Clinical Consequences and Cost of Limiting Use of Vancomycin for Perioperative Prophylaxis: Example of Coronary Artery Bypass Surgery

Abstract

Routine use of vancomycin for perioperative prophylaxis is discouraged, principally to minimize microbial resistance to it. However, outcomes and costs of this recommendation have not been assessed. We used decisionanalytic models to compare clinical results and cost-effectiveness of no prophylaxis, cefazolin, and vancomycin, in coronary artery bypass graft surgery. In the base case, vancomycin resulted in 7% fewer surgical site infections and 1% lower all-cause mortality and saved $117 per procedure, compared with cefazolin. Cefazolin, in turn, resulted in substantially fewer infections and deaths and lower costs than no prophylaxis. We conclude that perioperative antibiotic prophylaxis with vancomycin is usually more effective and less expensive than cefazolin. Data on vancomycin's impact on resistance are needed to quantify the trade-off between individual patients' improved clinical outcomes and lower costs and the future longterm consequences to society.The emergence of vancomycin-resistant enterococci has opened a new era of hardly treatable bacterial infections, and there is now evidence that more virulent common pathogens such as Staphylococcus aureus can also develop resistance to vancomycin (1,2). The use of vancomycin is hypothesized to promote the development or transmission of this resistance (3,4). Restrictive guidelines have therefore been disseminated for the use of vancomycin or teicoplanin, another glycopeptide agent (5). These guidelines include a recommendation against the routine use of vancomycin as perioperative antibiotic prophylaxis for surgical site infections.However, vancomycin is preferred for preventing infections caused by methicillin-resistant Staphylococcus aureus (MRSA) or methicillin-resistant coagulase-negative staphylococci. This is the rationale for recommending vancomycin prophylaxis when the risk for infection from methicillinresistant pathogens is high (6-11), although no guideline has made a clear statement on when to use this alternative. Since antibiotics are commonly used for prophylaxis, liberal interpretation of the prophylaxis guidelines will clearly jeopardize efforts to limit the use of vancomycin. Vancomycin is also more expensive to purchase and administer than cephalosporins.To inform both the clinical and public policy debate with respect to the optimal prophylaxis regimen, we conducted a cost-effectiveness analysis to compare the short-and longterm consequences of using vancomycin and cefazolin as first-line perioperative prophylaxis. We focused on patients who underwent coronary artery bypass graft surgery (CABG) because this is a large, relatively homogeneous population with substantial risk for serious surgical site infection (12,13). Methods Cost-Effectiveness AnalysisWe developed a decision-analytic model (Figure 1) to calculate the clinical benefits and costs associated with alternative strategies for antibiotic prophylaxis in a hypothetical cohort of 10,000 patients undergoing CAGB surgery. The three strategies evaluated were 1) no prophylaxis; 2) rou...

Antibiotic Policies: Fighting Resistance

“…In addition, short exposures to glycopeptides for prophylaxis in non-MRSA patients are far less likely to promote resistance than prolonged treatments, especially for MRSA infections. We recently developed a decision-analytic model to calculate the clinical benefits and costs associated with the use of either cefazolin or vancomycin for prophylaxis in coronary artery bypass surgery (Zanetti et al 2001). In the base case, where 40% of S. aureus and 80% of coagulase-negative staphylococci were resistant to methicillin, cefazolin had to be 25% better than vancomycin against susceptible organisms in order to be more effective.…”

Sternal wound infections

“…10 Prolonged antimicrobial administration can be harmful to patients by promoting antimicrobial-resistant bacteria and increasing the incidence of antibiotic-associated complications. 2,14 Prophylaxis using routine vancomycin resulted in fewer deep and superficial SSIs and fewer deaths compared with routine cefazolin for CABG surgery. 2 About a third (34%) of patients undergoing cardiac surgery had their antimicrobial prophylaxis discontinued within 24 hours of completion of surgery.…”

“…12, 13 Research has found that only 70% of cardiac surgery patients received cefazolin (Ancef), and only 60% received antibiotics 1 hour or less prior to surgical incision. 14 Additional concerns regarding antimicrobial resistance were found.…”

Perioperative prophylaxis; viral transmission; surgical scrubs; iodophors; hepatitis B vaccine

“…This study assessed outcomes and costs associated with discouraging the routine use of vancomycin as a perioperative prophylaxis 1 . A cost‐effectiveness analysis using a hypothetical cohort of 10,000 patients undergoing coronary artery bypass grafting procedures was conducted.…”