New Guidelines for Antimicrobial Prophylaxis in Surgery

Abstract

This is an updated set of guidelines for antimicrobial prophylaxis in surgery developed jointly by the American Society of Health-System Pharmacists, the Infectious Diseases Society of America, the Surgical Infection Society, and the Society for Healthcare Epidemiology of America. Key updates include more specific recommendations for optimal timing, dosing, redosing, and duration of antimicrobial therapy.

These guidelines were developed jointly by the American Society of Health-System Pharmacists, the Infectious Diseases Society of America, the Surgical Infection Society, and the Society for Healthcare Epidemiology of America and are an update of previous guidelines.¹ Key updates include:

• Preoperative-dose timing: The optimal time for administration is within 60 minutes before incision; this is a more specific time than the prior recommendation of administration at induction of anesthesia. For vancomycin, which requires a long administration time (1–2 hours), the dose should begin within 120 minutes before the incision.
• New information is included regarding weight-based dosing; this includes a higher dose of cefazolin for persons weighing more than 120 kg.
• New recommendations are given for a shortened postoperative course. Most cases can be treated with a single dose. The duration should be less than 24 hours regardless if there are indwelling drains.
• Redosing: If the duration of the surgery exceeds 2 half-lives of the antimicrobial or there is excessive blood loss, intraoperative redosing is needed to ensure adequate serum and tissue concentrations of the antimicrobial.

Specific recommendations for doses, redosing intervals, and preferred agents for selected antimicrobials and surgical procedures are listed in Tables 1 and 2. Of note, vancomycin is not recommended as a preferred choice for any procedure. The guideline suggests that vancomycin may be included when a cluster of postoperative methicillin-resistant Staphylococcus aureus (MRSA) have been detected at an institution and should be considered for patients with known or high risk for MRSA colonization. The guideline panel points out that vancomycin is less effective than cefazolin for preventing postoperative infections caused by methicillin-susceptible S aureus; thus, vancomycin is used in combination with cefazolin at some institutions.

TABLE 1: Recommended Doses and Redosing Interval for Surgical Prophylaxis

TABLE 2: Recommendations for Antimicrobial Agents for Selected Surgical Procedures

The guideline panel also evaluated the prophylactic use of mupirocin. The strongest recommendations were for cardiac patients (“should be given intranasally to all patients with documented S aureus colonization”) and orthopedic procedures (“preoperative decolonization with intranasal mupirocin may have utility in patients undergoing elective orthopedic procedures who are known to be colonized or infected with either MRSA or methicillin-susceptible S aureus”).

An additional concern raised within the guideline is the potential association of surgical prophylaxis with Clostridium difficile–associated colitis. Risk factors include longer duration of prophylaxis and use of multiple antimicrobial agents. Limiting the duration of antimicrobial prophylaxis to a single preoperative dose can reduce the risk of C difficile disease.