Background: National guidelines recommend that surgical prophylactic antimicrobials be initiated within 1 hour prior to incision and discontinued 24 hours postoperatively. However, the risks and benefits of longer duration of antimicrobials are uncertain.
Study design: Retrospective cohort study.
Setting: Veterans Affairs hospitals.
Synopsis: After stratification by type of surgery and adjustment for covariates, antibiotic prophylaxis greater than 24 hours was not associated with lower SSI risk.
However, the odds of postoperative AKI increased with each additional day of prophylaxis (adjusted odds ratios, 1.82; 95% confidence interval,1.54-2.16 and aOR, 1.79; 95% CI, 1.27-2.53) with longer than 72 hours prophylaxis for cardiac and noncardiac surgery, respectively). Similarly, C. difficile infections increased with each additional day beyond 24 hours (aOR, 3.65; 95% CI, 2.40-5.55 with more than 72 hours of use).
Bottom line: Each day of perioperative antimicrobial prophylaxis beyond 24 hours increases the risk for postoperative AKI or C. difficile infection without reducing the risk of surgical site infection.
Citation: Branch-Elliman W et al. Association of duration and type of surgical prophylaxis with antimicrobial-associated adverse events. JAMA Surg. 2019 Apr 24..
Dr. Miller is a hospitalist at the University of Colorado at Denver, Aurora.