# Table of Contents

# I. Executive Summary
This guideline updates and expands the original Centers for Disease Control and Prevention (CDC) Guideline for Prevention of Catheter-associated Urinary Tract Infections (CAUTI) published in 1981. Several developments necessitated revision of the 1981 guideline, including new research and technological advancements for preventing CAUTI, increasing need to address patients in non-acute care settings and patients requiring long-term urinary catheterization, and greater emphasis on prevention initiatives as well as better defined goals and metrics for outcomes and process measures. In addition to updating the previous guideline, this revised guideline reviews the available evidence on CAUTI prevention for patients requiring chronic indwelling catheters and individuals who can be managed with alternative methods of urinary drainage (e.g., intermittent catheterization). The revised guideline also includes specific recommendations for implementation, performance measurement, and surveillance. Although the general principles of CAUTI prevention have not changed from the previous version, the revised guideline provides clarification and more specific guidance based on a defined, systematic review of the literature through July 2007. For areas where knowledge gaps exist, recommendations for further research are listed. Finally, the revised guideline outlines highpriority recommendations for CAUTI prevention in order to offer guidance for implementation. This document is intended for use by infection prevention staff, healthcare epidemiologists, healthcare administrators, nurses, other healthcare providers, and persons responsible for developing, implementing, and evaluating infection prevention and control programs for healthcare settings across the continuum of care. The guideline can also be used as a resource for societies or organizations that wish to develop more detailed implementation guidance for prevention of CAUTI.
Our goal was to develop a guideline based on a targeted systematic review of the best available evidence, with explicit links between the evidence and recommendations. To accomplish this, we used an adapted GRADE system approach for evaluating quality of evidence and determining strength of recommendations. The methodology, structure, and components of this guideline are approved by HICPAC and will be used for subsequent guidelines issued by HICPAC. A more detailed description of our approach is available in the Methods section.
To evaluate the evidence on preventing CAUTI, we examined data addressing three key questions and related subquestions: Evidence addressing the key questions was used to formulate recommendations, and explicit links between the evidence and recommendations are available in the Evidence Review in the body of the guideline and Evidence Tables and GRADE Tables in the Appendices (). It is important to note that Category I recommendations are all considered strong recommendations and should be equally implemented; it is only the quality of the evidence underlying the recommendation that distinguishes between levels A and B. Category IC recommendations are required by state or federal regulation and may have any level of supporting evidence.
The categorization scheme used in this guideline is presented in Table 1 in the Summary of Recommendations and described further in the Methods section.
The Summary of Recommendations is organized as follows:
1. recommendations for who should receive indwelling urinary catheters (or, for certain populations, alternatives to indwelling catheters);
2. recommendations for catheter insertion; 3. recommendations for catheter maintenance; 4. quality improvement programs to achieve appropriate placement, care, and removal of catheters;
5. administrative infrastructure required; and 6. surveillance strategies.
The Implementation and Audit section includes a prioritization of recommendations (i.e., highpriority recommendations that are essential for every healthcare facility), organized by modules, in order to provide facilities more guidance on implementation of these guidelines. A list of recommended performance measures that can potentially be used for internal reporting purposes is also included.
Areas in need of further research identified during the evidence review are outlined in the Recommendations for Further Research. This section includes guidance for specific methodological approaches that should be used in future studies.
Readers who wish to examine the primary evidence underlying the recommendations are referred to the Evidence Review in the body of the guideline, and the Evidence Tables and GRADE Tables in the Appendices (). The Evidence Review includes narrative summaries of the data presented in the Evidence Tables and GRADE Tables. The Evidence Tables include all study-level data used in the guideline, and the GRADE Tables assess the overall quality of evidence for each question. The Appendices also contain a clearly delineated search strategy that will be used for periodic updates to ensure that the guideline remains a timely resource as new information becomes available.

# II. Summary of Recommendations

# B. Examples of Inappropriate Uses of Indwelling Catheters
- As a substitute for nursing care of the patient or resident with incontinence.
- As a means of obtaining urine for culture or other diagnostic tests when the patient can voluntarily void. - For prolonged postoperative duration without appropriate indications (e.g., structural repair of urethra or contiguous structures, prolonged effect of epidural anaesthesia, etc.).

# II. Proper Techniques for Urinary Catheter Insertion

# III. Implementation and Audit

# Prioritization of Recommendations
In this section, the recommendations considered essential for all healthcare facilities caring for patients requiring urinary catheterization are organized into modules in order to provide more guidance to facilities on implementation of these guidelines. The high-priority recommendations were chosen by a consensus of experts based on strength of recommendation as well as on the likely impact of the strategy in preventing CAUTI. The administrative functions and infrastructure listed above in the summary of recommendations are necessary to accomplish the high priority recommendations and are therefore critical to the success of a prevention program. In addition, quality improvement programs should be implemented as an active approach to accomplishing these recommendations and when process and outcome measure goals are not being met based on internal reporting.

# Priority Recommendations for Appropriate Urinary Catheter Use (Module 1)
- Insert catheters only for appropriate indications (see Table 2), and leave in place only as long as needed. Conduct random audits of selected units and calculate compliance rate:
- Numerator: number of patients on unit with catheters with proper documentation of insertion and removal dates - Denominator: number of patients on the unit with a catheter in place at some point during admission - Standardization factor: 100 (i.e., multiply by 100 so that measure is expressed as a percentage) c) Compliance with documentation of indication for catheter placement: Conduct random audits of selected units and calculate compliance rate

# IV. Recommendations for Further Research
Our literature review revealed that many of the studies addressing strategies to prevent CAUTI were not of sufficient quality to allow firm conclusions regarding the benefit of certain interventions. Future studies of CAUTI prevention should: 1. Be primary analytic research (i.e. systematic reviews, meta-analyses, interventional studies, and observational studies ) 2. Evaluate clinically relevant outcomes (e.g., SUTI, bloodstream infections secondary to CAUTI) 3. Adjust for confounders as needed using multivariable analyses 4. Stratify outcomes by patient populations at risk for CAUTI 5. Ensure adequate statistical power to detect differences
The following is a compilation of recommendations for further research:

# V. Background
Urinary tract infections are the most common type of healthcare-associated infection, accounting for more than 30% of infections reported by acute care hospitals. 19 Virtually all healthcare-associated UTIs are caused by instrumentation of the urinary tract. Catheterassociated urinary tract infection (CAUTI) has been associated with increased morbidity, mortality, hospital cost, and length of stay.  In addition, bacteriuria commonly leads to unnecessary antimicrobial use, and urinary drainage systems are often reservoirs for multidrugresistant bacteria and a source of transmission to other patients. 10,11

# Definitions
An indwelling urinary catheter is a drainage tube that is inserted into the urinary bladder through the urethra, is left in place, and is connected to a closed collection system. Alternative methods of urinary drainage may be employed in some patients. Intermittent ("in-and-out") catheterization involves brief insertion of a catheter into the bladder through the urethra to drain urine at intervals. An external catheter is a urine containment device that fits over or adheres to the genitalia and is attached to a urinary drainage bag. The most commonly used external catheter is a soft flexible sheath that fits over the penis ("condom" catheter). A suprapubic catheter is surgically inserted into the bladder through an incision above the pubis. The limitations and heterogeneity of definitions of CAUTI used in various studies present major challenges in appraising the quality of evidence in the CAUTI literature. Study investigators have used numerous different definitions for CAUTI outcomes, ranging from simple bacteriuria at a range of concentrations to, less commonly, symptomatic infection defined by combinations of bacteriuria and various signs and symptoms. Futhermore, most studies that used CDC/NHSN definitions for CAUTI did not distinguish between SUTI and ASB in their analyses. 30 The heterogeneity of definitions used for CAUTI may reduce the quality of evidence for a given intervention and often precludes meta-analyses.
The clinical significance of ASB in catheterized patients is undefined. Approximately 75% to 90% of patients with ASB do not develop a systemic inflammatory response or other signs or symptoms to suggest infection. 6,31 Monitoring and treatment of ASB is also not an effective prevention measure for SUTI, as most cases of SUTI are not preceded by bacteriuria for more than a day. 25 Treatment of ASB has not been shown to be clinically beneficial and is associated with the selection of antimicrobial-resistant organisms.

# Epidemiology
Between 15% and 25% of hospitalized patients may receive short-term indwelling urinary catheters. 12,13 In many cases, catheters are placed for inappropriate indications, and healthcare providers are often unaware that their patients have catheters, leading to prolonged, unnecessary use.  In acute care hospitals reporting to NHSN in 2006, pooled mean urinary catheter utilization ratios in ICU and non-ICU areas ranged from 0.23-0.91 urinary catheterdays/patient-days. 17 While the numbers of units reporting were small, the highest ratios were in trauma ICUs and the lowest in inpatient medical/surgical wards. The overall prevalence of longterm indwelling urethral catheterization use is unknown. The prevalence of urinary catheter use in residents in long-term care facilities in the United States is on the order of 5%, representing approximately 50,000 residents with catheters at any given time. 18 This number appears to be declining over time, likely because of federally mandated nursing home quality measures. However, the high prevalence of urinary catheters in patients transferred to skilled nursing facilities suggests that acute care hospitals should focus more efforts on removing unnecessary catheters prior to transfer. 18 Reported rates of UTI among patients with urinary catheters vary substantially. National data from NHSN acute care hospitals in 2006 showed a range of pooled mean CAUTI rates of 3.1-7.5 infections per 1000 catheter-days. 17 The highest rates were in burn ICUs, followed by inpatient medical wards and neurosurgical ICUs, although these sites also had the fewest numbers of locations reporting. The lowest rates were in medical/surgical ICUs.
Although morbidity and mortality from CAUTI is considered to be relatively low compared to other HAIs, the high prevalence of urinary catheter use leads to a large cumulative burden of infections with resulting infectious complications and deaths. An estimate of annual incidence of HAIs and mortality in 2002, based on a broad survey of US hospitals, found that urinary tract infections made up the highest number of infections (> 560,000) compared to other HAIs, and attributable deaths from UTI were estimated to be over 13,000 (mortality rate 2.3%). 19 And while fewer than 5% of bacteriuric cases develop bacteremia, 6 CAUTI is the leading cause of secondary nosocomial bloodstream infections; about 17% of hospital-acquired bacteremias are from a urinary source, with an associated mortality of approximately 10%. 20 In the nursing home setting, bacteremias are most commonly caused by UTIs, the majority of which are catheterrelated. 21 An estimated 17% to 69% of CAUTI may be preventable with recommended infection control measures, which means that up to 380,000 infections and 9000 deaths related to CAUTI per year could be prevented. 22

# Pathogenesis and Microbiology
The source of microorganisms causing CAUTI can be endogenous, typically via meatal, rectal, or vaginal colonization, or exogenous, such as via contaminated hands of healthcare personnel or equipment. Microbial pathogens can enter the urinary tract either by the extraluminal route, via migration along the outside of the catheter in the periurethral mucous sheath, or by the intraluminal route, via movement along the internal lumen of the catheter from a contaminated collection bag or catheter-drainage tube junction. The relative contribution of each route in the pathogenesis of CAUTI is not well known. The marked reduction in risk of bacteriuria with the introduction of the sterile, closed urinary drainage system in the1960's 23 suggests the importance of the intraluminal route. However, even with the closed drainage system, bacteriuria inevitably occurs over time either via breaks in the sterile system or via the extraluminal route. 24 The daily risk of bacteriuria with catheterization is 3% to 10%, 25,26 approaching 100% after 30 days, which is considered the delineation between short and longterm catheterization. 27 Formation of biofilms by urinary pathogens on the surface of the catheter and drainage system occurs universally with prolonged duration of catheterization. 28 Over time, the urinary catheter becomes colonized with microorganisms living in a sessile state within the biofilm, rendering them resistant to antimicrobials and host defenses and virtually impossible to eradicate without removing the catheter. The role of bacteria within biofilms in the pathogenesis of CAUTI is unknown and is an area requiring further research. Antimicrobial resistance among urinary pathogens is an ever increasing problem. About a quarter of E. coli isolates and one third of P. aeruginosa isolates from CAUTI cases were fluoroquinolone-resistant. Resistance of gram-negative pathogens to other agents, including third-generation cephalosporins and carbapenems, was also substantial 5 . The proportion of organisms that were multidrug-resistant, defined by non-susceptibility to all agents in 4 classes, was 4% of P. aeruginosa, 9% of K. pneumoniae, and 21% of Acinetobacter baumannii. 29

# VI. Scope and Purpose
This guideline updates and expands the original CDC Guideline for Prevention of CAUTI published in 1981. The revised guideline addresses the prevention of CAUTI for patients in need of either short-or long-term (i.e., > 30 days) urinary catheterization in any type of healthcare facility and evaluates evidence for alternative methods of urinary drainage, including intermittent catheterization, external catheters, and suprapubic catheters. The guideline also includes specific recommendations for implementation, performance measurement, and surveillance. Recommendations for further research are also provided to address the knowledge gaps in CAUTI prevention identified during the literature review.
To evaluate the evidence on preventing CAUTI, we examined data addressing three key questions and related subquestions: This document is intended for use by infection prevention staff, healthcare epidemiologists, healthcare administrators, nurses, other healthcare providers, and persons responsible for developing, implementing, and evaluating infection prevention and control programs for healthcare settings across the continuum of care. The guideline can also be used as a resource for societies or organizations that wish to develop more detailed implementation guidance for prevention of CAUTI.

# VII. Methods
This guideline was based on a targeted systematic review of the best available evidence on CAUTI prevention. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach  to provide explicit links between the available evidence and the resulting recommendations. Our guideline development process is outlined in Figure 1.

# Figure 1. The Guideline Development Process

# Development of Key Questions
We first conducted an electronic search of the National Guideline Clearinghouse (

# Literature Search
Following the development of the key questions, search terms were developed for identifying literature relevant to the key questions. For the purposes of quality assurance, we compared these terms to those used in relevant seminal studies and guidelines. These search terms were then incorporated into search strategies for the relevant electronic databases. Searches were performed in Medline (National Library of Medicine) using the Ovid Platform (Ovid Technologies, Wolters Kluwer, New York, NY), EMBASE (Elsevier BV, Amsterdam, Netherlands), CINAHL (Ebsco Publishing, Ipswich, MA) and Cochrane (Cochrane Collaboration, Oxford, UK) (all databases were searched in July 2007), and the resulting references were imported into a reference manager, where duplicates were resolved. For Cochrane reviews ultimately included in our guideline, we checked for updates in July 2008.
The detailed search strategy used for identifying primary literature and the results of the search can be found in Appendix 1B ().

# Study Selection
Titles and abstracts from references were screened by a single author (C.V.G, R.K.A., or D.A.P.) and the full text articles were retrieved if they were 1. relevant to one or more key questions, 2. primary analytic research, systematic reviews or meta-analyses, and 3. written in English.
Likewise, the full-text articles were screened by a single author (C.V.G. or D.A.P.) using the same criteria, and included studies underwent a second review for inclusion by another author (R.K.A.). Disagreements were resolved by the remaining authors. The results of this process are depicted in Figure 2.

# Data Extraction and Synthesis
Data on the study author, year, design, objective, population, setting, sample size, power, followup, and definitions and results of clinically relevant outcomes were extracted into evidence tables (Appendix 2 ()). Three evidence tables were developed, each of which represented one of our key questions. Studies were extracted into the most relevant evidence table . Then, studies were organized by the common themes that emerged within each evidence table. Data were extracted by one author (R.K.A.) and cross-checked by another (C.V.G.). Disagreements were resolved by the remaining authors. Data and analyses were extracted as originally presented in the included studies. Meta-analyses were performed only where their use was deemed critical to a recommendation, and only in circumstances where multiple studies with sufficiently homogenous populations, interventions, and outcomes could be analyzed. Systematic reviews were included in our review. To avoid duplication of data, we excluded primary studies if they were also included in a systematic review captured by our search. The only exception to this was if the primary study also addressed a relevant question that was outside the scope of the included systematic review. Before exclusion, data from the primary studies that we originally captured were abstracted into the evidence tables and reviewed. We also excluded systematic reviews that analyzed primary studies that were fully captured in a more recent systematic review. The only exception to this was if the older systematic review also addressed a relevant question that was outside the scope of the newer systematic review. To ensure that all relevant studies were captured in the search, the bibliography was vetted by a panel of clinical experts.

# Grading of Evidence
First, the quality of each study was assessed using scales adapted from existing methodology checklists, and scores were recorded in the evidence tables. Appendix 3 () includes the sets of questions we used to assess the quality of each of the major study designs. Next, the quality of the evidence base was assessed using methods adapted from the GRADE Working Group. 32 Briefly, GRADE tables were developed for each of the interventions or questions addressed within the evidence tables. Included in the GRADE tables were the intervention of interest, any outcomes listed in the evidence tables that were judged to be clinically important, the quantity and type of evidence for each outcome, the relevant findings, and the GRADE of evidence for each outcome, as well as an overall GRADE of the evidence base for the given intervention or question. The initial GRADE of evidence for each outcome was deemed high if the evidence base included a randomized controlled trial (RCT) or a systematic review of RCTs, low if the evidence base included only observational studies, or very low if the evidence base consisted only of uncontrolled studies. The initial GRADE could then be modified by eight criteria. 34 Criteria which could decrease the GRADE of an evidence base included quality, consistency, directness, precision, and publication bias. Criteria that could increase the GRADE included a large magnitude of effect, a dose-response gradient, or inclusion of unmeasured confounders that would increase the magnitude of effect (Table 3). GRADE definitions are as follows:
1. High -further research is very unlikely to change confidence in the estimate of effect 2. Moderate -further research is likely to affect confidence in the estimate of effect and may change the estimate 3. Low -further research is very likely to affect confidence in the estimate of effect and is likely to change the estimate 4. Very low -any estimate of effect is very uncertain After determining the GRADE of the evidence base for each outcome of a given intervention or question, we calculated the overall GRADE of the evidence base for that intervention or question. The overall GRADE was based on the lowest GRADE for the outcomes deemed critical to making a recommendation.

# Table 3. Rating the Quality of Evidence Using the GRADE Approach
The format of this section was changed to improve readability and accessibility. The content is unchanged.

# Rating the

# Formulating Recommendations
Narrative evidence summaries were then drafted by the working group using the evidence and GRADE tables. One summary was written for each theme that emerged under each key question. The working group then used the narrative evidence summaries to develop guideline recommendations. Factors determining the strength of a recommendation included 1. the values and preferences used to determine which outcomes were "critical," 2. the harms and benefits that result from weighing the "critical" outcomes, and 3. the overall GRADE of the evidence base for the given intervention or question (Table 4). 33 If weighing the "critical outcomes" for a given intervention or question resulted in a "net benefit" or a "net harm," then a "Category I Recommendation" was formulated to strongly recommend for or against the given intervention respectively. If weighing the "critical outcomes" for a given intervention or question resulted in a "trade off" between benefits and harms, then a "Category II Recommendation" was formulated to recommend that providers or institutions consider the intervention when deemed appropriate. If weighing the "critical outcomes" for a given intervention or question resulted in an "uncertain trade off" between benefits and harms, then a "No Recommendation" was formulated to reflect this uncertainty. No recommendation/ Unresolved issue for which there is low to very low quality evidence with unresolved issue uncertain trade offs between benefits and harms.
Category I recommendations are defined as strong recommendations with the following implications: 1. For patients: Most people in the patient's situation would want the recommended course of action and only a small proportion would not; request discussion if the intervention is not offered. 2. For clinicians: Most patients should receive the recommended course of action. 3. For policymakers: The recommendation may be adopted as a policy.
Category II recommendations are defined as weak recommendations with the following implications:
1. For patients: Most people in the patient's situation would want the recommended course of action, but many would not. 2. For clinicians: Different choices will be appropriate for different patients, and clinicians must help each patient to arrive at a management decision consistent with her or his values and preferences. 3. For policymakers: Policy making will require substantial debate and involvement of many stakeholders.
It should be noted that Category II recommendations are discretionary for the individual institution and are not intended to be enforced.
The wording of each recommendation was carefully selected to reflect the recommendation's strength. In most cases, we used the active voice when writing Category I recommendationsthe strong recommendations. Phrases like "do" or "do not" and verbs without auxiliaries or conditionals were used to convey certainty. We used a more passive voice when writing Category II recommendations -the weak recommendations. Words like "consider" and phrases like "is preferable," "is suggested," "is not suggested," or "is not recommended" were chosen to reflect the lesser certainty of the Category II recommendations. Rather than a simple statement of fact, each recommendation is actionable, describing precisely a proposed action to take.
The category "No recommendation/unresolved issue" was most commonly applied to situations where either 1. the overall quality of the evidence base for a given intervention was low to very low and there was no consensus on the benefit of the intervention or 2. there was no published evidence on outcomes deemed critical to weighing the risks and benefits of a given intervention. If the latter was the case, those critical outcomes will be noted at the end of the relevant evidence summary.
Our evidence-based recommendations were cross-checked with those from guidelines identified in our original systematic search. Recommendations from previous guidelines for topics not directly addressed by our systematic review of the evidence were included in our "Summary of Recommendations" if they were deemed critical to the target users of this guideline. Unlike recommendations informed by our literature search, these recommendations are not linked to a key question. These recommendations were agreed upon by expert consensus and are designated either IB if they represent a strong recommendation based on accepted practices (e.g., aseptic technique) or II if they are a suggestion based on a probable net benefit despite limited evidence.
All recommendations were approved by HICPAC. Recommendations focused only on efficacy, effectiveness, and safety. The optimal use of these guidelines should include a consideration of the costs relevant to the local setting of guideline users.

# Reviewing and Finalizing the Guideline
After a draft of the tables, narrative summaries, and recommendations was completed, the working group shared the draft with the expert panel for in-depth review. While the expert panel was reviewing this draft, the working group completed the remaining sections of the guideline, including the executive summary, background, scope and purpose, methods, summary of recommendations, and recommendations for guideline implementation, audit, and further research. The working group then made revisions to the draft based on feedback from members of the expert panel and presented the entire draft guideline to HICPAC for review. The guideline was then posted on the Federal Register for public comment. After a period of public comment, the guideline was revised accordingly, and the changes were reviewed and voted on by HICPAC. The final guideline was cleared internally by CDC and published and posted on the HICPAC website.

# Updating the Guideline
Future revisions to this guideline will be dictated by new research and technological advancements for preventing CAUTI and will occur at the request of HICPAC.

# VIII. Evidence Review

# Q1. Who should receive urinary catheters?
To answer this question, we focused on three subquestions: A. When is urinary catheterization necessary? B. What are the risk factors for CAUTI? and C. What populations are at highest risk of mortality from urinary catheters?

# Q1A. When is urinary catheterization necessary?
The available data examined five main populations. In all populations, we considered CAUTI outcomes as well as other outcomes we deemed critical to weighing the risks and benefits of catheterization. The evidence for this question consists of 1 systematic review, 37 9 RCTs,  and 12 observational studies.  The findings of the evidence review and the grades for all important outcomes are shown in Evidence Review Table 1A.
For operative patients, low-quality evidence suggested a benefit of avoiding urinary catheterization.  This was based on a decreased risk of bacteriuria/unspecified UTI, no effect on bladder injury, and increased risk of urinary retention in patients without catheters. Urinary retention in patients without catheters was specifically seen following urogenital surgeries. The most common surgeries studied were urogenital, gynecological, laparoscopic, and orthopedic surgeries. Our search did not reveal data on the impact of catheterization on peri-operative hemodynamic management.
For incontinent patients, low-quality evidence suggested a benefit of avoiding urinary catheterization. 45, This was based on a decreased risk of both SUTI and bacteriuria/unspecified UTI in male nursing home residents without urinary catheters compared to those with continuous condom catheters. We found no difference in the risk of UTI between having a condom catheter only at night and having no catheter. Our search did not reveal data on the impact of catheterization on skin breakdown.
For patients with bladder outlet obstruction, very low-quality evidence suggested a benefit of a urethral stent over an indwelling catheter. 53 This was based on a reduced risk of bacteriuria in those receiving a urethral stent. Our search did not reveal data on the impact of catheterization versus stent placement on urinary complications.
For patients with spinal cord injury, very low-quality evidence suggested a benefit of avoiding indwelling urinary catheters. 54,56 This was based on a decreased risk of SUTI and bacteriuria in those without indwelling catheters (including patients managed with spontaneous voiding, clean intermittent catheterization , and external striated sphincterotomy with condom catheter drainage), as well as a lower risk of urinary complications, including hematuria, stones, and urethral injury (fistula, erosion, stricture).
For children with myelomeningocele and neurogenic bladder, very low-quality evidence suggested a benefit of CIC compared to urinary diversion or self voiding. 46,57,58 This was based on a decreased risk of bacteriuria/unspecified UTI in patients receiving CIC compared to urinary diversion, and a lower risk of urinary tract deterioration (defined by febrile urinary tract infection, vesicoureteral reflux, hydronephrosis, or increases in BUN or serum creatinine) compared to self-voiding and in those receiving CIC early ( 3 years of age).

# Evidence Review Table 1A. When is urinary catheterization necessary?
1A.1. Use urinary catheters in operative patients only as necessary, rather than routinely.

# Q1B. What are the risk factors for CAUTI?
To answer this question, we reviewed the quality of evidence for those risk factors examined in more than one study. We considered the critical outcomes for decision-making to be SUTI and bacteriuria. The evidence for this question consists of 11 RCTs 59-69 and 37 observational studies. 9,50,54, The findings of the evidence review and the grades for all important outcomes are shown in Evidence Review Table 1B.
For SUTI, 50,54,61,62,74,75,79,83,102,103

# Q1C. What populations are at highest risk of mortality from urinary catheters?
To answer this question, we reviewed the quality of evidence for those risk factors examined in more than one study. The evidence for this question consists of 2 observational studies. 7,74 The findings of the evidence review and the grades for all important outcomes are shown in Evidence Review Table 1C.
Low-quality evidence suggested that older age, higher severity of illness, and being on an internal medicine service compared to a surgical service were independent risk factors for mortality in patients with indwelling urinary catheters. Both studies evaluating these risk factors found the highest risk of mortality in patients over 70 years of age. Low-quality evidence also suggested that CAUTI was a risk factor for mortality in patients with catheters.
Evidence Review Table 1C. What populations are at highest risk of mortality from catheters?
1C.1. Minimize urinary catheter use and duration in all patients, particularly those who may be at higher risk for mortality due to catheterization, such as the elderly and patients with severe illness. (Category IB)

# Q2. For those who may require urinary catheters, what are the best practices?
To answer this question, we focused on four subquestions: A. What are the risks and benefits associated with different approaches to catheterization? B. What are the risks and benefits associated with different types of catheters or collecting systems? C. What are the risks and benefits associated with different catheter management techniques D. What are the risks and benefits associated with different systems interventions?

# Q2A. What are the risks and benefits associated with different approaches to catheterization?
The available data examined the following comparisons of different catheterization approaches:
1. External versus indwelling urethral 2. Intermittent versus indwelling urethral 3. Intermittent versus suprapubic 4. Suprapubic versus indwelling urethral 5. Clean intermittent versus sterile intermittent For all comparisons, we considered SUTI, bacteriuria/unspecified UTI, or combinations of these outcomes depending on availability, as well as other outcomes critical to weighing the risks and benefits of different catheterization approaches. The evidence for this question consists of 6 systematic reviews, 37, 16 RCTs, 62,63, and 18 observational studies. 54,73,81,84, The findings of the evidence review and the grades for all important outcomes are shown in Evidence Review Table 2A

# Q2A.1. External versus indwelling urethral
Low-quality evidence suggested a benefit of using external catheters over indwelling urethral catheters in male patients who require a urinary collection device but do not have an indication for an indwelling catheter such as urinary retention or bladder outlet obstruction. 81,109,123 This was based on a decreased risk of a composite outcome of SUTI, bacteriuria, or death as well as increased patient satisfaction with condom catheters. Differences were most pronounced in men without dementia. Statistically significant differences were not found or reported for the individual CAUTI outcomes or death. Our search did not reveal data on differences in local complications such as skin maceration or phimosis.

# Q2A.2. Intermittent versus indwelling urethral
Low-quality evidence suggested a benefit of using intermittent catheterization over indwelling urethral catheters in selected populations. 84,135,136 This was based on a decreased risk of SUTI and bacteriuria/unspecified UTI but an increased risk of urinary retention in postoperative patients with intermittent catheterization. In one study, urinary retention and bladder distension were avoided by performing catheterization at regular intervals (every 6-8 hrs) until return of voiding. Studies of patients with neurogenic bladder most consistently found a decreased risk of CAUTI with intermittent catheterization. Studies in operative patients whose catheters were removed within 24 hrs of surgery found no differences in bacteriuria with intermittent vs. indwelling catheterization, while studies where catheters were left in for longer durations had mixed results. Our search did not reveal data on differences in patient satisfaction.

# Q2A.3. Intermittent versus suprapubic
Very low-quality evidence suggested a benefit of intermittent over suprapubic catheterization in selected populations 115,116, based on increased patient acceptability and decreased risk of urinary complications (bladder calculi, vesicoureteral reflux, and upper tract abnormalities). Although we found a decreased risk of bacteriuria/unspecified UTI with suprapubic catheterization, there were no differences in SUTI. The populations studied included women undergoing urogynecologic surgery and spinal cord injury patients.

# Q2A.4. Suprapubic versus indwelling urethral
Low-quality evidence suggested a benefit of suprapubic catheters over indwelling urethral catheters in selected populations. 37,62,104,107,108,135,136 This was based on a decreased risk of bacteriuria/unspecified UTI, recatheterization, and urethral stricture, and increased patient comfort and satisfaction. However, there were no differences in SUTI and an increased risk of longer duration of catheterization with suprapubic catheters. Studies involved primarily postoperative and spinal cord injury patients. Our search did not reveal data on differences in complications related to catheter insertion or the catheter site.

# Q2A.5. Clean intermittent versus sterile intermittent
Moderate-quality evidence suggested no benefit of using sterile over clean technique for intermittent catheterization. 63,73,105, No differences were found in the risk of SUTI or bacteriuria/unspecified UTI. Study populations included nursing home residents and adults and children with neurogenic bladder/spinal cord injury.

# Q2B. What are the risks and benefits associated with different catheters or collecting systems?
The available data examined the following comparisons between different types of catheters and drainage systems:
1. Antimicrobial/antiseptic catheters vs. standard catheters a. Silver-coated catheters vs. standard catheters b. Nitrofurazone-impregnated catheters vs. standard catheters 2. Hydrophilic catheters vs. standard catheters 3. Closed vs. open drainage systems 4. Complex vs. simple drainage systems 5. Preconnected/sealed junction catheters vs. standard catheters 6. Catheter valves vs. catheter bags For all comparisons, we considered CAUTI outcomes as well as other outcomes critical to weighing the risks and benefits of different types of catheters or collecting systems. The evidence for this question consists of 5 systematic reviews, 37, 17 RCTs, 64, 23 observational studies, 82,86,89,97, and 3 economic analyses. 179180,181 The findings of the evidence review and the grades for all important outcomes are shown in Evidence Review Table 2B.

# Q2B.1.a. Silver-coated catheters vs. standard catheters
Low-quality evidence suggested a benefit of silver-coated catheters over standard latex catheters. 37,82,86,137-139,143,159-163, 165,166 This was based on a decreased risk of bacteriuria/unspecified UTI with silver-coated catheters and no evidence of increased urethral irritation or antimicrobial resistance in studies that reported data on microbiological outcomes. Differences were significant for silver alloy-coated catheters but not silver oxide-coated catheters. In a meta-analysis of randomized controlled trials (see Appendix), silver alloy-coated catheters reduced the risk of asymptomatic bacteriuria compared to standard latex catheters (control latex catheters were either uncoated or coated with hydrogel, Teflon, or silicone), whereas there were no differences when compared to standard, all silicone catheters. The effect of silver alloy catheters compared to latex catheters was more pronounced when used in patients catheterized <1 week. The results were robust to inclusion or exclusion of non peerreviewed studies. Only one observational study found a decrease in SUTI with silver alloycoated catheters. 166 The setting was a burn referral center, where the control catheters were latex, and patients in the intervention group had new catheters placed on admission, whereas the control group did not. Recent observational studies in hospitalized patients found mixed results for bacteriuria/unspecified UTI.

# Q2B.1.b. Nitrofurazone-impregnated catheters vs. standard catheters
Low-quality evidence suggested a benefit of nitrofurazone-impregnated catheters in patients catheterized for short periods of time. 137,138 This was based on a decreased risk of bacteriuria and no evidence of increased antimicrobial resistance in studies that reported microbiological outcomes. Differences were significant in a meta-analysis of three studies examining nitrofurazone-impregnated catheters (only one individual study significant) when duration of catheterization was 1 week, although the meta-analysis was borderline significant.

# Q2B.2. Hydrophilic catheters vs. standard catheters
Very low-quality evidence suggested a benefit of hydrophilic catheters over standard nonhydrophilic catheters in specific populations undergoing clean intermittent catheterization. 137,169 This was based on a decreased risk of SUTI, bacteriuria, hematuria, and pain during insertion, and increased patient satisfaction. Differences in CAUTI outcomes were limited to one study of spinal cord injury patients and one study of patients receiving intravesical immunochemoprophylaxis for bladder cancer, while multiple other studies found no significant differences.

# Q2B.3. Closed vs. open drainage systems
Very low-quality evidence suggested a benefit of using a closed rather than open urinary drainage system. 89,171 This was based on a decreased risk of bacteriuria with a closed drainage system. One study also found a suggestion of a decreased risk of SUTI, bacteremia, and UTIrelated mortality associated with closed drainage systems, but differences were not statistically significant. Sterile, continuously closed drainage systems became the standard of care based on an uncontrolled study published in 1966 demonstrating a dramatic reduction in the risk of infection in short-term catheterized patients with the use of a closed system. 23 Recent data also include the finding that disconnection of the drainage system is a risk factor for bacteriuria (Q1B).

# Q2B.4. Complex vs. simple drainage systems
Low-quality evidence suggested no benefit of complex closed urinary drainage systems over simple closed urinary drainage systems. 154,172,176,177 Although there was a decreased risk of bacteriuria with the complex systems, differences were found only in studies published before 1990, and not in more recent studies. The complex drainage systems studied included various mechanisms for reducing bacterial entry, such as antiseptic-releasing cartridges at the drain port of the urine collection bag; see evidence table for systems evaluated.

# Q2B.5. Preconnected/sealed junction catheters vs. standard catheters
Low-quality evidence suggested a benefit of using preconnected catheters with junction seals over catheters with unsealed junctions to reduce the risk of disconnections. 64,153,156,175 This was based on a decreased risk of SUTI and bacteriuria with preconnected sealed catheters. Studies that found differences had higher rates of CAUTI in the control group than studies that did not find an effect.

# Q2B.6. Catheter valves vs. drainage bags
Moderate-quality evidence suggested a benefit of catheter valves over drainage bags in selected patients with indwelling urinary catheters. 140 Catheter valves led to greater patient satisfaction but no differences in bacteriuria/unspecified UTI or pain/bladder spasms. Details regarding the setting for recruitment and follow-up of the patients in the studies were unclear, and the majority of subjects were men. Our search did not reveal data on the effect of catheter valves on bladder function, bladder/urethral trauma, or catheter blockage.

# Q2C. What are the risks and benefits associated with different catheter management techniques?
The available data examined the following catheter management techniques: For all comparisons, we considered CAUTI outcomes as well as other outcomes critical to weighing the risks and benefits of different catheter management techniques. The evidence for this question consists of 6 systematic reviews, 37,105,106, 56 RCTs, 60,61,143,158,158, 34 observational studies, 83,85,88,90,96,102,133,167,178, and 1 economic analysis. 180 The findings of the evidence review and the grades for all important outcomes are shown in Evidence Review Table 2C.

# Q2C.1. Antimicrobial prophylaxis
Low-quality evidence suggested no benefit of antimicrobial prophylaxis in patients undergoing short-term catheterization. 37,60,61,83,85,133,158,178,182,185,186, This was based on heterogeneous results for SUTI and bacteriuria/unspecified UTI and no adverse events related to antimicrobials. Lack of consistency in specific factors, such as patient population, antimicrobial agents, timing of administration, and duration of follow-up, did not allow for a summary of evidence of the effect of antimicrobial prophylaxis on CAUTI in patients undergoing short term catheterization. Only two studies evaluated adverse events related to antimicrobials. Our search did not reveal data on antimicrobial resistance or Clostridium difficile infection.
Low-quality evidence suggested no benefit of antimicrobial prophylaxis in patients undergoing long-term catheterization (indwelling and clean intermittent catheterization). 106,183,192,194,235,238 This was based on a decreased risk of bacteriuria, heterogeneous results for SUTI, and no differences reported for catheter encrustation or adverse events, although data were sparse. One systematic review suggested an increase in antimicrobial resistance with antimicrobial use.

# Q2C.2. Urinary antiseptics
Low-quality evidence suggested a benefit of methenamine for short-term catheterized patients. 196,197 This was based on a reduced risk of SUTI and bacteriuria and no differences in adverse events. Evidence was limited to two studies of patients following gynecological surgery in Norway and Sweden.
Very low-quality evidence suggested a benefit of methanamine for long-term catheterized patients. 106, This was based on a reduced risk of encrustation but no differences in risk of SUTI or bacteriuria. Data on encrustation was limited to one study. Studies involved primarily elderly and spinal cord injury patients with chronic indwelling catheters

# Q2C.3. Bladder irrigation
Low-quality evidence suggested no benefit of bladder irrigation in patients with indwelling or intermittent catheters. 66,69, This was based on no differences in SUTI and heterogeneous findings for bacteriuria.

# Q2C.4. Antiseptic instillation in the drainage bag
Low-quality evidence suggested no benefit of antiseptic instillation in urinary drainage bags. 90, This was based on no differences in SUTI and heterogeneous results for bacteriuria.

# Q2C.5. Periurethral care
Low-quality evidence suggested no benefit of antiseptic meatal cleaning regimens before or during catheterization to prevent CAUTI. 65,67,68,88,158,246,247 This was based on no difference in the risk of bacteriuria in patients receiving periurethral care regimens compared to those not receiving them. One study found a higher risk of bacteriuria with cleaning of the urethral meatus-catheter junction (either twice daily application of povidine-iodine or once daily cleaning with a non-antiseptic solution of green soap and water) in a subgroup of women with positive meatal cultures and in patients not receiving antimicrobials. Periurethral cleaning with chlorhexidine before catheter insertion did not have an effect in two studies.

# Q2C.6. Routine catheter or bag change
Low-quality evidence suggested no benefit of routine catheter or drainage bag changes to prevent CAUTI. 102,248,249 This was based on no difference or an increased risk of SUTI and no difference in bacteriuria with routine compared to as-needed changes or with more frequent changing intervals. One study in nursing home residents found no differences in SUTI with routine monthly catheter changes compared to changing only for obstruction or infection, but the study was underpowered to detect a difference. Another study in home care patients found an increased risk of SUTI when catheters were changed more frequently than monthly.

# Q2C.7. Catheter lubricants
Very low-quality evidence suggested a benefit of using lubricants for catheter insertion. 167, This was based on a decreased risk of SUTI and bacteriuria with the use of a prelubricated catheter compared to a catheter lubricated by the patient and a decreased risk of bacteriuria with use of a lubricant versus no lubricant. Studies were heterogeneous both in the interventions and outcomes studied. Several studies comparing antiseptic lubricants to nonantiseptic lubricants found no significant differences.

# Q2C.8. Securing devices
Low-quality evidence suggested no benefit of using catheter securing devices to prevent CAUTI. 224 This was based on no significant difference in the risk of SUTI or meatal erosion. The only study in this category looked at one particular product.

# Q2C.9. Bacterial interference
Moderate-quality evidence suggested a benefit of using bacterial interference in catheterized patients. 225 In the one study evaluating this intervention, urinary colonization with a nonpathogenic Escherichia coli was associated with a decreased risk of SUTI in adults with spinal cord injury and a history of frequent CAUTI.

# Q2C.10. Catheter cleansing
Very low-quality evidence suggested a benefit of wet versus dry storage procedures for catheters used in clean intermittent catheterization. 255 This was based on a decreased risk of SUTI with a wet storage procedure in one study of spinal cord injury patients undergoing clean intermittent catheterization compared to a dry storage procedure where the catheter was left to air dry after washing. In the wet procedure, the catheter was stored in a dilute povidone-iodine solution after washing with soap and water.

# Q2C.11. Catheter removal strategies a. Clamping vs. free drainage prior to removal
Low-quality evidence suggested no benefit of clamping versus free drainage before catheter removal. 37,184 This was based on no difference in risk of bacteriuria, urinary retention, or recatheterization between the two strategies. One study comparing a clamp and release strategy to free drainage over 72 hours found a greater risk of bacteriuria in the clamping group.

# b. Postoperative duration of catheterization
Moderate-quality evidence suggested a benefit of shorter versus longer postoperative durations of catheterization. 37,184,227,228 This was based on a decreased risk of bacteriuria/unspecified UTI, decreased time to ambulation and length of stay, no differences in urinary retention and SUTI, and increased risk of recatheterization. Significant decreases in bacteriuria/unspecified UTI were found specifically for comparisons of 1 day versus 3 or 5 days of postoperative catheterization. Recatheterization risk was greater in only one study comparing immediate removal to removal 6 or 12 hours after hysterectomy.

# Q2C.12. Assessment of urine volumes
Low-quality evidence suggested a benefit of using portable ultrasound to assess urine volume in patients undergoing intermittent catheterization. 229,230 This was based on fewer catheterizations but no reported differences in risk of unspecified UTI. Patients studied were adults with neurogenic bladder in inpatient rehabilitation centers. Our search did not reveal data on the use of ultrasound in catheterized patients in other settings. We considered CAUTI outcomes, duration of catheterization, recatheterization, and transmission of pathogens when weighing the risks and benefits of different systems interventions. The evidence for this question consists of 1 RCT 259 and 19 observational studies. 3,25, The findings of the evidence review and the grades for all important outcomes are shown in Evidence Review Table 2D.

# Q2D.1. Multifaceted infection control/quality improvement programs
Low-quality evidence suggested a benefit of multifaceted infection control/quality improvement programs to reduce the risk of CAUTI. 3, This was based on a decreased risk of SUTI, bacteriuria/unspecified UTI, and duration of catheter use with implementation of such programs. Studies evaluated various multifaceted interventions. The studies with significant findings included:
1. education and performance feedback regarding compliance with catheter care, emphasizing hand hygiene, and maintaining unobstructed urine flow;
2. computerized alerts to physicians, nurse-driven protocols to remove catheters, and use of handheld bladder scanners to assess for urinary retention;
3. guidelines and education focusing on perioperative catheter management; and 4. a multifaceted infection control program including guidelines for catheter insertion and maintenance. A program using a checklist and algorithm for appropriate catheter use also suggested a decrease in unspecified UTI and catheter duration, but statistical differences were not reported.

# Q2D.2. Reminders
Very low-quality evidence suggested a benefit of using urinary catheter reminders to prevent CAUTI.  This was based on a decreased risk of bacteriuria and duration of catheterization and no differences in recatheterization or SUTI when reminders were used. Reminders to physicians included both computerized and non-computerized alerts about the presence of urinary catheters and the need to remove unnecessary catheters.

# Q2D.3. Bacteriologic monitoring
Very low-quality evidence suggested no benefit of bacteriologic monitoring to prevent CAUTI. 25,271 Although one study found a decreased risk of bacteriuria during a period of bacteriologic monitoring and feedback, only 2% of SUTI episodes were considered potentially preventable with the use of bacteriologic monitoring.

# Q2D.4. Hand hygiene
Very low-quality evidence suggested a benefit of using alcohol hand sanitizer in reducing CAUTI. This was based on one study in a rehabilitation facility that found a decrease in unspecified UTI, although no statistical differences were reported. 272 A separate multifaceted study that included education and performance feedback on compliance with catheter care and hand hygiene showed a decrease in risk of SUTI. 265

# Q2D.5. Patient placement
Very low-quality evidence suggested a benefit of spatially separating patients to prevent transmission of urinary pathogens. 273 This was based on a decreased risk of transmission of urinary bacterial pathogens in nursing home residents in separate rooms compared to residents in the same rooms.

# Q2D.6. Catheter team versus self-catheterization
Very low-quality evidence suggested no benefit of a catheter team to prevent CAUTI among patients requiring intermittent catheterization. 274 This was based on one study showing no difference in unspecified UTI between use of a catheter care team and self-catheterization for intermittent catheterization in paraplegic patients.

# Q2D.7. Feedback
Very low-quality evidence suggested a benefit of using nursing feedback to prevent CAUTI. 275 This was based on a decreased risk of unspecified UTI during an intervention where nursing staff were provided with regular reports of unit-specific rates of CAUTI.

# Q2D.8. Nurse-directed catheter removal
Very low-quality evidence suggested a benefit of a nurse-directed catheter removal program to prevent CAUTI. 276 This was based on a decreased risk of unspecified UTI during an intervention where criteria were developed that allowed a registered nurse to remove a catheter without a physician's order when no longer medically necessary. Of the three intensive care units where the intervention was implemented, differences were significant only in the coronary intensive care unit.
Evidence Review Table 2D

# Q3: What are the best practices for preventing UTI associated with obstructed urinary catheters?
The available data examined the following practices:
1. Methods to prevent/reduce encrustations or blockage 2. Catheter materials preventing blockage For this question, available relevant outcomes included blockage/encrustation. We did not find data on the outcomes of CAUTI. The evidence for this question consists of 1 systematic review, 277 2 RCTs, 278,279 and 2 observational studies. 280,281 The findings of the evidence review and the grades for all important outcomes are shown in Evidence Review Table 3.

# Q3.1. Methods to prevent/reduce encrustations or blockage
Low-quality evidence suggested a benefit of acidifying solutions or oral acetohydroxamic acid in preventing or reducing catheter encrustations and blockage in long-term catheterized patients. 277,278,280,281 No differences were seen with daily catheter irrigation with normal saline.

# Q3.2. Catheter materials preventing blockage
Low-quality evidence suggested a benefit of silicone over latex or Teflon-coated catheters in prevention or reducing catheter encrustations in long-term catheterized patients who were prone to blockage. No differences were seen with different materials in patients considered "nonblockers." 279 Evidence Review Table 3. What are the best practices for preventing UTI associated with obstructed urinary catheters?

# Abbreviations Abbreviation