Antibiotic prophylaxis for hernia repair.

BACKGROUND

The use of antibiotic prophylaxis for hernia repair is currently a controversial issue given the disparity among study results in this area.

OBJECTIVES

The objective of this systematic review was to clarify the effectiveness of antibiotic prophylaxis in reducing postoperative wound infection rates in elective open inguinal hernia repair.

SEARCH STRATEGY

Searches in the Cochrane Colorectal Cancer Group specialized register were conducted crossing the terms herni* and inguinal or groin and the terms antimicr* or antibiot*, as free text and MeSH terms. A similar search in Medline (WebSPIRS from Silver Platter, January/1966 to November/2002) and Embase (1976 to December/2002) were conducted using the following terms: #1 antibiotic* or antimicrob* or anti infecti* or antiinfecti*; #2 prophyla* or prevent*; #3 #1 and #2; #4 clean and (surgery or tech* or proced*); #5 herni*; #6 (wound infection) and #4; #7 #3 and (#4 or #5 or #6). Reference lists of the included studies were checked to identify additional studies.

SELECTION CRITERIA

Only randomized clinical trials were included.

DATA COLLECTION AND ANALYSIS

Seven randomized clinical trials were identified. Two of them used prosthetic material for hernia repair (hernioplasty) whereas the remaining studies did not (herniorraphy). Pooled and subgroup analysis were conducted depending on whether prosthetic material was or not used. A random effects model was used in the analysis.

MAIN RESULTS

The total number of patients included was 2660 (treatment group: 1297, control group: 1363). Overall infection rates were 3.08% and 4.69% in the prophylaxis and control groups, respectively (OR 0.61, 95%CI 0.32 - 1.17). The number of patients who need to be treated with prophylaxis (NNT) to prevent one infection in at least 30 days was 50 (95%CI 25 to infinite). The subgroup of patients with herniorrhaphy had infection rates of 3.78% and 4.87% in the prophylaxis and control groups, respectively (OR 0.84, 95%CI 0.53 - 1.34). NNT was 100 (95%CI 34 - infinite). The subgroup of patients with hernioplasty had infection rates of 1.3% and 4.2% in the prophylaxis and control groups, respectively (OR 0.28, 95%CI 0.02 - 3.14). NNT is 25 (IC95% NNH 25 to NNT 8).

REVIEWER'S CONCLUSIONS: Based on the results of this meta-analysis, there was no clear evidence that routine administration of antibiotic prophylaxis for elective inguinal hernia repair reduced infection rates.