Efficacy of Cefazolin, Cefamandole, and Gentamicin as Prophylactic Agents in Cardiac Surgery

Abstract

In an effort to develop an improved regimen of antibiotic prophylaxis in cardiac surgery, 1030 patients who were to have elective cardiothoracic surgery involving a median sternotomy were selected at random to receive cefamandole or cefazolin, with or without gentamicin, in a prospective double-blind study. Cefazolin was significantly less effective than cefamandole at both the sternal (1.8% vs. 0.4%, respectively, p < 0.05) and donor sites (1.3% vs. 0%, respectively, p < 0.02). Seven Staphylococcus aureus infections occurred among cefazolin recipients as compared with no such infections among the patients receiving cefamandole (p < 0.01). All five wound infections yielding fungi or gentamicin-resistant gram-negative rods occurred in patients who had received gentamicin as a second prophylactic agent. These data suggest that gentamicin has no role as a prophylactic antibiotic in cardiac surgery and that, compared with cefamandole, cefazolin offers unreliable prophylaxis against deep infection at both the sternal and donor sites.