0022-534 7/79/1216-0695$02.00/0 Vol. 121, June Printed in U.S.A.
THE JOURNAL OF UROLOGY
Copyright © 1979 by The Williams & Wilkins Co.
Review Article SYSTEMIC ANTIBIOTICS FOR PROPHYLAXIS IN UROLOGIC SURGERY: A CRITICAL REVIEW GERALD W. CHODAK
AND
MARTIN E. PLAUT*
From the Infectious Disease Service, State University of New York at Buffalo, Buffalo General Hospital, Buffalo, New York, and the Division of Urologic Surgery, Harvard Medical School and Peter Bent Brigham Hospital, Boston, Massachusetts
With justifications ranging from scientific to forensic surgeons administer antibiotics by oral and systemic routes as prophylaxis to prevent infections after many types of operative procedures. Recommendations for or against the use of prophylactic regimens often arise from data collected unscientifically. To generate recommendations based on reliable data we reviewed all studies on the use of systemic antibiotics as prophylaxis to prevent infection in patients undergoing urologic procedures, as reported in the English literature during the last quarter of a century. In a previous review of systemic prophylaxis in general surgery reports were assessed by rigid but objective criteria, an approach we also adopted in this review. 1 METHODS
We searched the English literature from 1950 through January 1978 for all studies that involved the effect of orally absorbed or systemic antibiotics given to patients with sterile urine undergoing various urologic procedures (prophylaxis). Such antibiotic trials are common for procedures such as endoscopy, transurethral surgery, open surgery of the genitourinary tract and urinary catheter insertion. The methods used in each report were reviewed. Studies were discarded if data were accumulated retrospectively, if trials were uncontrolled or weakly controlled or if patients were not assigned randomly to groups that received either antibiotic or placebo. Poorly controlled studies included those in which the type of prophylactic drug or its dose was varied once the study commenced, those in which the use of > 1 antibiotic regimen invalidated true comparative assessment and those in which substantial numbers of patients were dropped from a trial once entered into it. Burke, 2 and Alexander and Altemeie:r clearly showed that effective prophylaxis requires a therapeutic concentration of an antimicrobial agent in tissues at the time of contamination. Seventeen studies are unevaluable since prophylaxis was started after a given urologic procedure. Assorted problems invalidated another 6 reports (table 1). 4-54 Data from the remaining 13 studies have been separated according to the operation or procedure for which prophylaxis was used. All results have been analyzed statistically by the X 2 ·method or by Fisher's exact test. Tables 2 to 4 have been prepared to show the infection r-ate in groups of patients receiving placebo or antibiotic. 55--67 RESULTS
Prophylaxis for patients undergoing prostatectomy. Table 2 summarires data from 6 well designed studies of antimicrobial prophylaxis used during open and transurethral prostatecto* Requests for reprints: Buffalo General Hospital, 100 High St., Buffalo, New York 14203. 695
mies. The trials of Morris, Kudinoff and Plorde and their associates demonstrate the value of prophylaxis for transurethral prostatectomies. 56· 58· 50 Although Plorde and associates also recommend prophylaxis for open resections only the data for kanamycin are convincing. 50 In 3 reports it is concluded that prophylaxis is unnecessary during retropubic55 or transurethral57· 60 prostatectomies. The diagnosis of postoperative urinary tract infection required the presence of bacteriuria > 105 organisms per cc urine (in 4 studies) and > 104 organisms per cc urine with57 or without60 bacteria on gram-stained sediment in 2 other trials. Indwelling catheters remained for 1 to 5 days in 2 trials, 56· 60 whereas Plorde and associates used catheters for 9.4 days in patients in the control group, and 5.0 and 5.3 days in the treated patient. 59 Urinary catheters also were inserted more frequently before the operation into patients in the control group. In only 2 studies was a closed method of urinary catheter drainage used, 56· 60 whereas a semi-closed system was used in another. 59 In 3 other studies listed in table 1 the techniques of catheter insertion or care were not described. The effect of prophylaxis, if any, during an open operation on the prostate could not be evaluated because too few cases were studied. In the 253 patients from all 6 studies sepsis owing to gram-negative rods occurred in 4 patients, none of whom died. Although Osius and associates report deaths of septicemia, 57 no information exists as to the presence of sterile or infected urine in these patients before the operation. Bacteremia occurred in approximately 10 per cent of the patients, was distributed equally between control and antibiotic groups, and was of short duration. Morris and associates provided the results of prostatic cultures obtained at an operation and found that 64 per cent were positive for bacteria. 56 Only K udinoff and Gibbons and their associates reported bacteriologic methods in detail. 58 · 60 In the former study infections owing to species of Pseudomonas increased in the kanamycin treated group from 19 to 45 per cent. The incidence decreased slightly in the control group. In this same study a 6 per cent rate of antibiotic side effects was noted. The duration of antibiotic prophylaxis after an operation varied from 2 days to 5 weeks. Transurethral instrumentation. In 3 studies systemic antibiotics were evaluated for prophylaxis in transurethral instrumentation (table 3). Korbel and Maher showed a significant reduction in the incidence of postoperative bacteriuria after prophylactic use of amoxicillin or cephalexin during any of 3 transurethral procedures. 62 In contrast, neither Higgins61 nor Osius and associates57 found any benefit when antibiotics were used, although in the latter study the number of patients studied is too small for evaluation. The rate of infection in the control group of patients varied from
THE JOURNAL OF UROLOGY
Copyright © 1979 by The Williams & Wilkins Co.
Review Article SYSTEMIC ANTIBIOTICS FOR PROPHYLAXIS IN UROLOGIC SURGERY: A CRITICAL REVIEW GERALD W. CHODAK
AND
MARTIN E. PLAUT*
From the Infectious Disease Service, State University of New York at Buffalo, Buffalo General Hospital, Buffalo, New York, and the Division of Urologic Surgery, Harvard Medical School and Peter Bent Brigham Hospital, Boston, Massachusetts
With justifications ranging from scientific to forensic surgeons administer antibiotics by oral and systemic routes as prophylaxis to prevent infections after many types of operative procedures. Recommendations for or against the use of prophylactic regimens often arise from data collected unscientifically. To generate recommendations based on reliable data we reviewed all studies on the use of systemic antibiotics as prophylaxis to prevent infection in patients undergoing urologic procedures, as reported in the English literature during the last quarter of a century. In a previous review of systemic prophylaxis in general surgery reports were assessed by rigid but objective criteria, an approach we also adopted in this review. 1 METHODS
We searched the English literature from 1950 through January 1978 for all studies that involved the effect of orally absorbed or systemic antibiotics given to patients with sterile urine undergoing various urologic procedures (prophylaxis). Such antibiotic trials are common for procedures such as endoscopy, transurethral surgery, open surgery of the genitourinary tract and urinary catheter insertion. The methods used in each report were reviewed. Studies were discarded if data were accumulated retrospectively, if trials were uncontrolled or weakly controlled or if patients were not assigned randomly to groups that received either antibiotic or placebo. Poorly controlled studies included those in which the type of prophylactic drug or its dose was varied once the study commenced, those in which the use of > 1 antibiotic regimen invalidated true comparative assessment and those in which substantial numbers of patients were dropped from a trial once entered into it. Burke, 2 and Alexander and Altemeie:r clearly showed that effective prophylaxis requires a therapeutic concentration of an antimicrobial agent in tissues at the time of contamination. Seventeen studies are unevaluable since prophylaxis was started after a given urologic procedure. Assorted problems invalidated another 6 reports (table 1). 4-54 Data from the remaining 13 studies have been separated according to the operation or procedure for which prophylaxis was used. All results have been analyzed statistically by the X 2 ·method or by Fisher's exact test. Tables 2 to 4 have been prepared to show the infection r-ate in groups of patients receiving placebo or antibiotic. 55--67 RESULTS
Prophylaxis for patients undergoing prostatectomy. Table 2 summarires data from 6 well designed studies of antimicrobial prophylaxis used during open and transurethral prostatecto* Requests for reprints: Buffalo General Hospital, 100 High St., Buffalo, New York 14203. 695
mies. The trials of Morris, Kudinoff and Plorde and their associates demonstrate the value of prophylaxis for transurethral prostatectomies. 56· 58· 50 Although Plorde and associates also recommend prophylaxis for open resections only the data for kanamycin are convincing. 50 In 3 reports it is concluded that prophylaxis is unnecessary during retropubic55 or transurethral57· 60 prostatectomies. The diagnosis of postoperative urinary tract infection required the presence of bacteriuria > 105 organisms per cc urine (in 4 studies) and > 104 organisms per cc urine with57 or without60 bacteria on gram-stained sediment in 2 other trials. Indwelling catheters remained for 1 to 5 days in 2 trials, 56· 60 whereas Plorde and associates used catheters for 9.4 days in patients in the control group, and 5.0 and 5.3 days in the treated patient. 59 Urinary catheters also were inserted more frequently before the operation into patients in the control group. In only 2 studies was a closed method of urinary catheter drainage used, 56· 60 whereas a semi-closed system was used in another. 59 In 3 other studies listed in table 1 the techniques of catheter insertion or care were not described. The effect of prophylaxis, if any, during an open operation on the prostate could not be evaluated because too few cases were studied. In the 253 patients from all 6 studies sepsis owing to gram-negative rods occurred in 4 patients, none of whom died. Although Osius and associates report deaths of septicemia, 57 no information exists as to the presence of sterile or infected urine in these patients before the operation. Bacteremia occurred in approximately 10 per cent of the patients, was distributed equally between control and antibiotic groups, and was of short duration. Morris and associates provided the results of prostatic cultures obtained at an operation and found that 64 per cent were positive for bacteria. 56 Only K udinoff and Gibbons and their associates reported bacteriologic methods in detail. 58 · 60 In the former study infections owing to species of Pseudomonas increased in the kanamycin treated group from 19 to 45 per cent. The incidence decreased slightly in the control group. In this same study a 6 per cent rate of antibiotic side effects was noted. The duration of antibiotic prophylaxis after an operation varied from 2 days to 5 weeks. Transurethral instrumentation. In 3 studies systemic antibiotics were evaluated for prophylaxis in transurethral instrumentation (table 3). Korbel and Maher showed a significant reduction in the incidence of postoperative bacteriuria after prophylactic use of amoxicillin or cephalexin during any of 3 transurethral procedures. 62 In contrast, neither Higgins61 nor Osius and associates57 found any benefit when antibiotics were used, although in the latter study the number of patients studied is too small for evaluation. The rate of infection in the control group of patients varied from
