Ambulatory Surgery in the United States, 1994

by Lola Jean Kozak, Margaret Jean Hall, Robert Pokras, and Linda Lawrence, Division of Health Care Statistics

Highlights

Ambulatory surgery visits

+ In 1994, an estimated 28.3 million

surgical and nonsurgical procedures

were performed during 18.8 million

ambulatory surgery visits (table 1).

+ The 18.8 million ambulatory surgery

visits accounted for 49 percent of the

combined total of ambulatory surgery

visits and inpatient discharges with

surgical and nonsurgical procedures

(38.4 million) (figure 1).

+ An estimated 16.0 million

(85 percent) of the ambulatory

surgery visits occurred in hospitals

and 2.9 million (15 percent) occurred

in freestanding centers (table 2,

figure 2).

+ Females had significantly more

ambulatory surgery visits (10.7

million) than males (8.2 million) and

a significantly higher rate of visits

(80.2 per 1,000 population) compared

with males (65.0 per 1,000

population) (table 3).

+ The rate of ambulatory surgery visits

per 1,000 population was higher for

males (36.0) than for females (26.2)

under 15 years of age and higher for

females than for males for the age

groups 15–44 (63.4 versus 39.2) and

45–64 years (105.1 versus 88.4).

However, there was no significant

difference in the rates for males

(197.4) and females (173.9) 65 years

of age and over (figure 3).

+ Almost 90 percent of ambulatory

surgery visits were discharged to their

Abstract

Objectives—This report presents estimates of surgical and nonsurgical

procedures done on an ambulatory basis in hospitals and freestanding ambulatory

surgery centers in the United States during 1994. Data are presented by types of

facilities, age, sex, geographic region, and disposition for ambulatory surgery visits.

Major categories of procedures and diagnoses are shown by age, sex, and region.

Methods—The estimates are based on data collected from the National Survey

of Ambulatory Surgery, conducted for the first time in 1994 by the National Center

for Health Statistics. The 1994 data were abstracted from 118,000 medical records

in 494 hospitals and freestanding ambulatory surgery centers.

Keywords: National Survey of Ambulatory Surgery v procedures v diagnoses

v outpatients

Acknowledgments

This report was prepared in the Division of Health Care Statistics. The staff of the Hospital Care Statistics Branch processed the data and assisted

in developing the report. Edmund J. Graves helped prepare the tables, Maria Owings produced the standard errors, Elaine Wood verified the data,

and Brenda S. Gillum helped review the data. Eileen McCarthy, of the Technical Services Branch, assisted in creating the diagnostic and procedure

categories. Clara Holland, formerly in the Division of Data Processing, was responsible for data processing and medical coding. Iris Shimizu, Office

of Research and Methodology, developed the statistical design of the survey and assisted with estimation and variances. Robert Rose, under

contract with the Systems Integration Group of TRW, designed and ran the data editing programs. Other computer programming was done by

Rong Cai, Flora Lan, and Jerry Lin under contract with the OAO Corporation. Fieldwork and data collection activities were completed under a

contractual agreement with the U.S. Bureau of the Census. Stephanie Ventura of the Division of Vital Statistics was the peer reviewer. The report

was edited by Klaudia Cox and typeset by Annette F. Holman of the Publications Branch, Division of Data Services.

Number 283 + March 14, 1997

From Vital and Health Statistics of the CENTERS FOR DISEASE CONTROLAND PREVENTION/National Center for Health Statistics

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Disease Control and Prevention

National Center for Health Statistics

CENTERS FOR DISEASE CONTROL AND PREVENTION
customary residence, but 3.1 percent

went to observation status and

1.6 percent were admitted to hospitals

as inpatients (table 4).

Ambulatory procedures

+ Four procedures were performed

more than a million times on

ambulatory patients: extraction of

lens (1,989,000), endoscopy of large

intestine (1,836,000), insertion of

prosthetic lens (1,575,000), and

endoscopy of small intestine

(1,242,000) (figure 4, table 5 ).

+ Females had higher rates per 10,000

population than males for ambulatory

procedures such as release of carpal

tunnel (17.2 versus 9.4), operations

on eyelids (10.3 versus 7.1),

extraction (94.0 versus 58.7) and

insertion (74.1 versus 46.8) of lens,

laparoscopy (27.2 versus 2.4),

laparoscopic cholecystectomy (12.0

versus 2.9), and excision and repair

of bunion and other toe deformity

(16.0 versus 2.4) (tables 6 and 7).

+ Males had higher rates per 10,000

population than females for

ambulatory procedures such as

myringotomy with insertion of tube

(27.0 versus 17.9), adenoidectomy

without tonsillectomy (7.6 versus

4.2), bronchoscopy (7.4 versus 5.0),

cardiac catheterization (15.7 versus

9.4), repair of inguinal hernia (35.9

versus 3.7), cystoscopy (37.6 versus

23.4), reduction of fracture (9.3

versus 5.6), arthroscopy of knee (27.1

versus 17.1), excision of semilunar

cartilage of knee (19.4 versus 10.8),

and replacement or other repair of

knee (8.9 versus 5.9).

+ Ambulatory procedures performed

more than 100,000 times on children

under 15 years old included

myringotomy (556,000),

tonsillectomy (263,000),

adenoidectomy without tonsillectomy

(142,000), and operations on teeth,

gums, and alveoli (159,000).

+ A variety of ambulatory procedures

were performed more than 300,000

times on persons 15–44 years of age:

dilation and curettage of uterus

(386,000), endoscopy of large

intestine (349,000), excision or

destruction of lesion or tissue of skin

and subcutaneous tissue (342,000),

arthroscopy of knee (326,000),

laparoscopy (321,000), endoscopy of

small intestine (315,000), and

bilateral destruction or occlusion of

fallopian tubes (314,000).

Table 1. Number and rate of visits or discharges and procedures by type of patient: United States, 1994

Utilization measure

Total Ambulatory1 Inpatient2

Estimate

Standard

error Estimate

Standard

error Estimate

Standard

error

Number of visits or discharges in thousands3 ................. 38,436 1,051 18,850 806 19,587 674

Rate of visits or discharges per 1,000 population3 .............. 148.4 4.0 72.8 3.1 75.6 2.6

Number of procedures in thousands ....................... 68,989 2,043 28,278 1,210 40,710 1,646

Rate of procedures per 1,000 population .................... 266.4 7.9 109.2 4.7 157.2 6.4

1Data from the 1994 National Survey of Ambulatory Surgery.

2Data from the 1994 National Hospital Discharge Survey.

3Ambulatory surgery visits or discharges of hospital inpatients with procedures.

Visits/discharges Procedures

0

10

20

30

40

50

60

70

Number in millions

Inpatient Ambulatory

Figure 1. Utilization measures for ambulatory surgery visits and discharges of hospital

inpatients with procedures: United States, 1994

Table 2. Number and rate of ambulatory surgery visits and procedures, by type of facility: United States, 1994

Utilization measure

All facilities Hospitals Freestanding centers

Estimate

Standard

error Estimate

Standard

error Estimate

Standard

error

Number of visits in thousands ...................... 18,850 806 15,973 742 2,877 245

Rate of visits per 1,000 population ................... 72.8 3.1 61.7 2.9 11.1 0.9

Number of procedures in thousands .................. 28,278 1,210 23,969 1,116 4,309 380

Rate of procedures per 1,000 population ............... 109.2 4.7 92.6 4.3 16.6 1.5

2 Advance Data No. 283 + March 14, 1997
+ For persons 45–64 years of age,

endoscopy of large intestine

(661,000) and endoscopy of small

intestine (418,000) were frequent

ambulatory procedures.

+ Common ambulatory procedures for

persons 65 years of age and over

were extraction of lens (1,658,000),

insertion of prosthetic lens

(1,305,000), endoscopy of large

intestine (815,000), and endoscopy of

small intestine (488,000).

Diagnoses for ambulatory surgery

visits

+ Diagnoses for 500,000 or more

ambulatory surgery visits included

cataract (1,828,000); malignant

neoplasms (830,000); benign

neoplasms (1,009,000), especially

benign neoplasms of colon (518,000);

rheumatism (567,000); and otitis

media and Eustachian tube disorders

(526,000) (table 8).

+ Rates of ambulatory surgery visits per

10,000 population were higher for

females than for males for first-listed

diagnoses of carpal tunnel syndrome

(16.4 versus 9.2), glaucoma (6.6

versus 4.0), cataract (86.9 versus

53.4), gastritis and duodenitis (16.9

versus 11.3), cholelithiasis (10.6

versus 2.8), rheumatism (25.8 versus

17.7), acquired deformities of toe (8.7

versus 1.6), abdominal pain (6.7

versus 3.7), and visit for sterilization

(21.3 versus 3.8) (tables 9 and 10).

+ Rates of ambulatory surgery visits per

10,000 population were higher for

males than for females for first-listed

diagnoses of malignant neoplasm of

skin (8.2 versus 5.8), benign

neoplasm of colon (23.8 versus 16.3),

otitis media and Eustachian tube

disorders (24.4 versus 16.4), heart

disease (14.5 versus 9.0), inguinal

hernia (34.2 versus 3.5), calculus of

kidney and ureter (7.6 versus 5.1),

hematuria (5.7 versus 3.2), internal

derangement of knee (8.8 versus 5.6),

fractures (13.4 versus 8.2), and

current tear of medial cartilage or

meniscus of knee (11.9 versus 5.6).

Introduction

This is the first report to present

data from the National Survey of

Ambulatory Surgery (NSAS). The

NSAS was initiated by the National

Center for Health Statistics in 1994 to

gather and disseminate data about

ambulatory surgery. For the NSAS,

ambulatory surgery refers to surgical

and nonsurgical procedures performed

on an ambulatory (outpatient) basis in a

hospital or freestanding center’s general

operating rooms, dedicated ambulatory

surgery rooms, and other specialized

rooms, such as endoscopy units and

cardiac catheterization labs.

Ambulatory surgery has been

increasing in the United States since the

early 1980’s. Two major reasons for the

increase are advances in medical

technology and cost-containment

initiatives. The medical advances

include improvements in anesthesia,

which enable patients to regain

consciousness more quickly with fewer

aftereffects, and better analgesics for

relief of pain. In addition, minimally

invasive and noninvasive procedures are

being developed and performed with

increasing frequency. Examples include

laser surgery, laparoscopy, and

endoscopy. These medical advances

have made surgery less complex and

risky (1).

At the same time, concern about

rising health care costs led to changes in

the Medicare program that encouraged

the development of ambulatory surgery.

In the early 1980’s, the Medicare

program was expanded to cover care in

ambulatory surgery centers, and a

prospective payment system based on

diagnosis-related groups (DRG’s) was

adopted for hospital inpatient care that

created strong financial incentives for

hospitals to shift less complex surgery

to outpatient settings. Many State

Medicaid plans and private insurers

followed the lead of the Medicare

program and adopted similar policies

(2).

As these changes went into effect,

many types of surgeries formerly done

only on inpatients increasingly were

performed during ambulatory visits to

hospitals. In addition, the number of

freestanding ambulatory surgery centers

grew from 239 in 1983 (3) to more than

1,800 in 1993 (4).

The National Hospital Discharge

Survey (NHDS), which has been

conducted by the National Center for

Health Statistics every year since 1965,

includes information on surgical and

nonsurgical procedures performed in

inpatient settings (5). Although NHDS

remains a good source of data for

procedures that can only be done on an

inpatient basis, such as open-heart

surgery or cesarean section, NHDS

estimates have become incomplete for

procedures that can be performed on an

Ambulatory surgery visits

15%

Freestanding

centers

85%

Hospitals

Figure 2. Percent distribution of ambulatory surgery visits by type of facility:

United States, 1994

Advance Data No. 283 + March 14, 1997 3
ambulatory basis. The NSAS was

undertaken to obtain information about

ambulatory procedures. For many types

of procedures, data from both the NHDS

and the NSAS are now required to

obtain national estimates. A report that

combines the procedure data from the

two surveys is forthcoming.

Information on ambulatory

procedures is also collected in two other

NCHS surveys. The National

Ambulatory Medical Care Survey

obtains information on procedures

ordered or performed during visits to

physicians’ offices (6), and the National

Hospital Ambulatory Medical Care

Survey collects data on procedures

ordered or performed during visits to

hospital outpatient and emergency

departments (7–8).

This report provides the first

detailed data from the NSAS. For

perspective, the NSAS data on

ambulatory procedures in 1994 are

compared with estimates of inpatient

procedures from the 1994 NHDS (5) in

table 1. Estimates from the NSAS are

presented for hospitals and freestanding

facilities in table 2. Estimates by age,

sex, and geographic region are shown in

table 3 and by disposition of the

ambulatory surgery visit in table 4. The

types of procedures performed during

these visits (tables 5–7), and diagnoses

(tables 8–10) are also shown.

Methods

Source of data

Following a feasibility study in

1988–91 and a pretest in 1993, the

NSAS was conducted for the first time

in 1994. This survey covers surgical and

nonsurgical procedures performed on an

ambulatory basis in hospitals and

freestanding ambulatory surgery centers.

The hospital universe includes

noninstitutional hospitals exclusive of

Federal, military, and Department of

Veterans Affairs hospitals, located in the

50 States and the District of Columbia.

Only short-stay hospitals (hospitals with

an average length of stay for all patients

of fewer than 30 days) or those whose

specialty is general (medical or surgical)

or children’s general are included in the

survey. These hospitals must also have

six beds or more staffed for patient use.

The universe definition is the same as

that used for the National Hospital

Discharge Survey (5). The sampling

frame for the hospital universe consists

of eligible hospitals listed in the 1993

SMG Hospital Market Database (9).

The universe of freestanding

facilities includes the freestanding

ambulatory surgery centers listed in the

1993 SMG Freestanding Outpatient

Surgery Center Database (10) and/or

Medicare-certified facilities included in

the Health Care Financing

Administration Provider-of-Services file

(11). Facilities specializing in dentistry,

podiatry, pain block, abortion, family

planning, or birthing are excluded. A

detailed description of the development

and operation of the NSAS will be

provided in a forthcoming report.

Table 3. Number, percent distribution, and rate of ambulatory surgery visits by sex, age,

and region: United States, 1994

Age and region

Both sexes Male Female

Estimate

Standard

error Estimate

Standard

error Estimate

Standard

error

Number in thousands

Total.......................... 18,850 806 8,178 362 10,671 457

Age

Under 15 years ................... 1,790 93 1,056 57 734 41

15–44 years ..................... 6,040 271 2,292 113 3,748 171

45–64 years ..................... 4,936 231 2,170 105 2,766 132

65 years and over ................. 6,083 305 2,660 137 3,423 176

Region

Northeast ...................... 4,233 378 1,846 186 2,386 197

Midwest ....................... 4,896 472 2,131 213 2,765 265

South ......................... 6,251 449 2,654 182 3,597 274

West . . . . . . . . . . . . . . . . . . . . . . . . . 3,469 289 1,546 136 1,923 158

Percent distribution

Total.......................... 100.0 . . . 100.0 . . . 100.0 . . .

Age

Under 15 years . . . . . . . . . . . . . . . . . . . 9.5 0.3 12.9 0.4 6.9 0.2

15–44 years ..................... 32.0 0.4 28.0 0.6 35.1 0.6

45–64 years ..................... 26.2 0.5 26.5 0.5 25.9 0.5

65 years and over ................. 32.3 0.8 32.5 0.8 32.1 0.9

Region

Northeast ...................... 22.5 1.8 22.6 2.0 22.4 1.6

Midwest ....................... 26.0 2.2 26.1 2.3 25.9 2.2

South ......................... 33.2 1.9 32.5 1.7 33.7 2.1

West . . . . . . . . . . . . . . . . . . . . . . . . . 18.4 1.3 18.9 1.4 18.0 1.3

Rate per 1,000 population

Total.......................... 72.8 3.1 65.0 2.9 80.2 3.4

Age

Under 15 years ................... 31.2 1.6 36.0 1.9 26.2 1.5

15–44 years ..................... 51.4 2.3 39.2 1.9 63.4 2.9

45–64 years ..................... 97.1 4.5 88.4 4.3 105.1 5.0

65 years and over ................. 183.4 9.2 197.4 10.2 173.9 9.0

Region

Northeast ...................... 82.5 7.4 74.8 7.5 89.6 7.4

Midwest ....................... 79.9 7.7 71.6 7.1 87.8 8.4

South ......................... 69.5 5.0 61.2 4.2 77.3 5.9

West . . . . . . . . . . . . . . . . . . . . . . . . . 61.5 5.1 55.3 4.9 67.6 5.5

. . . Category not applicable.

4 Advance Data No. 283 + March 14, 1997
Sample design

The NSAS uses a multistage

probability design with independent

samples of hospitals and freestanding

ambulatory surgery centers selected at

the first or second stages and visits to

these facilities selected at the final stage.

The NSAS sample includes all facilities

with a high annual volume of

ambulatory procedures. The remaining

sample of facilities is selected using a

three-stage stratified cluster design.

The first stage consists of a

selection of a subsample of the primary

sampling units (PSU’s) used in the

1985–94 National Health Interview

Survey (12). PSU’s are counties, a

group of counties, county equivalents

(such as parishes or independent cities),

or towns and townships (for some

PSU’s in New England). The second

stage consists of a selection of facilities

from the sample PSU’s.

At the third stage, a systematic

random sample of ambulatory surgery

visits is selected. Sampled visits are

drawn from all locations within a

facility where ambulatory surgery is

performed, including main or general

operating rooms, all dedicated

ambulatory surgery rooms, cystoscopy

and endoscopy units, cardiac

catheterization labs, and laser procedure

rooms (in-scope locations). However,

locations within hospitals dedicated

exclusively to abortion, dentistry,

podiatry, pain block, or small procedures

(sometimes referred to as ‘‘lump and

bump’’ rooms) are not included. The

exclusion of these specialty locations, as

well as the exclusion of specialty

facilities, were recommended based on

the feasibility study for the NSAS.

There were 751 hospitals and

freestanding ambulatory surgery centers

in the 1994 NSAS sample. Of these,

134 were found to be out of scope

(ineligible) because they went out of

business, performed less than 50

ambulatory procedures in the previous

year, or otherwise failed to meet the

criteria for NSAS. Of the 617 in-scope

(eligible) facilities, 494 responded to the

survey, for an overall response rate of

80 percent. The response rate was

88 percent for hospitals and 70 percent

for freestanding facilities.

Data collection

Sample selection and abstraction of

information from medical records were

performed at the facilities. Facility staff

did the sampling in about 45 percent of

facilities that participated in the 1994

survey, and facility staff abstracted the

data in approximately two-thirds of the

participating facilities. In the remaining

facilities, the work was performed by

personnel of the U.S. Bureau of the

Census acting on behalf of NCHS.

Completed abstract forms were sent to

NCHS for coding, editing, and

weighting.

The abstract form (figure 5)

contains items relating to the personal

characteristics of the patients such as

age, sex, race, and ethnicity. There are

administrative items such as date of

procedure, disposition, and expected

sources of payment. The medical

information includes up to seven

diagnoses and six procedures, which are

coded according to the International

Classification of Diseases, 9th Revision,

Clinical Modification (ICD–9–CM) (13).

Estimation and reliability of

estimates

Statistics from the NSAS are

derived by a multistage estimation

procedure that produces essentially

unbiased estimates. The estimation

procedure has three basic components:

(a) inflation by reciprocals of the

Under 15 years 15 44 years 45 64 years 65 years and over 0

50

100

150

200

Rate per 1,000 population

Males Females

Figure 3. Rate of ambulatory surgery visits by age and sex: United States, 1994

Table 4. Number and percent distribution of ambulatory surgery visits by disposition of

visit: United States, 1994

Disposition

Number in thousands Percent distribution

Estimate

Standard

error Estimate

Standard

error

All dispositions ..................... 18,850 806 100.0 . . .

Routine discharge to customary residence .... 16,887 782 89.6 1.6

Discharge to observation status. . . . . . . . . . . 581 78 3.1 0.4

Discharge to recovery care center . . . . . . . . . * ... * ...

Admitted to hospital as inpatient . . . . . . . . . . 311 42 1.6 0.2

Surgery canceled or terminated . . . . . . . . . . . 17 2 0.1 1

Other dispositions . . . . . . . . . . . . . . . . . . . 141 37 0.7 0.2

Disposition not stated . . . . . . . . . . . . . . . . . 678 145 3.6 0.8

. . . Category not applicable.

* Figure does not meet standard of reliability or precision.

1

Standard error is 0.01.

Advance Data No. 283 + March 14, 1997 5
probabilities of sample selection, (b)

adjustment for nonresponse, and (c)

population weighting ratio adjustments.

The statistics presented in this

report are based on a sample, and

therefore may differ from the figures

that would be obtained if a complete

census had been taken. The standard

error is primarily a measure of sampling

variability that occurs by chance

because only a sample rather than the

entire universe is surveyed. Standard

errors for the estimates in this report

were calculated with SUDAAN

software, which takes into account the

complex sample design. A description of

the software and approach it uses has

been published (14).

The chances are about 32 in 100

that an estimate from the sample would

differ from a complete census by more

than the standard error. The chances are

5 in 100 that the difference would be

more than twice the standard error, and

about 1 in 100 that the difference would

be more than 2.5 times as large as the

standard error. The relative standard

error is expressed as a percent of an

estimate and can be multiplied by the

estimate to obtain the standard error.

Because of low reliability, estimates

that have a relative standard error of

more than 30 percent or are based on a

sample of fewer than 30 records are not

presented. For these estimates, only an

asterisk (*) appears in the tables.

Estimates preceded by an asterisk (*)

are based on fewer than 60 records and

are also considered to have low

reliability.

Definitions and limitations

The estimates of procedures shown

in this report include surgical procedures

(such as tonsillectomy), diagnostic

procedures (such as cystoscopy), and

other therapeutic procedures (such as

injection or infusion of cancer

chemotherapeutic substance) reported on

the medical record. Data are shown for

all-listed procedures, which are all

occurrences of the procedures coded

regardless of their order on the medical

record. In contrast, diagnostic data for

ambulatory surgery visits are for the

diagnosis listed first on the medical

record.

Because certain freestanding

facilities and certain specialized

locations within hospitals and

freestanding facilities are excluded from

the NSAS design, ambulatory

procedures done in some specialties are

not completely measured by the survey.

Excluded specialties include dentistry,

podiatry, abortion, family planning,

birthing, pain block, and small

procedures (such as removal of skin

lesion). However, procedures in these

specialties performed in general

operating rooms or other in-scope

locations are included in the survey.

In addition, the NSAS does not

completely measure ambulatory

procedures that are performed in

locations such as physicians’ offices, for

example, endoscopies of large and small

intestine, injections of therapeutic

substances, skin biopsies, and plastic

surgery. The National Ambulatory

Medical Care Survey has data about

procedures ordered or performed in

physicians’ offices (6) and the National

Hospital Ambulatory Medical Care

Survey provides information about

procedures ordered or performed in

hospital outpatient and emergency

departments (7, 8).

The determination of whether an

ambulatory surgery facility is a hospital

or a freestanding center is based on the

SMG universe from which the facility is

selected. In most cases, it is apparent

whether a facility is a hospital or a

freestanding ambulatory surgery center.

However, some facilities are not easily

classified. For example, a

‘‘freestanding’’ facility may be owned

by a hospital but located some distance

away. If such a facility is listed

separately in the 1993 SMG

Freestanding Outpatient Surgery Center

Database (10) and is selected into the

NSAS sample from this universe, it is

considered a freestanding facility.

The distinction between ambulatory

and inpatient procedures is not always

clear. According to the 1994 NSAS, an

estimated 1.6 percent of ambulatory

surgery visits were for patients

subsequently admitted to the hospital as

inpatients. Some of these patients had

procedures that are currently performed

exclusively on inpatients, such as

coronary artery bypass graft, in addition

to diagnostic procedures such as cardiac

catheterization. These visits and their

suspected ‘‘inpatient’’ procedures have

not been eliminated because they are

operationally part of the survey design,

i.e., the procedure is listed in the

medical record associated with the

sampled visit. However, researchers who

use the NSAS public use files may

delete them, depending on their analytic

objectives.

Estimates in the tables have been

rounded to the nearest thousand.

Therefore, figures within tables do not

always add to the totals. Rates and

percents were calculated from

unrounded figures and may not agree

Extraction

of lens

Endoscopy Insertion of Endoscopy

of small

0

0.5

1.0

1.5

2.0

Number in millions

lens intestine

of large

intestine

prosthetic

Figure 4. Number of selected procedures performed on ambulatory patients:

United States, 1994

6 Advance Data No. 283 + March 14, 1997
Table 5. Number of ambulatory surgery procedures, by procedure category, sex, and age: United States, 1994

[Procedure categories and code numbers are based on the International Classification of Diseases, 9th Revision, Clinical Modification (ICD–9–CM)]

Procedure category and ICD–9–CM code Total

Sex Age

Male Female

Under

15 years

15–44

years

45–64

years

65 years

and over

Number in thousands

All procedures ......................................... 28,278 12,331 15,947 2,446 9,006 7,497 9,330

Operations on the nervous system .........................01–05 979 378 601 8 415 336 220

Injection of agent into spinal canal ................... 03.91–03.92 339 145 194 * 113 114 110

Release of carpal tunnel ............................. 04.43 348 118 230 * 159 123 66

Operations on the eye................................ 08–16 4,551 1,771 2,781 147 222 729 3,453

Operations on eyelids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 08 226 90 137 22 27 62 116

Extraction of lens ............................... 13.1–13.6 1,989 738 1,251 * 45 271 1,658

Insertion of prosthetic lens (pseudophakos) ................... 13.7 1,575 588 986 * 32 229 1,305

Operations on the ear .................................18–20 870 503 367 680 92 39 59

Myringotomy with insertion of tube........................ 20.01 579 340 239 556 14 *5 *

Operations on the nose, mouth, and pharynx ................. 21–29 2,007 1,041 966 705 785 344 172

Turbinectomy ..................................... 21.6 160 83 77 14 101 37 *9

Repair and plastic operations on the nose .................... 21.8 256 136 120 10 167 49 29

Operations on nasal sinuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 409 208 201 48 181 142 39

Operations on teeth, gums, and alveoli .....................23–24 222 124 98 159 44 11 *9

Tonsillectomy with or without adenoidectomy .............. 28.2–28.3 378 163 215 263 106 * *

Adenoidectomy without tonsillectomy ...................... 28.6 152 96 56 142 *8 * *

Operations on the respiratory system ...................... 30–34 341 191 150 27 58 125 132

Bronchoscopy with or without biopsy .............. 33.21–33.24,33.27 160 93 66 * 15 57 79

Operations on the cardiovascular system .....................35–39 688 378 309 * 125 271 276

Cardiac catheterization ........................... 37.21–37.23 323 198 125 * 37 150 131

Operations on the digestive system ........................42–54 6,174 2,838 3,336 181 1,812 1,963 2,217

Esophagoscopy and gastroscopy ............42.21–42.24,44.11–44.14 223 101 122 4 48 70 101

Dilation of esophagus ............................... 42.92 241 124 117 *3 37 83 118

Endoscopy of small intestine with or without biopsy .... 45.11–45.14,45.16 1,242 543 699 20 315 418 488

Endoscopy of large intestine with or without biopsy ........ 45.21–45.25 1,836 837 1,000 12 349 661 815

Endoscopic polypectomy of large intestine................... 45.42 462 257 206 * 36 175 250

Laparoscopic cholecystectomy .......................... 51.23 195 36 159 * 100 64 30

Repair of inguinal hernia ........................... 53.0–53.1 501 452 49 87 158 118 138

Laparoscopy ..................................... 54.21 392 31 361 *5 321 55 11

Operations on the urinary system..........................55–59 1,415 852 563 78 312 419 606

Cystoscopy with or without biopsy .................... 57.31–57.33 784 473 311 31 160 232 361

Operations on the male genital organs ......................60–64 549 549 . . . 159 147 97 146

Operations on the female genital organs .....................65–71 2,060 . . . 2,060 10 1,554 402 94

Bilateral destruction or occlusion of fallopian tubes........... 66.2–66.3 319 . . . 319 – 314 * –

Hysteroscopy..................................... 68.12 198 . . . 198 – 116 71 10

Dilation and curettage of uterus .......................... 69.0 597 . . . 597 * 386 167 43

Operations on the musculoskeletal system ....................76–84 3,727 1,954 1,772 158 1,884 1,168 517

Partial excision of bone .....................76.2–76.3,77.6–77.8 227 112 115 10 110 79 28

Reduction of fracture .......................... 76.7,79.0–79.3 192 117 75 44 94 33 21

Removal of implanted devices from bone ............... 76.97,78.6 170 93 77 16 88 45 21

Excision and repair of bunion and other toe deformities............ 77.5 243 30 213 *5 82 101 55

Arthroscopy of knee................................. 80.26 569 340 228 10 326 163 70

Excision of semilunar cartilage of knee ...................... 80.6 387 244 143 *5 193 127 62

Replacement or other repair of knee ..........81.42–81.47,81.54–81.55 191 112 79 * 117 53 18

Operations on muscle, tendon, fascia and bursa ...............82–83 580 280 299 28 269 194 90

Operations on the integumentary system .....................85–86 2,271 668 1,603 108 877 741 546

Biopsy of breast ............................... 85.11–85.12 369 *5 364 * 131 148 87

Local excision of lesion of breast (lumpectomy)................ 85.21 355 *12 343 * 146 131 76

Excision or destruction of lesion or tissue of skin and subcutaneous

tissue...................................... 86.2–86.4 900 440 460 69 342 249 240

Miscellaneous diagnostic and therapeutic procedures .............87–99 2,479 1,158 1,322 157 661 815 847

Arteriography and angiocardiography using contrast material .... 88.4–88.5 553 322 230 * 58 249 243

Injection or infusion of therapeutic or prophylactic substance .... 99.1–99.2 209 93 116 * 65 60 72

Operations on the endocrine system, operations on the hemic and lymphatic

system, and obstetrical procedures .............. 06–07,40–41,72–75 168 50 118 12 62 49 44

* Figure does not meet standard of reliability or precision.

. . . Category not applicable.

– Quantity zero.

Advance Data No. 283 + March 14, 1997 7
Table 6. Rate of ambulatory surgery procedures, by procedure category, sex, and age: United States, 1994

[Procedure categories and code numbers are based on the International Classification of Diseases, 9th Revision, Clinical Modification (ICD–9–CM)]

Procedure category and ICD–9–CM code Total

Sex Age

Male Female

Under

15 years

15–44

years

45–64

years

65 years

and over

Rate per 10,000 population

All procedures ......................................... 1,092.1 979.9 1,198.2 426.5 765.9 1,474.4 2,813.7

Operations on the nervous system .........................01–05 37.8 30.0 45.2 1.4 35.3 66.1 66.3

Injection of agent into spinal canal.................... 03.91–03.92 13.1 11.5 14.6 * 9.6 22.5 33.3

Release of carpal tunnel .............................. 04.43 13.4 9.4 17.2 * 13.5 24.1 20.0

Operations on the eye.................................08–16 175.8 140.7 208.9 25.6 18.9 143.4 1,041.4

Operations on eyelids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 08 8.7 7.1 10.3 3.9 2.3 12.2 34.9

Extraction of lens ............................... 13.1–13.6 76.8 58.7 94.0 * 3.8 53.3 500.1

Insertion of prosthetic lens (pseudophakos) ................... 13.7 60.8 46.8 74.1 * 2.8 45.0 393.6

Operations on the ear .................................18–20 33.6 40.0 27.6 118.7 7.8 7.7 17.7

Myringotomy with insertion of tube........................ 20.01 22.4 27.0 17.9 96.9 1.2 *1.0 *

Operations on the nose, mouth, and pharynx ..................21–29 77.5 82.8 72.6 123.0 66.8 67.7 52.0

Turbinectomy ...................................... 21.6 6.2 6.6 5.8 2.4 8.6 7.2 *2.7

Repair and plastic operations on the nose .................... 21.8 9.9 10.8 9.0 1.8 14.2 9.7 8.8

Operations on nasal sinuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 15.8 16.5 15.1 8.3 15.4 27.9 11.7

Operations on teeth, gums, and alveoli .....................23–24 8.6 9.9 7.4 27.8 3.7 2.1 *2.6

Tonsillectomy with or without adenoidectomy .............. 28.2–28.3 14.6 13.0 16.2 45.9 9.0 * *

Adenoidectomy without tonsillectomy ....................... 28.6 5.9 7.6 4.2 24.8 *0.6 * *

Operations on the respiratory system .......................30–34 13.2 15.2 11.3 4.6 4.9 24.5 39.7

Bronchoscopy with or without biopsy .............. 33.21–33.24,33.27 6.2 7.4 5.0 * 1.3 11.3 23.7

Operations on the cardiovascular system .....................35–39 26.6 30.1 23.2 * 10.6 53.2 83.3

Cardiac catheterization ........................... 37.21–37.23 12.5 15.7 9.4 * 3.2 29.6 39.4

Operations on the digestive system ........................42–54 238.4 225.6 250.6 31.6 154.1 386.1 668.7

Esophagoscopy and gastroscopy ............42.21–42.24,44.11–44.14 8.6 8.0 9.2 0.7 4.1 13.9 30.4

Dilation of esophagus ............................... 42.92 9.3 9.9 8.8 *0.5 3.1 16.3 35.7

Endoscopy of small intestine with or without biopsy ..... 45.11–45.14,45.16 48.0 43.1 52.5 3.5 26.8 82.3 147.2

Endoscopy of large intestine with or without biopsy ......... 45.21–45.25 70.9 66.5 75.1 2.0 29.7 129.9 245.6

Endoscopic polypectomy of large intestine................... 45.42 17.9 20.4 15.4 * 3.1 34.5 75.3

Laparoscopic cholecystectomy .......................... 51.23 7.5 2.9 12.0 * 8.5 12.6 9.0

Repair of inguinal hernia ........................... 53.0–53.1 19.3 35.9 3.7 15.2 13.4 23.2 41.5

Laparoscopy ..................................... 54.21 15.1 2.4 27.2 *0.9 27.3 10.8 3.2

Operations on the urinary system..........................55–59 54.6 67.7 42.3 13.6 26.5 82.4 182.9

Cystoscopy with or without biopsy .................... 57.31–57.33 30.3 37.6 23.4 5.4 13.6 45.6 108.8

Operations on the male genital organs ......................60–64 21.2 43.6 . . . 27.7 12.5 19.0 43.9

Operations on the female genital organs .....................65–71 79.6 . . . 154.8 1.8 132.1 79.0 28.4

Bilateral destruction or occlusion of fallopian tubes........... 66.2–66.3 12.3 . . . 24.0 – 26.7 * –

Hysteroscopy..................................... 68.12 7.6 . . . 14.9 – 9.9 14.1 3.1

Dilation and curettage of uterus .......................... 69.0 23.0 . . . 44.8 * 32.8 32.8 13.1

Operations on the musculoskeletal system ....................76–84 143.9 155.3 133.2 27.5 160.2 229.6 156.1

Partial excision of bone .....................76.2–76.3,77.6–77.8 8.8 8.9 8.6 1.7 9.4 15.5 8.4

Reduction of fracture .......................... 76.7,79.0–79.3 7.4 9.3 5.6 7.7 8.0 6.5 6.2

Removal of implanted devices from bone ................ 76.97,78.6 6.6 7.4 5.8 2.8 7.5 8.8 6.3

Excision and repair of bunion and other toe deformities............ 77.5 9.4 2.4 16.0 *0.9 7.0 19.8 16.7

Arthroscopy of knee................................. 80.26 22.0 27.1 17.1 1.8 27.7 32.1 21.0

Excision of semilunar cartilage of knee ...................... 80.6 14.9 19.4 10.8 *0.8 16.4 25.0 18.8

Replacement or other repair of knee ..........81.42–81.47,81.54–81.55 7.4 8.9 5.9 * 9.9 10.4 5.6

Operations on muscle, tendon, fascia and bursa ...............82–83 22.4 22.3 22.5 4.8 22.8 38.1 27.2

Operations on the integumentary system .....................85–86 87.7 53.1 120.4 18.8 74.6 145.7 164.6

Biopsy of breast ............................... 85.11–85.12 14.2 *0.4 27.4 * 11.2 29.1 26.3

Local excision of lesion of breast (lumpectomy)................ 85.21 13.7 *1.0 25.8 * 12.5 25.7 23.0

Excision or destruction of lesion or tissue of skin and subcutaneous

tissue ..................................... 86.2–86.4 34.8 35.0 34.6 12.0 29.1 49.0 72.4

Miscellaneous diagnostic and therapeutic procedures .............87–99 95.8 92.0 99.3 27.4 56.2 160.3 255.3

Arteriography and angiocardiography using contrast material .... 88.4–88.5 21.3 25.6 17.3 * 5.0 49.1 73.2

Injection or infusion of therapeutic or prophylactic substance .... 99.1–99.2 8.1 7.4 8.7 * 5.6 11.7 21.6

Operations on the endocrine system, operations on the hemic and lymphatic

system, and obstetrical procedures ............... 06–07,40–41,72–75 6.5 3.9 8.9 2.2 5.3 9.6 13.3

* Figure does not meet standard of reliability or precision.

. . . Category not applicable.

– Quantity zero.

8 Advance Data No. 283 + March 14, 1997
Table 7. Relative standard errors for number and rate of ambulatory surgery procedures by procedure category, sex, and age:

United States, 1994

[Procedure categories and code numbers are based on the International Classification of Diseases, 9th Revision, Clinical Modification (ICD–9–CM)]

Procedure category and ICD–9–CM code Total

Sex Age

Male Female

Under

15 years

15–44

years

45–64

years

65 years

and over

Standard error as a percent of the number or rate of procedures

All procedures ......................................... 4.28 4.48 4.26 5.29 4.49 4.91 4.90

Operations on the nervous system .........................01–05 7.11 8.30 6.99 23.60 8.07 8.21 7.85

Injection of agent into spinal canal.................... 03.91–03.92 11.88 12.88 11.89 . . . 15.84 12.49 12.97

Release of carpal tunnel .............................. 04.43 5.98 7.61 6.43 . . . 8.09 7.23 9.18

Operations on the eye.................................08–16 5.78 6.21 5.88 12.58 11.05 6.87 6.06

Operations on eyelids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 08 8.32 10.26 9.68 20.93 16.65 13.19 8.90

Extraction of lens ............................... 13.1–13.6 6.56 6.86 6.70 . . . 21.68 7.96 6.62

Insertion of prosthetic lens (pseudophakos) ................... 13.7 5.88 6.12 6.13 . . . 17.47 7.20 5.98

Operations on the ear .................................18–20 5.93 6.18 6.46 6.19 10.27 15.64 12.58

Myringotomy with insertion of tube........................ 20.01 6.47 6.92 6.87 6.51 19.13 25.75 . . .

Operations on the nose, mouth, and pharynx ..................21–29 5.33 5.35 5.90 6.27 6.27 9.23 11.08

Turbinectomy ...................................... 21.6 10.59 10.80 12.57 18.35 11.44 15.80 22.91

Repair and plastic operations on the nose .................... 21.8 8.09 9.31 8.75 20.63 8.39 12.68 16.06

Operations on nasal sinuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 8.54 9.83 9.92 19.09 9.04 12.02 18.25

Operations on teeth, gums, and alveoli .....................23–24 15.55 16.49 16.37 19.94 19.43 23.37 23.61

Tonsillectomy with or without adenoidectomy .............. 28.2–28.3 7.15 7.68 8.08 7.17 8.63 . . . . . .

Adenoidectomy without tonsillectomy ....................... 28.6 9.34 10.37 11.59 9.42 29.40 . . . . . .

Operations on the respiratory system .......................30–34 7.86 9.72 8.73 20.22 12.81 9.74 10.68

Bronchoscopy with or without biopsy .............. 33.21–33.24,33.27 10.16 12.40 11.47 . . . 16.68 11.82 12.67

Operations on the cardiovascular system .....................35–39 9.57 10.95 9.72 . . . 9.65 12.80 10.09

Cardiac catheterization ........................... 37.21–37.23 14.17 13.90 16.63 . . . 18.88 16.71 13.84

Operations on the digestive system ........................42–54 6.27 6.37 6.36 7.93 5.41 7.04 7.68

Esophagoscopy and gastroscopy ............42.21–42.24,44.11–44.14 14.82 16.09 15.48 25.03 17.42 15.29 18.12

Dilation of esophagus ............................... 42.92 21.88 20.17 24.69 28.02 28.48 24.11 20.47

Endoscopy of small intestine with or without biopsy ..... 45.11–45.14,45.16 9.49 9.57 9.86 16.77 9.06 9.45 11.56

Endoscopy of large intestine with or without biopsy ......... 45.21–45.25 7.76 8.24 7.63 21.68 8.85 8.09 8.25

Endoscopic polypectomy of large intestine................... 45.42 10.45 11.50 10.33 . . . 12.05 12.12 11.23

Laparoscopic cholecystectomy .......................... 51.23 8.87 16.15 8.54 . . . 9.99 11.27 15.06

Repair of inguinal hernia ........................... 53.0–53.1 4.43 4.60 9.33 9.03 6.43 7.29 7.23

Laparoscopy ..................................... 54.21 6.25 14.47 6.36 28.38 6.29 14.99 18.68

Operations on the urinary system..........................55–59 8.33 8.89 9.45 17.70 10.09 9.34 9.10

Cystoscopy with or without biopsy .................... 57.31–57.33 10.28 10.40 11.86 23.66 11.77 10.26 11.55

Operations on the male genital organs ......................60–64 6.19 6.19 . . . 9.63 7.65 11.23 9.46

Operations on the female genital organs .....................65–71 5.12 . . . 5.12 21.56 5.50 7.99 10.55

Bilateral destruction or occlusion of fallopian tubes........... 66.2–66.3 7.47 . . . 7.47 . . . 7.57 . . . . . .

Hysteroscopy..................................... 68.12 8.15 . . . 8.15 . . . 8.67 12.72 18.23

Dilation and curettage of uterus .......................... 69.0 5.35 . . . 5.35 . . . 6.13 6.66 11.15

Operations on the musculoskeletal system ....................76–84 5.98 6.79 5.65 8.44 6.94 6.36 6.61

Partial excision of bone .....................76.2–76.3,77.6–77.8 6.94 8.88 7.71 26.37 9.36 8.90 12.95

Reduction of fracture .......................... 76.7,79.0–79.3 8.27 9.32 9.33 13.36 9.67 11.97 15.44

Removal of implanted devices from bone ................ 76.97,78.6 7.79 9.91 9.59 17.20 9.90 10.56 14.52

Excision and repair of bunion and other toe deformities............ 77.5 8.19 11.04 8.77 28.43 10.23 10.82 12.04

Arthroscopy of knee................................. 80.26 7.57 7.98 7.90 18.35 8.52 8.32 11.42

Excision of semilunar cartilage of knee ...................... 80.6 7.34 7.45 8.55 26.26 8.42 8.56 10.76

Replacement or other repair of knee ..........81.42–81.47,81.54–81.55 9.84 12.83 9.20 . . . 12.69 10.28 15.80

Operations on muscle, tendon, fascia and bursa ...............82–83 5.68 6.56 6.24 12.67 6.89 7.52 8.46

Operations on the integumentary system .....................85–86 5.02 7.57 4.87 8.49 5.72 5.53 5.94

Biopsy of breast ............................... 85.11–85.12 7.71 25.81 7.63 . . . 9.87 8.58 9.10

Local excision of lesion of breast (lumpectomy)................ 85.21 7.69 20.14 7.64 . . . 9.84 7.64 11.46

Excision or destruction of lesion or tissue of skin and subcutaneous

tissue...................................... 86.2–86.4 6.85 8.26 6.43 10.25 7.53 7.40 8.97

Miscellaneous diagnostic and therapeutic procedures .............87–99 10.60 9.27 12.43 10.07 14.05 10.78 10.65

Arteriography and angiocardiography using contrast material .... 88.4–88.5 14.00 12.80 17.08 . . . 19.74 17.21 13.77

Injection or infusion of therapeutic or prophylactic substance .... 99.1–99.2 14.60 13.94 17.07 . . . 19.70 14.03 16.69

Operations on the endocrine system, operations on the hemic and lymphatic

system, and obstetrical procedures ............... 06–07,40–41,72–75 8.73 10.83 10.15 15.55 15.47 11.27 12.81

. . . Category not applicable.

NOTE: The standard error of a number or rate in tables 5 or 6 can be obtained by multiplying the estimate by the corresponding relative standard error, shown as a percent, in this table.

Advance Data No. 283 + March 14, 1997 9
Table 8. Number of ambulatory surgery visits by first-listed diagnosis, sex, and age: United States, 1994

[Diagnostic categories and code numbers are based on the International Classification of Diseases, 9th Revision, Clinical Modification (ICD–9–CM)]

Category of first-listed diagnosis and ICD–9–CM code Total

Sex Age

Male Female

Under

15 years

15–44

years

45–64

years

65 years

and over

Number in thousands

All conditions .............................................. 18,850 8,178 10,671 1,790 6,040 4,936 6,083

Infectious and parasitic diseases ............................. 001–139 101 51 50 10 63 19 *9

Neoplasms........................................... 140–239 1,968 906 1,061 49 397 641 880

Malignant neoplasms ............................. 140–208,230–234 830 390 440 10 124 261 436

Malignant neoplasm of skin...................... 172–173,176.0,198.2 180 103 77 * 18 47 114

Malignant neoplasm of breast ....................... 174–175,198.81 127 * 125 * 25 57 45

Benign neoplasms..................................... 210–229 1,009 453 556 36 249 346 379

Benign neoplasm of colon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211.3 518 300 218 * 41 194 280

Lipoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 111 49 62 * 47 44 19

Endocrine, nutritional and metabolic diseases, and immunity disorders..... 240–279 123 42 81 * 42 42 37

Diseases of the nervous system and sense organs.................. 320–389 3,575 1,472 2,103 626 400 582 1,966

Carpal tunnel syndrome .................................. 354.0 334 116 218 * 151 118 64

Glaucoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365 137 50 88 * *5 26 104

Cataract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 366 1,828 672 1,156 6 30 256 1,536

Otitis media and Eustachian tube disorders .................... 381–382 526 308 218 498 16 *6 *

Diseases of the circulatory system ............................ 390–459 736 387 350 * 148 310 267

Heart disease ............... 391–392.0,393–398,402,404,410–416,420–429 302 183 119 * 26 128 142

Hemorrhoids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455 233 105 128 * 71 109 51

Diseases of the respiratory system ............................ 460–519 878 421 457 321 328 146 83

Deviated nasal septum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 470 149 81 68 *4 105 29 *

Chronic sinusitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 473 122 56 66 15 50 42 14

Chronic disease of tonsils and adenoids . . . . . . . . . . . . . . . . . . . . . . . . . . 474 370 165 204 268 95 * *

Diseases of the digestive system ............................ 520–579 3,116 1,573 1,543 223 888 928 1,078

Diseases of teeth and supporting structures .................... 520–525 135 71 64 88 37 *6 *

Diseases of esophagus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 530 424 209 215 8 107 144 167

Ulcer of stomach and small intestine ........................ 531–534 125 52 74 * 27 41 56

Gastritis and duodenitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 535 368 143 225 *4 100 115 148

Inguinal hernia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 550 476 430 46 79 151 114 131

Noninfectious enteritis and colitis ........................... 555–558 197 85 112 * 83 62 49

Diverticula of intestine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 562 320 135 184 * 14 91 214

Cholelithiasis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 574 176 35 141 * 84 57 35

Diseases of the genitourinary system .......................... 580–629 2,335 690 1,644 128 1,043 683 481

Calculus of kidney and ureter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 592 164 96 68 * 71 60 33

Hematuria............................................ 599.7 114 71 43 * 24 38 47

Benign mammary dysplasias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 610 176 * 174 * 72 73 29

Lump or mass in breast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 611.72 233 *5 228 * 95 87 50

Disorders of menstruation and other abnormal vaginal bleeding.... 626,627.0–627.1 269 . . . 269 * 141 104 23

Complications of pregnancy, childbirth, and the puerperium............. 630–676 234 . . . 234 * 231 * . . .

Abortion and ectopic and molar pregnancy ..................... 630–639 203 . . . 203 * 200 * . . .

Diseases of the skin and subcutaneous tissue..................... 680–709 476 224 252 34 207 127 108

Sebaceous cyst ........................................ 706.2 130 67 63 * 56 40 25

Diseases of the musculoskeletal system and connective tissue .......... 710–739 1,693 738 955 43 773 560 317

Arthropathies and related disorders .......................... 710–719 475 255 220 9 240 148 77

Internal derangement of knee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 717 186 111 75 * 114 48 20

Intervertebral disc disorders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 722 114 59 55 – 58 * 19

Lumbago ............................................ 724.2 111 47 64 * 38 37 35

Rheumatism, excluding back ............................. 725–729 567 223 344 15 264 200 87

Acquired deformities of toe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 735 136 21 116 * 44 56 33

Congenital anomalies .................................... 740–759 227 115 112 96 64 24 43

Symptoms, signs, and ill-defined conditions ...................... 780–799 1,011 414 597 56 324 316 314

Abdominal pain ........................................ 789.0 137 47 90 * 57 37 36

Injury and poisoning ..................................... 800–999 1,187 694 493 125 577 301 184

Fractures ......................................... 800–829 278 169 109 64 149 41 24

Current tear of medial cartilage or meniscus of knee ................. 836.0 224 149 75 * 114 78 29

Supplementary classification ................................V01–V82 1,068 402 666 52 532 221 263

Visit for sterilization ......................................V25.2 331 48 283 * 320 * –

Diseases of the blood and blood-forming organs, mental disorders, and certain

conditions originating in the perinatal period ......... 280–289,290–319,760–779 122 49 73 * 24 33 54

* Figure does not meet standard of reliability or precision.

. . . Category not applicable.

– Quantity zero.

10 Advance Data No. 283 + March 14, 1997
Table 9. Rate of ambulatory surgery visits by first-listed diagnosis, sex, and age: United States, 1994

[Diagnostic categories and code numbers are based on the International Classification of Diseases, 9th Revision, Clinical Modification (ICD–9–CM)]

Category of first-listed diagnosis

and ICD–9–CM code Total

Sex Age

Male Female

Under

15 years

15–44

years

45–64

years

65 years

and over

Rate per 10,000 population

All conditions .............................................. 728.0 649.9 801.8 312.2 513.7 970.7 1,834.5

Infectious and parasitic diseases ............................ 001–139 3.9 4.1 3.7 1.7 5.3 3.8 *2.6

Neoplasms........................................... 140–239 76.0 72.0 79.8 8.6 33.8 126.1 265.3

Malignant neoplasms ............................. 140–208,230–234 32.1 31.0 33.0 1.7 10.5 51.3 131.4

Malignant neoplasm of skin...................... 172–173,176.0,198.2 6.9 8.2 5.8 * 1.5 9.3 34.3

Malignant neoplasm of breast ....................... 174–175,198.81 4.9 * 9.4 * 2.1 11.2 13.5

Benign neoplasms..................................... 210–229 39.0 36.0 41.8 6.2 21.2 68.0 114.3

Benign neoplasm of colon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211.3 20.0 23.8 16.3 * 3.5 38.1 84.6

Lipoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 4.3 3.9 4.7 * 4.0 8.7 5.7

Endocrine, nutritional and metabolic diseases, and immunity disorders..... 240–279 4.8 3.3 6.1 * 3.6 8.3 11.1

Diseases of the nervous system and sense organs.................. 320–389 138.1 117.0 158.0 109.3 34.1 114.4 593.0

Carpal tunnel syndrome .................................. 354.0 12.9 9.2 16.4 * 12.9 23.2 19.4

Glaucoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365 5.3 4.0 6.6 * *0.4 5.2 31.5

Cataract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 366 70.6 53.4 86.9 1.1 2.5 50.4 463.1

Otitis media and Eustachian tube disorders ..................... 381–382 20.3 24.4 16.4 86.9 1.3 *1.3 *

Diseases of the circulatory system ............................ 390–459 28.4 30.7 26.3 * 12.6 61.1 80.5

Heart disease ............... 391–392.0,393–398,402,404,410–416,420–429 11.7 14.5 9.0 * 2.2 25.3 42.9

Hemorrhoids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455 9.0 8.4 9.6 * 6.0 21.5 15.3

Diseases of the respiratory system ........................... 460–519 33.9 33.5 34.3 56.1 27.9 28.6 25.2

Deviated nasal septum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 470 5.8 6.5 5.1 *0.7 8.9 5.8 *

Chronic sinusitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 473 4.7 4.5 4.9 2.6 4.3 8.3 4.2

Chronic disease of tonsils and adenoids . . . . . . . . . . . . . . . . . . . . . . . . . . 474 14.3 13.1 15.4 46.7 8.1 * *

Diseases of the digestive system ............................. 520–579 120.3 125.0 115.9 38.8 75.5 182.4 325.0

Diseases of teeth and supporting structures .................... 520–525 5.2 5.6 4.8 15.4 3.1 *1.2 *

Diseases of esophagus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 530 16.4 16.6 16.2 1.3 9.1 28.2 50.3

Ulcer of stomach and small intestine ......................... 531–534 4.8 4.1 5.5 * 2.3 8.1 17.0

Gastritis and duodenitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 535 14.2 11.3 16.9 *0.7 8.5 22.7 44.7

Inguinal hernia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 550 18.4 34.2 3.5 13.8 12.9 22.5 39.6

Noninfectious enteritis and colitis ........................... 555–558 7.6 6.7 8.4 * 7.0 12.1 14.8

Diverticula of intestine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 562 12.3 10.8 13.8 * 1.2 17.9 64.4

Cholelithiasis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 574 6.8 2.8 10.6 * 7.1 11.1 10.5

Diseases of the genitourinary system .......................... 580–629 90.2 54.8 123.5 22.2 88.7 134.4 145.0

Calculus of kidney and ureter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 592 6.3 7.6 5.1 * 6.0 11.7 9.9

Hematuria........................................... 599.7 4.4 5.7 3.2 * 2.0 7.6 14.3

Benign mammary dysplasias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 610 6.8 * 13.1 * 6.1 14.3 8.9

Lump or mass in breast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 611.72 9.0 *0.4 17.1 * 8.1 17.1 15.2

Disorders of menstruation and other abnormal vaginal bleeding.... 626,627.0–627.1 10.4 . . . 20.2 * 12.0 20.5 7.0

Complications of pregnancy, childbirth, and the puerperium............. 630–676 9.0 . . . 17.6 * 19.7 * . . .

Abortion and ectopic and molar pregnancy .................... 630–639 7.8 . . . 15.2 * 17.0 * . . .

Diseases of the skin and subcutaneous tissue..................... 680–709 18.4 17.8 18.9 5.9 17.6 25.0 32.7

Sebaceous cyst ....................................... 706.2 5.0 5.4 4.7 * 4.8 7.9 7.4

Diseases of the musculoskeletal system and connective tissue .......... 710–739 65.4 58.7 71.8 7.5 65.7 110.1 95.7

Arthropathies and related disorders .......................... 710–719 18.3 20.2 16.6 1.7 20.4 29.1 23.3

Internal derangement of knee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 717 7.2 8.8 5.6 * 9.7 9.5 5.9

Intervertebral disc disorders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 722 4.4 4.7 4.1 – 4.9 * 5.7

Lumbago ........................................... 724.2 4.3 3.8 4.8 * 3.3 7.3 10.6

Rheumatism, excluding back .............................. 725–729 21.9 17.7 25.8 2.7 22.4 39.4 26.3

Acquired deformities of toe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 735 5.3 1.6 8.7 * 3.8 10.9 10.1

Congenital anomalies .................................... 740–759 8.8 9.1 8.4 16.8 5.4 4.7 13.0

Symptoms, signs, and ill-defined conditions ...................... 780–799 39.0 32.9 44.8 9.8 27.6 62.2 94.7

Abdominal pain ........................................ 789.0 5.3 3.7 6.7 * 4.8 7.2 11.0

Injury and poisoning .................................... 800–999 45.8 55.2 37.0 21.9 49.1 59.2 55.3

Fractures .......................................... 800–829 10.7 13.4 8.2 11.1 12.6 8.1 7.3

Current tear of medial cartilage or meniscus of knee ................. 836.0 8.7 11.9 5.6 * 9.7 15.4 8.8

Supplementary classification ................................V01–V82 41.2 31.9 50.1 9.1 45.2 43.5 79.2

Visit for sterilization ......................................V25.2 12.8 3.8 21.3 * 27.2 * –

Diseases of the blood and blood-forming organs, mental disorders, and certain

conditions originating in the perinatal period ......... 280–289,290–319,760–779 4.7 3.9 5.5 * 2.1 6.5 16.2

* Figure does not meet standard of reliability or precision.

. . . Category not applicable.

– Quantity zero.

Advance Data No. 283 + March 14, 1997 11
Table 10. Relative standard errors for number and rate of ambulatory surgery visits by first-listed diagnoses, sex, and age:

United States, 1994

[Diagnostic categories and code numbers are based on the International Classification of Diseases, 9th Revision, Clinical Modification (ICD–9–CM)]

Category of first-listed diagnosis

and ICD–9–CM code Total

Sex Age

Male Female

Under

15 years

15–44

years

45–64

years

65 years

and over

Standard error as a percent of the number or rate of visits

All conditions .............................................. 4.28 4.43 4.28 5.21 4.48 4.68 5.01

Infectious and parasitic diseases ............................. 001–139 7.41 9.93 11.04 20.49 8.84 21.84 25.91

Neoplasms........................................... 140–239 5.50 6.30 5.56 8.34 6.45 6.37 6.38

Malignant neoplasms ............................. 140–208,230–234 5.60 6.92 5.53 19.38 7.90 6.62 6.74

Malignant neoplasm of skin...................... 172–173,176.0,198.2 7.99 9.40 9.21 . . . 16.41 10.71 9.66

Malignant neoplasm of breast ....................... 174–175,198.81 7.78 . . . 7.55 . . . 14.48 11.40 11.07

Benign neoplasms..................................... 210–229 7.02 8.31 7.03 9.36 7.76 8.51 9.02

Benign neoplasm of colon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211.3 9.80 10.70 9.62 . . . 13.40 10.49 10.46

Lipoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 9.52 13.19 12.22 . . . 15.65 13.34 16.34

Endocrine, nutritional and metabolic diseases, and immunity disorders...... 240–279 9.06 12.87 10.57 . . . 14.28 11.80 14.34

Diseases of the nervous system and sense organs.................. 320–389 4.79 4.88 4.95 5.74 6.20 5.39 6.06

Carpal tunnel syndrome ................................... 354.0 5.94 7.49 6.37 . . . 7.72 7.21 9.29

Glaucoma . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365 13.61 14.86 14.94 . . . 23.91 19.14 14.08

Cataract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 366 6.54 6.83 6.71 26.87 11.85 7.85 6.56

Otitis media and Eustachian tube disorders ..................... 381–382 6.13 6.73 6.53 6.25 16.02 22.61 . . .

Diseases of the circulatory system ............................ 390–459 9.04 9.10 9.78 . . . 8.70 11.04 10.56

Heart disease ............... 391–392.0,393–398,402,404,410–416,420–429 14.93 14.19 17.98 . . . 18.97 18.10 14.87

Hemorrhoids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455 9.22 10.49 10.21 . . . 10.69 10.79 12.81

Diseases of the respiratory system ............................ 460–519 5.97 6.56 6.44 6.55 6.64 9.32 10.27

Deviated nasal septum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 470 8.15 10.23 10.14 20.06 8.52 13.26 . . .

Chronic sinusitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 473 9.45 12.92 11.00 16.53 10.80 13.52 20.86

Chronic disease of tonsils and adenoids . . . . . . . . . . . . . . . . . . . . . . . . . . 474 7.02 7.55 8.53 7.10 9.13 . . . . . .

Diseases of the digestive system ............................. 520–579 5.97 5.44 6.89 9.13 5.71 6.62 7.73

Diseases of teeth and supporting structures ..................... 520–525 14.87 15.27 16.78 18.77 22.39 22.65 . . .

Diseases of esophagus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 530 11.84 12.46 12.21 25.69 12.79 11.69 14.07

Ulcer of stomach and small intestine ......................... 531–534 9.68 11.41 11.17 . . . 15.26 15.36 12.66

Gastritis and duodenitis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 535 10.61 11.17 11.31 29.18 11.46 13.51 12.88

Inguinal hernia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 550 4.50 4.69 9.75 9.25 6.36 7.28 7.39

Noninfectious enteritis and colitis ........................... 555–558 9.36 12.29 8.94 . . . 9.79 12.85 15.63

Diverticula of intestine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 562 10.37 11.57 10.91 . . . 21.17 12.45 10.62

Cholelithiasis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 574 7.84 14.02 7.94 . . . 9.89 9.58 12.97

Diseases of the genitourinary system .......................... 580–629 5.62 7.34 5.46 10.34 5.49 6.02 8.65

Calculus of kidney and ureter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 592 11.98 12.51 14.04 . . . 15.14 13.39 15.10

Hematuria............................................ 599.7 14.45 13.57 19.19 . . . 22.94 15.57 17.39

Benign mammary dysplasias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 610 11.66 . . . 11.69 . . . 14.35 11.83 13.47

Lump or mass in breast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 611.72 10.60 29.37 10.69 . . . 11.59 12.19 13.66

Disorders of menstruation and other abnormal vaginal bleeding.... 626,627.0–627.1 6.61 . . . 6.61 . . . 8.47 8.05 14.51

Complications of pregnancy, childbirth, and the puerperium............. 630–676 8.66 . . . 8.66 . . . 8.67 . . . . . .

Abortion and ectopic and molar pregnancy ..................... 630–639 9.16 . . . 9.16 . . . 9.18 . . . . . .

Diseases of the skin and subcutaneous tissue..................... 680–709 7.96 9.16 8.13 15.57 8.69 9.17 11.63

Sebaceous cyst ........................................ 706.2 12.41 13.15 14.96 . . . 12.24 14.52 14.66

Diseases of the musculoskeletal system and connective tissue .......... 710–739 6.23 6.28 6.56 11.99 6.30 7.58 7.29

Arthropathies and related disorders .......................... 710–719 6.40 6.40 7.90 21.92 7.23 7.89 10.64

Internal derangement of knee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 717 7.45 8.10 9.41 . . . 8.58 9.31 17.28

Intervertebral disc disorders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 722 22.81 23.71 23.52 . . . 23.40 . . . 22.12

Lumbago ............................................ 724.2 13.74 14.30 14.97 . . . 16.63 15.30 13.97

Rheumatism, excluding back .............................. 725–729 5.53 6.85 6.69 14.32 6.26 7.55 9.25

Acquired deformities of toe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 735 8.15 12.88 8.56 . . . 11.94 9.55 12.57

Congenital anomalies .................................... 740–759 8.16 8.82 9.97 11.69 12.09 15.49 15.73

Symptoms, signs, and ill-defined conditions ...................... 780–799 13.49 12.88 14.14 16.05 15.30 13.61 13.29

Abdominal pain ........................................ 789.0 12.13 15.76 11.89 . . . 13.44 15.35 19.19

Injury and poisoning ..................................... 800–999 5.95 6.40 6.48 8.04 7.32 6.40 7.13

Fractures .......................................... 800–829 6.77 7.51 8.20 10.58 8.44 9.43 13.15

Current tear of medial cartilage or meniscus of knee ................. 836.0 8.85 8.66 11.17 . . . 9.67 10.45 16.14

Supplementary classification ................................V01–V82 10.59 13.83 9.37 25.28 8.03 13.08 15.50

Visit for sterilization ......................................V25.2 7.36 16.07 7.78 . . . 7.27 . . . . . .

Diseases of the blood and blood-forming organs, mental disorders, and certain

conditions originating in the perinatal period ......... 280–289,290–319,760–779 12.96 13.57 16.47 . . . 17.46 16.97 14.84

. . . Category not applicable.

NOTE: The standard error of a number or rate in tables 8 or 9 can be obtained by multiplying the estimate by the corresponding relative standard error, shown as a percent, in this table.

12 Advance Data No. 283 + March 14, 1997
Figure 5. Medical abstract for the National Survey of Ambulatory Surgery, 1994.

Advance Data No. 283 + March 14, 1997 13
Figure 5. Medical abstract for the National Survey of Ambulatory Surgery, 1994—Con.

14 Advance Data No. 283 + March 14, 1997
with rates or percents calculated from

rounded data.

The population estimates used in

computing rates are for the U.S. civilian

population, including institutionalized

persons, as of July 1, 1994. These

estimates were provided by the U.S.

Bureau of the Census and are consistent

with population estimates published in

Current Population Reports.

Tests of significance

In this report, statistical inference is

based on the two-sidedt-test with a

critical value of 1.96 (0.05 level of

significance). Terms such as ‘‘higher’’

and ‘‘less’’ indicate that differences are

statistically significant. Terms such as

‘‘similar’’ or ‘‘no difference’’ mean that

no statistically significant difference

exits between the estimates being

compared. A lack of comment on the

difference between any two estimates

does not mean that the difference was

tested and found not to be significant.

References

1. New surgical technologies reshape

hospital strategies. Hospitals

66(9):30–36, 38, 40–42. 1992.

2. Leader S, Moon M. Medicare trends

in ambulatory surgery. Health Affairs

Spring: 158–170. 1989.

3. Durant G. Ambulatory surgery

centers: surviving, thriving into the

1990’s. Medical Group Management

Journal 36(2): 16–18, 20. 1989.

4. SMG Marketing Group, Inc.

Outpatient surgery centers exceed 3

million cases. SMG Market Letter

8(5). 1994.

5. Graves EJ and Gillum BS. 1994

summary: National Hospital

Discharge Survey. Advance data from

vital and health statistics; no 278.

Hyattsville, Maryland: National

Center for Health Statistics. 1996.

6. Schappert SM. National Ambulatory

Medical Care Survey: 1994

summary. Advance data from vital

and health statistics; no 273.

Hyattsville, Maryland: National

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7. Lipkind KL. National Hospital

Ambulatory Medical Care Survey:

1994, outpatient department survey.

Advance data from vital and health

statistics; no 276. Hyattsville,

Maryland: National Center for Health

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summary. Advance data from vital

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Hyattsville, Maryland: National

Center for Health Statistics. 1996.

9. SMG Marketing Group, Inc. Hospital

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Healthcare Information Specialists.

April 1993.

10. SMG Marketing Group, Inc.

Freestanding Outpatient Surgery

Centers Database. Chicago:

Healthcare Information Specialists.

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11. Health Care Financing

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Public Use File. Baltimore: 1993.

12. Massey JT, Moore TF, Parsons VL,

Tadros W. Design and estimation for

the National Health Interview

Survey, 1985–94. National Center for

Health Statistics. Vital Health Stat 2

(110). 1989.

13. Public Health Service and Health

Care Financing Administration.

International Classification of

Diseases, 9th Revision, Clinical

Modification. Washington: Public

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14. Shah BV, Barnwell BG, Bieler GS.

SUDAAN User’s Manual: Software

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Release 6.40. Research Triangle

Park, NC: Research Triangle

Institute. 1995.

Advance Data No. 283+ March 14, 1997 15
Suggested citation

Kozak LJ, Hall MJ, Pokras R, Lawrence L.

Ambulatory surgery in the United States,

1994. Advance data from vital and health

statistics; no 283. Hyattsville, Maryland:

National Center for Health Statistics. 1997.

Copyright information

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public domain and may be reproduced or

copied without permission; citation as to

source, however, is appreciated.

National Center for Health Statistics

Director

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Deputy Director

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Centers for Disease Control and Prevention

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