Biliary tract surgery.

Postoperative wound infection rates after biliary tract surgery vary tremendously from 2% after uncomplicated cholecystectomy to 20% in series including many jaundiced patients. Almost all such infections arise from organisms growing in the diseased biliary tract, since infection rate of 1% are achieved when the bile is sterile. A history of cholangitis identifies only one third of the patients with infected bile, but four easily recognized clinical factors point to positive bile cultures in 60% to 75% of patients: (1) age over 70, (2) obstructive jaundice, (3) common duct stones without jaundice, and (4) emergent acute cholecystitis. These selected high-risk patients have postoperative infection rates of 20% to 27%. Preoperative administration of cephaloridine reduced this high rate of infection to 5% in a prospective randomized but not blinded trial. The initially reported experience of 84 patients has been extended to 140 and continues to confirm the efficacy of prophylactic antibiotics in selected high-risk patients. In contrast, there is no present evidence supporting the use of antibiotic prophylaxis in low-risk patients under 70 years of age undergoing uncomplicated cholecystectomy.