (7%) patients. CONCLUSIONS: Gastrointestinal endoscopy is extremely 

safe and well tolerated in extremely elderly patients. Age alone should not influence decisions 

relating to its utilization. 

Cohen, C. D., C. Keuneke, et al. (2001). “Hyponatraemia as a complication of colonoscopy.” 

Lancet 357(9252): 282-3. 

 NO ABSTRACT WAS AVAILABLE. 

 
120

Cotton, P. B., P. Connor, et al. (2003). “Colonoscopy: practice variation among 69 hospitalbased endoscopists.” Gastrointest Endosc 57(3): 352-7. 

 BACKGROUND: The medical profession, payers, and patients are interested 

increasingly in the quality of endoscopic procedures, including colonoscopy. The American 

Society for Gastrointestinal Endoscopy has recommended "report cards" by which endoscopists 

may keep track of certain key elements of their practice including indications, findings, duration, 

technical end points, complications, and patient satisfaction. METHODS: The GI-Trac 

endoscopy reporting database includes many of the data points recommended by ASGE for 

report cards. Seven hospital centers in North America have been collecting data prospectively for 

varying periods since 1994. These data were aggregated and analyzed by individual endoscopist. 

A total of 69 endoscopists performed 17,868 colonoscopies. RESULTS: Twelve percent of the 

endoscopists reported that more than 20% of procedures they performed were completely 

normal. The average time taken by 27% of endoscopists was more than 40 minutes (without 

trainees involved), and only 55% achieved a cecal intubation rate of over 90%; for 9% the rate 

was less than 80%. Complication rates were too low for individual comparisons. 

CONCLUSION: These data provide an idea of colonoscopy performance by individual 

endoscopists in mainly academic centers. Incorporating all recommended data elements in future 

reporting databases will contribute to meaningful bench marking and to quality improvement 

efforts. 

Galandiuk, S. and P. Ahmad (1998). “Impact of sedation and resident teaching on complications 

of colonoscopy.” Dig Surg 15(1): 60-3. 

 There is controversy regarding the frequency of sedation-related complications of 

colonoscopies and whether these procedures are safely performed by physicians-in-training. We 

retrospectively reviewed the safety of 1,004 consecutive outpatient colonoscopies. No 

perforations occurred. No patients were hospitalized for sedation-related complications. 

Seventeen percent of patients had significant changes in vital signs that lasted less than 5 min. 

These changes were less common in patients receiving </=3 mg midazolam intravenously 

without meperidine (p < 0.005). Complications were slightly more frequent in procedures 

performed by trainees (23%) than by gastroenterologists (12%) and by surgeons (18%) (p = 

0.01). These data support the safety of colonoscopy under intravenous sedation, even when 

performed by trainees. 
121

Gatto, N. M., H. Frucht, et al. (2003). “Risk of perforation after colonoscopy and sigmoidoscopy: 

a population-based study.” J Natl Cancer Inst 95(3): 230-6. 

 BACKGROUND: Although the risk of bowel perforation is often cited as a major factor 

in the choice between colonoscopy and sigmoidoscopy for colorectal screening, good estimates 

of the absolute and relative risks of perforation are lacking. METHODS: We used a large 

population-based cohort that consisted of a random sample of 5% of Medicare beneficiaries 

living in regions of the United States covered by the Surveillance, Epidemiology, and End 

Results (SEER) Program registries to determine rates of perforation in people aged 65 years and 

older. We identified individuals who were cancer-free and had undergone colonoscopy or 

sigmoidoscopy between 1991 and 1998, calculated both the incidence and risk of perforation 

within 7 days of the procedure, and explored the impact on incidence and risk of perforation of 

age, race/ethnicity, sex, comorbidities, and indication for the procedure. We also estimated the 

risk of death after perforation. Risks were calculated with odds ratios (ORs) and 95% confidence 

intervals (CIs). All statistical tests were two-sided. RESULTS: There were 77 perforations after 

39 286 colonoscopies (incidence = 1.96/1000 procedures) and 31 perforations after 35 298 

sigmoidoscopies (incidence = 0.88/1000 procedures). After adjustment, the OR for perforation 

from colonoscopy relative to perforation from sigmoidoscopy was 1.8 (95% CI = 1.2 to 2.8). 

Risk of perforation from either procedure increased in association with increasing age 

(P(trend)<.001 for both procedures) and the presence of two or more comorbidities 

(P(trend)<.001 for colonoscopy and P(trend) =.03 for sigmoidoscopy). Compared with those 

who were endoscopied and did not have a perforation, the risk of death was statistically 

significantly increased for those who had a perforation after either colonoscopy (OR = 9.0, 95% 

CI = 3.0 to 27.3) or sigmoidoscopy (OR = 8.8, 95% CI = 1.6 to 48.5). The risk of perforation 

after colonoscopy, especially for screening procedures, declined during the 8-year study period. 

CONCLUSIONS: The risk of perforation after colonoscopy is approximately double that after 

sigmoidoscopy, but this difference appears to be decreasing. These observations should be useful 

to clinicians making screening and diagnostic decisions for individual patients and to policy 

officials setting guidelines for colorectal cancer screening programs. 

Godreau, C. J. (1992). “Office-based colonoscopy in a family practice.” Fam Pract Res J 12(3): 

313-20. 

 A total of 112 patients, 64 women and 48 men, underwent 157 in-office colonoscopies 

with intravenous sedation. A total of 113 polyps were found. Thirty polyps were of the 

diminutive (less than 0.6 cm) hyperplastic (metaplastic) or nonneoplastic type. Forty-three were 

of the diminutive adenomatous, or villous, neoplastic type, and 40 were neoplastic but larger 

than 0.6 cm. Biopsies and polypectomies were done. There were no instances of perforation, 

hemorrhage, or other major complications. A spectrum of other colorectal pathology was found, 

the majority of which was treated in the office. Patients were risk stratified for surveillance 

according to polyp histopathology, with nonneoplastic polyps assigned no risk, and neoplastic 

polyps assigned high risk status. This study demonstrates that for the most reliable 

prognostication and risk stratification, all polyps should be removed for histopathological 

assessment. 
122

Hopper, W., K. A. Kyker, et al. (1996). “Colonoscopy by a family physician: a 9-year experience 

of 1048 procedures.” J Fam Pract 43(6): 561-6. 

 BACKGROUND: In the last 15 years, family physicians and general internists have 

adopted flexible fiberoptic endoscopy as a procedure to screen patients at risk of premature death 

from colorectal cancer. There has been controversy regarding the ability of non-fellowshiptrained primary care physicians to extend this experience to full colonoscopy. METHODS: The 

results of 1048 consecutive colonoscopy examinations performed by a family physician over a 9-

year period were tabulated. Outcomes measured included the reach-the-cecum rate (RCR), use of 

medication, complication rate, and diagnostic yield. In a convenience sample of 110 cases, the 

effectiveness of the non-narcotic analgesic ketorolac was assessed by the RCR. Outcomes of 

cases in which ketorolac was used were compared with cases in which traditional sedation and 

analgesia were used. RESULT: A high diagnostic yield without significant complications was 

noted. The RCR for nonmedicated patients was 36%. Among all medicated cases, the RCR was 

93%. In patients who were given the non-narcotic analgesic ketorolac, the RCR was 96%, 

compared with 95% in patients not given ketorolac. CONCLUSIONS: A family physician in 

rural practice was able to attain and sustain a state-of-the-art, reach-the-cecum rate over a 9-year 

period. This service resulted in a high diagnostic yield, high degree of safety, and satisfactory 

results for the community. Ketorolac is an effective alternative for patients who may be 

hypersensitive to narcotic analgesia/sedation. 

Korman, L. Y., B. F. Overholt, et al. (2003). “Perforation during colonoscopy in endoscopic 

ambulatory surgical centers.” Gastrointest Endosc 58(4): 554-7. 

 BACKGROUND: Perforation as a complication of colonoscopy is estimated to occur in 

0.01% to 0.3% of procedures, but the frequency in ambulatory settings is unknown. This study 

determined the number of perforations occurring within a network of endoscopic ambulatory 

surgery centers. METHODS: A total of 116,000 colonoscopies were performed within one 

network of 45 endoscopic ambulatory surgery centers in the United States during 1999. All 

identified perforations were reported to the network clinical director and reviewed by a panel of 

3 gastroenterologists. RESULTS: There were 37 (0.03%) perforations; 27 in women and 10 in 

men. Median patient age was 75 years (range 39-87 years); 18 patients (49%) had diverticular 

disease and 20 (54%) had a history of pelvic or colonic surgery. Twenty-four (65%) procedures 

were diagnostic, and 13 (35%) were therapeutic. The most common site of perforation was the 

sigmoid colon (62%); followed by the ascending colon (16%); cecum, transverse colon, and 

splenic flexure (11%); and rectum, anastomotic, or unknown (11%). The time to diagnosis 

ranged from immediate to 72 hours (29 <1 hour, 8 >1 hour). All patients were hospitalized; 35 

(95%) underwent exploratory laparotomy, and 2 (5%) were treated conservatively. No patient 

died. CONCLUSIONS: Reported perforations for procedures performed in endoscopic 

ambulatory surgery centers occurred most frequently during diagnostic colonoscopy in older 

woman with a history of surgery or diverticular disease. Reported perforations in endoscopic 

ambulatory surgery centers were uncommon. 
123

 Lugay, M., G. Otto, et al. (1996). “Recovery time and safe discharge of endoscopy patients after 

conscious sedation.” Gastroenterol Nurs 19(6): 194-200. 

 The aim of this study was to identify the best method for determining when to safely 

discharge the endoscopy patient; specifically, it was designed to determine whether the patient's 

risk factors, intraoperative occurrences, and/or medications used during endoscopy should be 

used to determine the minimum length of stay postconscious sedation or whether a general 

policy can be used, as is currently practiced at many institutions. Preoperative, intraoperative, 

and postoperative data were collected on a convenience sample of 405 adult ambulatory 

outpatients undergoing upper endoscopy and/or colonoscopy. Subjects were also interviewed by 

phone within 48 hours of discharge to assess postdischarge complications and their duration. Age 

predicted length of time in recovery, but only 2% of the variation in recovery time was predicted 

by the study variables. Intraprocedure occurrences predicted postprocedure occurrence. The 

implications of these and other findings are discussed in relation to nursing practice and future 

research. 

Nelson, D. B., K. R. McQuaid, et al. (2002). “Procedural success and complications of largescale screening colonoscopy.” Gastrointest Endosc 55(3): 307-14. 

 BACKGROUND: Indirect evidence and modeling analyses suggest that colonoscopy 

may be the most cost-effective way to screen the average-risk population for colorectal 

neoplasia. However, the success and safety of primary colonoscopic screening has not been 

prospectively evaluated in a multicenter trial. METHODS: Asymptomatic subjects age 50 to 75 

years who had not undergone examination of the colon within 10 years were recruited from the 

general medicine clinics of 13 Department of Veterans Affairs Medical Centers. Eligible patients 

underwent colonoscopy by study coinvestigators, at which time all polyps were measured, 

photographed, and removed. Patients were contacted at 24 hours and 1 week to track procedurerelated complications. RESULTS: Primary screening colonoscopy was performed in a cohort of 

3196 asymptomatic subjects. A "good" preparation was reported in 81% of patients, and 

colonoscopy to the cecum was successful in 97.2% of cases. Mean insertion time to the cecum 

and total procedure times were 10.5 (8.7) and 30.6 (19.1) minutes, respectively. No 

preprocedural patient characteristics were identified that were predictive of an incomplete 

procedure. At least one polyp was resected in 1672 patients. There was no perforation and no 

death attributed to colonoscopy. Major morbidity considered to be definitely related to 

colonoscopy occurred in 9 of 3196 procedures (0.3%): lower GI bleeding requiring intervention 

(6), myocardial infarction and/or cerebrovascular accident (2), and thrombophlebitis (1). In 

subjects undergoing only diagnostic procedures, the major complication rate was 0.1%. 

CONCLUSIONS: Screening colonoscopy can be performed in multiple centers with a high 

degree of success and safety in large numbers of asymptomatic, average-risk men. 
124

Newcomer, M. K., M. J. Shaw, et al. (1999). “Unplanned work absence following outpatient 

colonoscopy.” J Clin Gastroenterol 29(1): 76-8. 

 The authors investigated the incidence of unplanned work absence the day following 

outpatient colonoscopy and examined factors associated with missing work. A total of 250 

patients were studied. Patient demographic information, the length of the procedure, time of day 

the exam was performed, and the amount and type of sedation medication used was obtained at 

the time of the procedure. The incidence and reasons for missing work were elicited via a phone 

survey 7 days postprocedure. Ten patients (4%) had an unplanned work absence the day after 

their colonoscopy. No complications were noted. Feeling sleepy and weak or abdominal pain and 

bloating were the most common reasons for missing work. In univariate analyses, patients with 

an unplanned work absence were more likely to be younger (p = 0.009), and female (p = 0.02) 

compared with patients who returned to work. No statistically significant differences were found 

with regard to the amount of sedation medication used, the length of the procedure, or whether 

the procedure was performed in the morning or afternoon. Unplanned work absence is low 

following outpatient colonoscopy in a community-based practice. Female gender and younger 

age are associated with a higher likelihood of missing work. Postprocedure work absence may 

have a greater economic impact than procedure-related complications. 

Pierzchajlo, R. P., R. J. Ackermann, et al. (1997). “Colonoscopy performed by a family 

physician. A case series of 751 procedures.” J Fam Pract 44(5): 473-80. 

 BACKGROUND: Colonoscopy, including biopsy and polypectomy, is a procedure not 

commonly performed by primary care physicians. The purpose of this research was to present a 

large case series of colonoscopic procedures performed by a family physician in a rural practice. 

METHODS: A chart review of every colonoscopy procedure performed by a family physician 

over a 7-year period determined the demographic characteristics, indications, findings, and 

complications for each procedure. RESULTS: A total of 751 colonoscopies were performed on 

555 patients (347 women and 208 men), with a mean age of 53.8 years. In 91.5% of procedures, 

the cecum was intubated. The most common indications for colonoscopy were bleeding (49.9%), 

polyp follow-up (20.9%) abdominal pain (11.7%), diarrhea (11.6%), and abnormal findings on 

flexible sigmoidoscopy (8.4%). Three hundred sixteen benign polyps were discovered and 

removed by either biopsy or polypectomy. There were 184 adenomatous colorectal polyps found 

in 134 (17.8%) colonoscopies. Of these 184 adenomatous polyps, 106 (58%) were potentially 

within reach of the flexible sigmoidoscope. Only three adenocarcinomas were discovered during 

the entire study period. There was only one major procedural complication: a patient experienced 

blood oozing from a polypectomy stump; cautery stopped the bleeding, and the patient was 

hospitalized overnight, with no further intervention or transfusion required. There were five other 

self-limited complications, including adverse reactions to sedation and infiltration at the 

intravenous site. CONCLUSIONS: Colonoscopy with polypectomy that was safely and 

competently performed in a solo rural practice adds to the evidence that experienced family 

physicians can provide this important service to their community. 
125

Poser, G. and S. Ladik (1995). “Oxygen saturation post-gastroscopy and post-colonoscopy.” 

Gastroenterology Nursing 18(4): 128-32. 

 A standard of care for providing pulse oximetry monitoring for patients receiving 

conscious sedation during and after endoscopy has not been established. This study sought to 

clarify whether desaturation occurs after gastroscopy and colonoscopy and what characteristics 

are predictive of desaturation that does occur. The convenience sample consisted of 475 adult 

participants receiving meperidine and/or midazolam in a hospital-based outpatient setting. A 

baseline oxygen saturation level was obtained before the procedure. Assessment of the oxygen 

saturation continued in the recovery room for 1 hour, with readings recorded every 10 minutes. 

A saturation of 90% or less was used as the indicator to resume oxygen therapy. Data revealed 

that oxygen desaturation in the recovery phase is influenced by the preprocedure baseline oxygen 

saturation level, smoking history, and age. The incidence of oxygen desaturation was 24% in the 

recovery phase, with the majority of decreases occurring within the first 10 minutes. 

Rex, D. K., T. F. Imperiale, et al. (1999). “Patients willing to try colonoscopy without sedation: 

associated clinical factors and results of a randomized controlled trial.” Gastrointest Endosc

49(5): 554-9. 

 BACKGROUND: Sedation causes most of the complications of colonoscopy. Sedation is 

used selectively in some countries but is routine in the United States. METHODS: Crosssectional survey and randomized controlled trial were used to identify patient factors associated 

with willingness to try colonoscopy without sedation and to compare pain and satisfaction scores 

and willingness to return to the same physician in patients randomized to receive routine sedation 

versus as needed sedation. A single colonoscopist invited 250 consecutive eligible outpatients to 

be randomized to routine sedation versus as needed sedation. Seventeen who preferred no 

sedation and 163 who preferred sedation refused. Seventy accepted and were randomized. 

RESULTS: Male gender (odds ratio 4.33; 95% CI [2.27, 8.26]), increasing age (odds ratio for 

10-year increase 1.28; 95% CI [1.01, 1.06]), and absence of abdominal pain (odds ratio 5.13; 

95% CI [1.68, 15.63]) were associated with willingness to be randomized. Total colonoscopy 

was achieved without sedation in 94% of those who received sedation only as needed. Pain 

scores were higher in the sedation as needed arm. All 35 patients in the routine sedation arm 

were "very satisfied". In the sedation as needed arm, 31 of the 34 were "very satisfied" and 3 

were "somewhat satisfied". All randomized patients said they would return to the same 

colonoscopist. Patients in the sedation as needed arm had less decline in blood pressure, less 

hypoxemia, and lower charges than those in the routine sedation arm. CONCLUSIONS: 

Experienced colonoscopists should consider offering colonoscopy without sedation to selected 

patients. 
126

Rodney, W. M., G. Dabov, et al. (1993a). “Sedation associated with a more complete 

colonoscopy.” J Fam Pract 36(4): 394-400. 

 BACKGROUND. This study examined the effect of sedation on the rate of complete 

colonoscopic examinations by a family physician performing colonoscopy at an urban family 

practice residency. The outcomes of biopsies and polypectomies performed during the period of 

the study were also evaluated. METHODS. Data were prospectively collected on 164 

consecutive colonoscopies. Seventy-three percent (124/164) of the examinations were training 

experiences supervised by the first author. The outcomes of examinations of 126 sedated patients 

were compared with those of 38 nonsedated patients. Patients were not randomly selected. 

RESULTS. Examinations of 126 sedated patients were carried out with an 85% reach-the-cecum 

rate compared with a 31% reach-the-cecum rate for 38 nonsedated patients (P < .05). A higher 

percentage of examinations done without sedation (16%) were terminated because of pain than 

were terminated in sedated patients (5%) (P < .05). An electrolyte purge solution was found to be 

the most effective colonoscopy preparation; only 7% (7/100) of examinations on patients 

prepared by this method were terminated because of inadequate bowel preparation. Adenomas 

were found in 11% (14/126) of sedated patients and in 8% (3/38) of nonsedated patients. Cancer 

was detected in 4 sedated patients. CONCLUSIONS. These findings suggest that sedation in 

colonoscopy is associated with a higher percentage of complete examinations. Also, patients 

prepared with an electrolyte purge solution tend to have fewer examinations terminated because 

of inadequate preparation. 

Rodney, W. M., G. Dabov, et al. (1993b). “Evolving colonoscopy skills in a rural family 

practice: the first 293 cases.” Fam Pract Res J 13(1): 43-52. 

 During the 1980s, many family physicians acquired flexible sigmoidoscopy skills for the 

early detection and secondary prevention of colorectal cancer. As these skills have matured, 

some family physicians have advanced from flexible sigmoidoscopy to the performance of 

colonoscopy. This is a descriptive report of this phenomenon from the private practice of one 

family physician. The first five years of total colonoscopy experience (293 procedures) were 

analyzed. No complications were encountered. A learning effect (measured in terms of scope 

depth and anatomical depth) was present during the first 50 procedures; an improvement in 

examination depth between the 25th and 50th procedure was present. Previous abdominal 

surgery had an effect on limiting scope-insertion depths. There were no complications, and 

among sedated patients, 137/253 (54%) of procedures reached the cecum. Important findings 

included cancer, polyps, and colitis. Twenty-seven percent (9/34) of important pathological 

findings were located beyond the reach of the 60 cm sigmoidoscope. This study of full 

colonoscopy in private family practice suggests it is safe, and the diagnostic yield is substantial. 

Additional studies by family physicians are needed regarding technique, quality assurance, and 

patient satisfaction. 
127

Rosen, L., D. S. Bub, et al. (1993). “Hemorrhage following colonoscopic polypectomy.” Dis 

Colon Rectum 36(12): 1126-31. 

 Clinically significant hemorrhage following colonoscopic polypectomy may occur 

primarily as the polyp is removed or manifest itself days to weeks later secondary to clot 

dissolution. The rate of hemorrhage following colonoscopic polypectomy ranges widely from 0.3 

to 6.1 percent, depending on whether the data are derived from studies using the number of 

patients or number of polypectomies. A retrospective study was performed in our institution to 

study 4,721 patients who underwent polypectomy between January 1987 and December 1991. 

Twenty (0.4 percent) of these patients required hospital admission because of 9 primary and 11 

delayed hemorrhages. Fifty-four polyps were removed from these patients: 11 in the right colon, 

7 in the transverse colon, 17 in the descending colon, and 19 in the sigmoid colon. Eight polyps 

were 2 cm or larger, 10 were pedunculated, and 44 were sessile. Six patients underwent 

cauterization or resnaring of the bleeding polyp site, one patient underwent subtotal colectomy, 

and the remainder of the patients stopped bleeding spontaneously. Factors that could be 

associated with the outcome of hemorrhage include patient age, size, location, number and 

morphology of polyps (i.e., sessile or thick stalk), and use of anticoagulants. An experienced 

endoscopist with knowledge of electrosurgical and technical principles may be the most 

important factor for prevention of postpolypectomy bleeding. 

Shiffman, M. L., M. T. Farrel, et al. (1994). “Risk of bleeding after endoscopic biopsy or 

polypectomy in patients taking aspirin or other NSAIDS.” Gastrointest Endosc 40(4): 458-62. 

 The present study was performed to determine if the risk of bleeding after endoscopic 

biopsy or polypectomy was increased in patients taking aspirin or other nonsteroidal antiinflammatory drugs (NSAIDs). Of 694 patients who underwent either upper gastrointestinal 

endoscopy with biopsy or colonoscopy with biopsy or polypectomy, 320 (46%) had recently 

consumed NSAIDs. Postprocedure bleeding was assessed by both written questionnaire and 

telephone follow-up. A total of 32 patients (4.6%) reported bleeding. Minor, self-limited, 

clinically insignificant bleeding occurred in 20/320 (6.3%) patients taking NSAIDs and 8/374 

(2.1%) control patients (p = .009). Major bleeding requiring hospitalization or treatment occurred 

in only 4 patients (0.58%) (2 from the control group and two from the drug group), each of 

whom had undergone colonic polypectomy. The risk of bleeding increased with polyp size, but 

this did not seem to be affected by NSAID use. We conclude that the risk of significant 

gastrointestinal bleeding after endoscopic biopsy or poly removal is small (< 1%). Although use 

of NSAIDs did increase the incidence of minor self-limited bleeding, an increase in the rate of 

major bleeding was not observed. 
128

Timothy, S. K., T. C. Hicks, et al. (2001). “Colonoscopy in the patient requiring 

anticoagulation.” Dis Colon Rectum 44(12): 1845-8; discussion, 1848-9. 

 PURPOSE: The aim of this study was to assess perioperative warfarin management and 

complications in patients requiring colonoscopy. METHODS: We retrospectively reviewed 109 

cases of colonoscopies performed on 94 patients requiring anticoagulation with warfarin. 

Patients stopped their warfarin three days before colonoscopy. Coagulation profiles obtained just 

before the colonoscopy showed a median prothrombin time of 13.4 seconds with a range of 11.1 

to 29.1 (normal range, 10.9-13) and a median international normalized ratio of 1.2 with a range 

of 0.9 to 2.6. Patients restarted warfarin the day after the examination. RESULTS: During the 

109 colonoscopies, 47 percent of the patients underwent either hot biopsy or snare polypectomy. 

One examination that included several biopsies was associated with a hemorrhagic complication 

(0.92 percent) requiring hospitalization and transfusion. Subset analysis of the therapeutic 

(biopsy and snare polypectomy) group indicated a slightly higher complication rate (1.96 

percent) with a median international normalized ratio of 1.3 (range, 1-2.3) and a median 

prothrombin time of 13.7 (range, 11.6-25.9). CONCLUSION: Patients taking warfarin for 

anticoagulation may safely undergo colonoscopy. The risk of hemorrhagic complications 

increases slightly with hot biopsy or snare procedures. Further studies are needed to refine 

guidelines for colonoscopy in the patient requiring anticoagulation. 

Walker, J. A., R. D. McIntyre, et al. (2003). “Nurse-administered propofol sedation without 

anesthesia specialists in 9152 endoscopic cases in an ambulatory surgery center.” Am J 

Gastroenterol 98(8): 1744-50. 

 Narcotics and benzodiazepines are commonly used for sedation for endoscopy in the 

United States. Propofol has certain advantages over narcotics and benzodiazepines, but its use is 

often controlled by anesthesia specialists. This report describes our experience with dosage, 

safety, patient satisfaction, and discharge time with nurse-administered propofol sedation in 9152 

endoscopic cases.The study was performed in a private practice ambulatory surgery center in 

Medford, Oregon. With the assistance of an anesthesiologist, we developed a protocol for 

administration of propofol in routine endoscopic cases, in which propofol was given by 

registered nurses under the supervision of endoscopists or gastroenterologists. We then applied 

the protocol with 9152 patients.There were seven cases of respiratory compromise (three 

prolonged apnea, three laryngospasm, one aspiration requiring hospitalization), all associated 

with upper endoscopy. Five patients required mask ventilation, but none required endotracheal 

intubation. There were seven colonic perforations (<1 per 1000 colonoscopies), of which three 

may have involved forceful sigmoid disruption. Of patients who had previously received narcotic 

or benzodiazepine sedation, 84% preferred propofol. Gastroenterologists strongly preferred 

propofol. The mean time from completion of procedures to discharge in a sample of 100 patients 

was 18 min.Nurse-administered propofol sedation in an ambulatory surgery center was safe and 

resulted in high levels of patient satisfaction and rapid postprocedure recovery and discharge. 
129

Waye, J. D., B. S. Lewis, et al. (1992). “Colonoscopy: a prospective report of complications.” J 

Clin Gastroenterol 15(4): 347-51. 

 Patients (N = 2,097) undergoing ambulatory office colonoscopy were followed to 

determine the incidence of endoscopic complications. In this group, 1,320 patients had 

diagnostic colonoscopy with or without biopsy; 777 patients had 2,019 polyps removed. Three of 

2,097 patients (0.1%) had transient hypotension requiring i.v. fluid resuscitation and oxygen 

administration. All patients went home without sequelae. Acute postpolypectomy bleeding 

occurred in 11 of 777 patients (1%) requiring acute management; bleeding was controlled during 

colonoscopy in all. Postpolypectomy syndrome occurred in 9 of 777 patients (1%). All patients 

were treated medically. Late postpolypectomy bleeding occurred in 15 of 777 patients (2%). 

Perforation occurred in two of 777 patients (0.3%), at 1 and 9 days postpolypectomy. Both 

patients underwent surgery with uneventful recoveries. We conclude that office colonoscopy 

including polypectomy is safe. The overall complication rate for therapeutic ambulatory 

colonoscopy was 5%, with major events requiring hospitalization in 2% of patients. 

Wexner, S. D., K. A. Forde, et al. (1998). “How well can surgeons perform colonoscopy?” Surg 

Endosc 12(12): 1410-4. 

 BACKGROUND: Little recent data exist relative to the efficacy or postprocedural 

complications of surgeons performing diagnostic or therapeutic colonoscopy. Therefore, the aim 

of this study was to retrospectively assess the outcome of colonoscopy performed by surgeons. 

METHODS: The charts of 2,069 patients who underwent colonoscopy between January 1992 

and April 1995 by one of four surgeons at one of two centers were reviewed. Parameters 

included demographics, indications, procedures and findings, pathology, major complications, 

length of procedures and dosage of medication. RESULTS: 2,069 colonoscopies were performed 

for the following indications: 877 polyp surveillance, 509 cancer surveillance, 287 rectal 

bleeding, 282 family history of colon cancer, 127 change in bowel habits, 112 polyps found by 

flexible sigmoidoscope or barium enema, 92 inflammatory bowel disease, 48 preoperation, and 

58 other indications. Some patients had more than one indication. The cecum could not be 

intubated in 73 cases (3.5%) due to narrowing and stricture [33] redundancy [18], poor 

preparation [14], and other miscellaneous conditions [8]. The average procedure time in the 1, 

023 cases in which it was measured was 34.7 min. Average sedation doses were 2.1 mg of 

midazolam and 75.2 mg of meperedine in these same cases. The 2,069 colonoscopies included 

1,878 biopsies, 353 polypectomies, and 139 other procedures. Some patients had multiple 

therapeutic interventions. Findings included 2,107 polyps, the pathology of which included 907 

tubular; 62 tubulovillous and 41 villous adenomas, 325 hyperplastic polyps, and 68 carcinomas. 

There were five major complications after polypectomies (0.2%) including two cases of bleeding 

and three perforations. The two patients with bleeding were admitted to hospital, one for 

observation for 2 days and the other for colonoscopy, coagulation, and transfusion of 3 units of 

blood. Of the three patients with perforation, one underwent hospitalization for intravenous 

antibiotics and the other two for surgery (0.01%). Surgery included one resection with primary 

closure of the sigmoid perforation and one colostomy. CONCLUSIONS: This study confirms the 

observation that colonoscopy performed by surgeons is safe and rapid whether performed as a 

therapeutic or as a diagnostic procedure. 
130

Zubarik, R., D. E. Fleischer, et al. (1999). “Prospective analysis of complications 30 days after 

outpatient colonoscopy.” Gastrointest Endosc 50(3): 322-8. 

 BACKGROUND: Our objective was to (1) determine whether more complications are 

reported by patients 30 days after outpatient colonoscopy than are discussed at our monthly 

morbidity and mortality conferences, (2) identify complications resulting in visits to the 

emergency department or physician's office or leading to hospitalization, and (3) assess which 

factors put patients at highest risk. A secondary goal was to determine the rate of work lost after 

outpatient colonoscopy. METHODS: Trained interviewers performed standardized telephone 

interviews of consecutive outpatients undergoing colonoscopy at Georgetown University 

Hospital over a 1-year period. RESULTS: One thousand one hundred ninety-six patients were 

contacted 30 days after outpatient colonoscopy and participated in our study. Twenty patients 

had complications that required a visit to an emergency department or physician. Ninety percent 

of these cases (18) were detected at 30 days, but 15% (3) were discussed at morbidity and 

mortality conferences. All seven complications that necessitated hospitalization were identified 

at 30 days, but only two were discussed at our morbidity and mortality conference. The most 

common complications reported by patients were abdominal discomfort (5.4%) and rectal 

bleeding (2.1%). CONCLUSION: More complications are detected by means of contacting 

patients 30 days after outpatient colonoscopy than are discussed at our morbidity and mortality 

conference. 
131

APPENDIX C.1 

SCREENING FORM FOR MedPAC LITERATURE REVIEW 

CATARACTS 

1. Article ID:_______________________ 

1. First Author: ______________________ 

 (Last name of first author) 

2. Reviewer: ________________________ 

4. Procedure: ........................(circle one)

 Phacoemulsification/small incision 

surgery......................................... 1 

 Standard extracapsular cataract 

extraction..................................... 2 

 Other cataract surgery....................3 

 Specify:____________________ 

 Unclear...........................................8 

 None of the above ...............9 (STOP)

5. Study design:....................(circle one)

 Descriptive (historical, letter, etc.)....1 

 Review/ meta-analysis ......................2 

 Randomized clinical trial ...............3 

 Controlled clinical trial ..................4 

 Controlled before/after...................5 

....................................................... 

 Case control ................................... 6 

 Cohort ............................................ 7 

 Case Report/Case series.................8 

 Pop. based cross-sectional ............. 9 

 Other (specify:___________) ......... 10 

6. Study setting:...(check all that apply)

 Inpatient ......................... (STOP) 

 Hospital outpatient dept. .............. 

 Ambulatory surgical center.......... 

 Physician’s office......................... 

 Other (specify:___) (STOP)........... 

 Not specified .................. (STOP) 

7. Provider performing proc.:(check all that 

apply) 

 Opthalmologist............................. 

 Other Surgeon .............................. 

 General Internist........................... 

 Family Medicine .......................... 

 General practitioner ..................... 

 Other subspecialist 

(specify:__________________) ..... 

 Nurse practitioner......................... 

 Physician’s assistant..................... 

 Specialty technician ..................... 

 Other (specify:________________)

 Not specified ................................ 

8. Population chars.:(check all that apply)

 Academic ..................................... 

 Community .................................. 

 Public/Municipal.......................... 

 Managed care............................... 

 Urban............................................ 

 Rural............................................. 

 Other (specify:__________) ........... 

 Not specified ................................ 

9. Reason for procedure: .(check all that 

apply)

 First eye cataract .......................... 

 Second eye cataract ...................... 

 Not specified ................................ 

10. Performed during procedure:(check all that 

apply)

 Other (specify:__________) ........... 

 Not specified ................................ 

11. Study follow-up (maximum days): 

 

 Not specified......................... 
132

12. Sample Size:........................................ 

(If more than one sample, provide 

description to help distinguish samples in 

further review.) 

13. Inclusion/Exclusion Criteria: .............. 

(e.g., age ge 65, etc.) 

Not specified......... 

14. Sample Description:............................ 

Mean age 

N (%) ≥ 65 years 

N (%) Female 

% Minority 

race/ethnicity 

15. Insurance coverage:(check all that apply)

 Medicare ......................................  

 Private Pay ................................... 

 Medicaid ...................................... 

 VA................................................ 

 Not specified ................................ 

 Other (specify:__________) ........... 

 Not specified ................................ 

16. Comorbid conditions: 

(List comorbid conditions of sample; or 

‘none specified’ if none listed.) 

 None specified ............................. 

 Atrial fibrillation .......................... 

 Asthma ......................................... 

 CAD/Angina ................................ 

 Myocardial infarction................... 

 Congestive heart failure ............... 

 Liver Disease/Cirrhosis................ 

 Renal disease................................ 

 HIV/AIDS.................................... 

 COPD........................................... 

 Diabetes Mellitus ......................... 

 Hypertension................................ 

 Stroke ........................................... 

 Cancer .......................................... 

 Cancer Type 

 (specify:________________) 

 Other ...............................................  

 Specify Other: 

 Not specified ................................ 
133

17. Process measures (List process measures and prevalence; e.g., length of procedure, sedation procedures, type 

surgery, contamination of irrigation solutions or lens, etc. – if none specified, state so in first lin

Measure Method of process measure assessment Findings 

 Patient questionnaire........................ Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data.......................... Other (specify:__________)............ Patient questionnaire........................ Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data.......................... Other (specify:__________)............ Patient questionnaire........................ Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data.......................... Other (specify:__________)............
134

18. Outcome measures (List outcome measures and prevalence – if none specified, state so in first line of table.) 

-Posterior capsular opacification -Anterior capsular opacification: -Corneal decompensation (corneal edema, endothelial decompensation, bullous keratopathy, detachment of descem

McLean Syndrome 

-Retained lens material in vitreous: (intraocular inflammation leading to corneal decomensation, glaugoma, uveitis

macular edema 

-Infectious postoperative endophthalmitis: -Retinal detachment: risk factors-history of posterior capsulotomy, vitreous loss, severe myopia, lattice degeneratio

-Macular edema -Astigmatism: risk factors (incision location, size, configuration) -Wound dehiscence -Intraocular lens malposition 

Complications non-related to eye: 

A) associated with general anesthesia 

-arrhythmia -myocardial infarction -hypo- or hypertension -aspiration, pneumonia -nausea, vomiting -confusion 

B) associated with local anesthesia excluding topical (retrobulbar, sub-Tenon's infusion, and peribulbar injections +/- fa

-retrobulbar hemorrhage -globe perforation -strabismus -confusion -respiratory arrest -ptosis 
135

Measure Method of outcome measure assessment Findings 

 Patient questionnaire........................ Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data.......................... Other (specify:__________)............ Patient questionnaire........................ Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data.......................... Other (specify:__________)............ Patient questionnaire........................ Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data.......................... Other (specify:__________)............
136
137

APPENDIX C.2 

SCREENING FORM FOR MedPAC LITERATURE REVIEW 

CRANIAL AND SPINAL MAGNETIC RESONANCE (MR) IMAGING 

1. Article ID:________________________ 

2. First Author:_______________________ 

 (Last name of first author) 

3. Reviewer:_________________________ 

4. Procedure: ....... (circle all that apply)

 MRI Brain/Head without contrast.....1 

 MRI Brain/Head w/contrast 

(non spec)....................................2 

 Endoderm/Ferridex/Ferumoxides 

/AM125....................................... 3 

 Magnevist/gadoteridol/Prohance ......4 

 Gadobenate/Dotarem ........................5 

 Gadodiamide/Omniscan....................6 

 Gadobutrol/Gadovist......................... 7 

 Gadoversetamide/Optimark ..............8 

 Unclear..............................................9 

 Other ............................................... 11 

 None of the above .............11 (STOP)

5. Study design:....................(circle one)

 Descriptive (historical, letter, etc.)....1 

 Review/ meta-analysis ......................2 

 Randomized clinical trial ...............3 

 Controlled clinical trial ..................4 

 Controlled before/after...................5 

 Case control ................................... 6 

 Cohort ............................................ 7 

 Case Report/Case series.................8 

 Pop. based cross-sectional ............. 9 

 Other (specify:___________) ......... 10 

6. Study setting:..... (check all that apply) 

 Inpatient ......................... (STOP) 

 Hospital outpatient dept. .............. 

 Ambulatory surgical center.......... 

 Physician’s office......................... 

 Other (specify:___) (STOP)........... 

 Not specified .................. (STOP) 

 ....................................................... 

7. Provider performing proc.:(check all that apply) 

 Radiologist....................................

 Neuroradiologist...........................

 General radiologist .......................

 Surgeon.........................................

 General Internist ...........................

 Family Medicine...........................

 General practitioner ......................

 Other subspecialist 

(specify:_______________) ............

 Nurse practitioner .........................

 Physician’s assistant .....................

 Specialty technician......................

 Other (specify:________________)

 Not specified....................................

8. Population chars.:(check all that apply)

 Academic......................................

 Community...................................

 Public/Municipal ..........................

 Managed care................................

 Urban ............................................

 Rural .............................................

 Other(specify:____________).........

 Not specified....................................

9. Reason for procedure:(check all that apply)

 Screening .....................................

 Diagnostic.....................................

 Specify: 

 Acute Stroke .................................

 Chronic weakness/neuro. sx .........

 Tumor/malignancy .......................

 Seizures.........................................

 Dementia/memory loss.................

 Headache ......................................

 Trauma..........................................

 Other:............................................

 (specify: ______________) 

 Not specified.................................

 Treatment.........................................

 Surveillance .....................................
138

10. Performed during procedure: 

(check all that apply)

 Biopsy ............................................. 

 Sedation........................................... 

 Specify agent:____________________ 

 Other (specify:__________) ...........  

 Not specified ................................... 

11.Study follow-up (maximum days): 

Not specified......................... 

12. Sample Size: 

(If more than one sample, provide 

description to help distinguish samples in 

further review.) 

13. Inclusion/Exclusion Criteria: 

(e.g., age ge 65, cancer free, with history 

of metal implant, claustrophobia, etc.) 

Not specified......... 

14. Sample Description: 

Mean age 

N (%) ≥ 65 years 

N (%) Female 

% Minority 

race/ethnicity 

15. Insurance coverage:(check all that apply)

 Medicare....................................... 

 Private Pay....................................

 Medicaid.......................................

 VA ................................................

 Not specified.................................

 Other (specify:__________)............

 Not specified.................................
139

16. Comorbid conditions: 

(List comorbid conditions of sample; or ‘none 

specified’ if none listed.) 

 None specified ............................. 

 Atrial fibrillation .......................... 

 Asthma ......................................... 

 CAD/Angina ................................ 

 Myocardial infarction................... 

 Congestive heart failure ............... 

 Liver Disease/Cirrhosis................ 

 Renal disease................................ 

 HIV/AIDS.................................... 

 COPD........................................... 

 Diabetes Mellitus ......................... 

 Hypertension................................ 

 Stroke ........................................... 

 Cancer .......................................... 

 Cancer Type (specify:________________) 

 Other ...............................................  

 Specify Other: 

 Not specified ................................ 

17. Grade/stage of disease: ....................... 

(List grade/stage of disease of sample; or 

‘none specified’ if none listed.) 

 N/A, None specified..................... 
140

18. Process measures (List process measures and prevalence; e.g., length of procedure, sedation procedures, t

specified, state so in first line of table.) 

Measure Method of process measure assessment Findings 

 Patient questionnaire ....................... Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data ......................... Other (specify:__________) ........... Not specified ..................................... Patient questionnaire ....................... Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data ......................... Other (specify:__________) ........... Not specified ..................................... Patient questionnaire ....................... Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data ......................... Other (specify:__________) ........... Not specified .....................................
141

19. Outcome measures (List outcome measures and prevalence; e.g., mortality, major morbidity, pain (excluding 

bp changes, creatinine/renal function, liver function, headache, dizziness, metallic taste, nausea, vomiting, r

attack/anxiety, skin irritation, bleeding from biopsy, etc. – if none specified, state so in first line 

Measure Method of process measure assessment Findings 

 Patient questionnaire........................ Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data.......................... Other (specify:__________)............ Not specified ..................................... Patient questionnaire........................ Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data.......................... Other (specify:__________)............ Not specified ..................................... Patient questionnaire........................ Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data.......................... Other (specify:__________)............ Not specified .....................................
142
143

APPENDIX C.3 

SCREENING FORM FOR MedPAC LITERATURE REVIEW 

COLONOSCOPY 

1. Article ID:________________________ 

2. First Author:_______________________ 

 (Last name of first author) 

3. Reviewer:_________________________ 

4. Procedure: ..........(circle all that apply) 

 Colonoscopy .................................. 1 

 Sigmoidoscopy...............................2 

 Barium Enema ...............................3 

 Virtual Colonoscopy (CT) ............. 4 

 Other .............................................. 5 

 Unclear...........................................8 

 None of the above ...............9 (STOP)

5. Study design:....................(circle one)

 Descriptive (historical, letter, etc.)....1 

 Review/ meta-analysis ......................2 

 Randomized clinical trial ...............3 

 Controlled clinical trial ..................4 

 Controlled before/after...................5 

 Case control ................................... 6 

 Cohort ............................................ 7 

 Case Report/Case series.................8 

 Pop. based cross-sectional ............. 9 

 Other (specify:___________) ......... 10 

6. Study setting:..... (check all that apply) 

 Inpatient ......................... (STOP) 

 Hospital outpatient dept. .............. 

 Ambulatory surgical center.......... 

 Physician’s office......................... 

 Other (specify:___) (STOP)........... 

 Not specified .................. (STOP) 

7. Provider perf. proc.:(check all that apply) 

 Gastroenterologist.........................

 Surgeon.........................................

 General Internist ...........................

 Family Medicine...........................

 General practitioner......................

 Other subspecialist 

(specify:______________) ..............

 Nurse practitioner .........................

 Physician’s assistant .....................

 Specialty technician......................

 Other (specify:__________)............

 Not specified.................................

8. Population chars.:(check all that apply)

 Academic......................................

 Community...................................

 Public/Municipal ..........................

 Managed care................................

 Urban ............................................

 Rural .............................................

 Other (specify:__________)............

 Not specified.................................

9. Reason for proc.:(check all that apply) 

 Screening Ave.-risk patient ..........

 Screening High-risk patient..........

 Diagnostic evaluation ...................

 hemorrhage................................

 anemia........................................

 abdominal pain ..........................

 diverticulosis..............................

 weight loss.................................

 obstruction .................................

 inflammatory bowel dis.............

 diarrhea......................................

 other:___________________ 

 _____________________ ........ 

 Surgical follow-up........................

 Routine follow-up.........................

 Treatment......................................

 Other (specify:__________)............

 Not specified.................................
144

10. Performed during procedure:(check all that apply)

 Biopsy .......................................... 

 Polyp removal .............................. 

 Other (specify:__________) ........ 

 Not specified ................................ 

11. Study follow-up (maximum days): 

 

 Not specified......................... 

12. Sample Size:........................................ 

(If more than one sample, provide 

description to help distinguish samples in 

further review.) 

13. Inclusion/Exclusion Criteria: .............. 

(e.g., age ge 65, cancer free, with history 

of polyps, etc.) 

Not specified......... 

14. Sample Description: ........................... 

Mean age 

N (%) ≥ 65 years 

N (%) Female 

% Minority 

race/ethnicity 

15. Insurance coverage:(check all that apply)

 Medicare....................................... 

 Private Pay....................................

 Medicaid.......................................

 VA ................................................

 Not specified.................................

 Other (specify:__________)............

 Not specified.................................
145

16. Comorbid conditions: 

(List comorbid conditions of sample; or ‘none 

specified’ if none listed.) 

 None specified ............................. 

 Atrial fibrillation .......................... 

 Asthma ......................................... 

 CAD/Angina ................................ 

 Myocardial infarction................... 

 Congestive heart failure ............... 

 Liver Disease/Cirrhosis................ 

 Renal disease................................ 

 HIV/AIDS.................................... 

 COPD........................................... 

 Diabetes Mellitus ......................... 

 Hypertension................................ 

 Stroke ........................................... 

 Cancer .......................................... 

 Cancer Type (specify:________________) 

 Other ...............................................  

 Specify Other: 

 Not specified ................................ 

17. Medications:...... (check all that apply) 

 Aspirin..........................................  

 Coumadin (warfarin).................... 

 Other (specify:__________) ........ 

 Not specified ................................ 

18. Grade/stage of disease:....................... 

(List grade/stage of disease of sample; or 

‘none specified’ if none listed.) 

 N/A, None specified .....................
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19. Process measures (List process measures and prevalence; e.g., length of procedure, sedation procedur

disinfection of equipment, reached caecum, etc. – if none specified, state so in first line of ta

Measure Method of process measure assessment Findings 

 Patient questionnaire ....................... Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data ......................... Other (specify:__________)............ Patient questionnaire ....................... Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data ......................... Other (specify:__________)............ Patient questionnaire ....................... Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data ......................... Other (specify:__________)............
147

20. Outcome measures (List outcome measures and prevalence; e.g., mortality, major morbidity, bleedi

polypectomy site, perforation, nausea, vomiting, bloating, infection requiring antibiotic therapy, etc. – if 

so in first line of table.) 

Measure Method of outcome measure 

assessment 

Findings 

 Patient questionnaire ....................... Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data ......................... Other (specify:__________)............ Patient questionnaire ....................... Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data ......................... Other (specify:__________)............ Patient questionnaire ....................... Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data ......................... Other (specify:__________)............ Patient questionnaire ....................... Provider questionnaire..................... Med. record/chart abstraction.......... Operative report............................... Administrative data ......................... Other (specify:__________)............