Should antibiotic prophylaxis be used routinely in clean surgical procedures: A tentative yes

Background. The incidence of surgical site infection (SSI) after clean surgical procedure has traditionally been regarded as too low for routine antibiotic prophylaxis. But we now know that host factors may increase the risk of SSI to as high as 20%. We assessed the value of prophylactic cefotaxime in patients stratified for risk of SSI in a aandomized double-blind trial. Methods. Patients admitted for clean elective operations were enrolled, stratified for risk by National Nosocomial Infection Survey criteria, and randomized to receive intravenous cefotaxime 2 gm or placebo on call for operation. They were followed for 4 to 6 weeks for SSI diagnosed by Centers for Disease Control and Prevention criteria. Result. Analysis of 775 patients showed that the 378 evaluable patients who received cefotaxime had 70% fewer SSIs than those who did not—Mantel-Haenszel risk ratio (MH-RR) 0.31; 95% confidence intervals (CI) 0.11 to 0.83. Benefit was clear in the 616 low risk patients—0.97% versus 3.9% SSI (MH-RR 0.25, CI 0.07 to 0.87, p=0.018), but only a trend was seen in 136 high risk patients—2.8% versus 6.1% SSI (MH-RR 0.48, CI 0.09 to 2.5). Conclusions. The results indicate clear benefit for routine antibiotic prophylaxis in clean surgical procedures. High risk patients need more study.