Postoperative antimicrobial prophylaxis following spinal decompression surgery: is it necessary?

Abstract

Antimicrobial prophylaxis (AMP) can reduce the risk of surgical-site infection (SSI) following many types of surgery, particularly spinal surgery. After publication of the Guideline for Prevention of Surgical Site Infection by the Centers for Disease Control and Prevention in 1999, a large number of studies confirmed the effectiveness of AMP. However, because the concept of AMP is not clear in Japan, the duration of postoperative AMP tends to be long. The purpose of this study was to compare the infection rates following spinal surgery for postoperative AMP versus no postoperative AMP. The study comprised 284 patients who underwent spinal surgery without instrumentation at our hospital from October 2003 to August 2009. The patients were divided into two groups based on the method of AMP administration: a postoperative dose group and a no postoperative dose group. SSI incidences were calculated for the two groups. The incidence of SSI was 2.1% (6/284) overall and 2. 8% (4/141) vs. 1.4% (2/143) for the postoperative dose and no postoperative dose groups, respectively. The infection rate difference between the two groups was not significant. The incidence of SSI showed a downward trend as the frequency of antibiotics decreased. Two cases of pseudomembranous colitis, both in the postoperative dose group, were the only complications of the antibiotics. AMP duration was not related to the SSI rate. SSIs trended lower in the no postoperative dose group compared with the postoperative dose group. Postoperative administration of AMP appears to be unnecessary for spinal decompression surgery without instrumentation.