Cephalothin Prophylaxis and valve replacement.

In a study of antibiotic prophylaxis in adults undergoing heart valve replacement, we found that a 2 gm dose of cephalothin given intraoperatively produced adequate antimicrobial activity in the bloodstream throughout the period of cardiopulmonary bypass. A dosage of 1 gm every four hours postoperatively did not lead to significant accumulation of the antibiotic. With prophylaxis restricted to the intraoperative and early postoperative period, adverse drug reactions and superinfections were not a problem. Further, no cases of prosthetic valvulitis were encountered.