3-11: Antibiotic Prophylaxis of Surgical Site Infections

Surgical site infection is estimated to occur in roughly 4% of general or vascular operations. Although the type of procedure is the main factor determining the risk of developing a surgical site infection, certain patient factors have been associated with increased risk, including diabetes mellitus, older age, obesity, smoking, heavy alcohol consumption, admission from a long-term care facility, and multiple medical comorbidities. For most major procedures, the use of prophylactic antibiotics has been demonstrated to reduce the incidence of surgical site infections. Substantial evidence suggests that a single dose of an appropriate intravenous antibiotic—or combination of antibiotics—administered 30–60 minutes prior to skin incision is as effective as multiple-dose regimens that extend into the postoperative period. For most procedures, a first-generation cephalosporin (eg, cefazolin 2 g intravenously) is as effective as later-generation agents.

Other strategies to prevent surgical site infections have proven to be controversial. In several studies of patients with nasal colonization by Staphylococcus aureus, treatment with 2% mupirocin ointment (twice daily for 3 days) before surgery reduced the risk of surgical site infection by this organism. However, the ideal strategy for detecting and treating nasal colonization remains uncertain. High-concentration oxygen delivered in the immediate postoperative period may reduce surgical site infections in patients undergoing colorectal surgery or operations requiring general anesthesia. The use of razors for hair removal actually seems to increase the risk of surgical site infections and is therefore specifically not recommended. If preoperative hair removal is indicated, the use of clippers is preferred.

Guidelines for antibiotic prophylaxis against infective endocarditis in patients undergoing invasive procedures are presented in Chapter 33. Given the lack of evidence for antibiotic prophylaxis against prosthetic joint infection before dental procedures, guidelines from the American Academy of Orthopedic Surgeons and the American Dental Association recommend against this practice.