Metronidazole and ticarcillin in the prevention of sepsis after appendicectomy.

Ticarcillin was compared with metronidazole in the prevention of wound infection after appendicectomy. Two hundred nine patients with a diagnosis of acute appendicitis were admitted to a prospective, randomized study and received 500 mg of metronidazole or 5 g of ticarcillin intravenously before operation. Those patients with gangrenous or perforated appendices received two additional doses of the trial drug at 8 hourly intervals. The overall incidence of wound infections in both the metronidazole and the ticarcillin groups was 9 percent. There were no intraabdominal abscesses. Metronidazole abolished anaerobic wound infections. All the early wound infections (between 2 and 4 days after operation) occurred in patients with gangrenous or perforated appendices. We conclude that ticarcillin is as effective as metronidazole in the prevention of wound infection after appendicectomy, but in high-risk patients, (those with gangrenous or perforated appendices) longer courses of antibiotics should be employed.