Administration of antimicrobials just prior to surgery reduces the risk of surgical site infections
Research Activities, January 2010, No. 353
A study of surgical patients at 29 hospitals found that the risk of surgical site infections (SSIs) may be reduced when patients are given antimicrobials shortly before surgery. For antimicrobials with short infusion times, administration of the drug within 30 minutes before the surgical incision reduced the infection risk by a third when compared with administration at 31 to 60 minutes before the incision (1.6 percent versus 2.4 percent risk of infection). This study followed 4,472 surgical procedures and is one of the largest studies looking at the impact of antimicrobial timing and infection risk. The authors did not recommend changing the current national standard of administering most antimicrobials within 60 minutes prior to incision based on their findings alone.
For operations lasting more than 4 hours, re-dosing antimicrobials during surgery showed a statistically insignificant trend toward reduced risk of SSIs when the preoperative dose was given at the right time (1.8 percent SSIs), but did not lower infection risk when the timing of the presurgical dose timing was not optimal (5.6 percent SSIs). The study also found that continuing antimicrobials after the completion of the operation did not have an impact on infection rates.
The hospitals that provided data were participants in a larger Trial to Reduce Antimicrobial Prophylaxis Errors. The 29 hospitals were asked to provide information on randomly selected patients who underwent cardiac surgery, hysterectomy, and surgical repair of hip and knee problems (arthroplasty). The researchers chose these types of surgery because antimicrobial prophylaxis guidelines were in place for these procedures at the beginning of the study. Infection control staff of the hospitals matched the surgical cases with their listing of previously identified SSIs. The research was funded in part by the Agency for Healthcare Research and Quality (HS11331).
More details are in "Timing of antimicrobial prophylaxis and the risk of surgical site infections," by James P. Steinberg, M.D., Barbara I. Braun, Ph.D., Walter C. Hellinger, M.D., and others in the July 2009 Annals of Surgery 250(1), pp. 10-16.