Infection following coronary artery surgery. Comparison of two antibiotic prophylaxis regimens.

A prospective randomized study was conducted in 200 patients undergoing coronary artery bypass surgery. All patients received intravenous (IV) cephalothin prophylaxis for 48 hours beginning with anesthetic induction. Group A (99 eligible patients) received cephalexin 500 mg po, qid for three extra days. Group B (94 eligible patients) received no oral therapy. The overall infection rate was 9.3 percent (18 patients). Six patients had multiple sites of involvement. There was no difference between group A (9.0 percent, nine patients) vs B (9.5 percent, nine patients) (p greater than 0.5). The median sternotomy infection rate, superficial or deep, was 2.6% (five patients). The surgical wound infection rate was 4.7 percent (nine patients). The overall infection rate compares favorably with that of high risk groups for clean surgical procedures defined in SENIC study. There was no advantage to prolonged oral cephalexin prophylaxis following coronary artery bypass (CAB) surgery.