Prophylaxis of post-appendicectomy sepsis by metronidazole and ampicillin: A randomized, prospective and double-blind trial

Abstract
Two hundred and eighty-three patients were admitted to a randomized, prospective and double-blind trial of the effect of the addition of ampicillin to metronidazole in the prophylaxis of post-appendicectomy wound sepsis. Nineteen out of 142 patients in the metronidazole and ampicillin group developed wound sepsis compared with 33 out of 141 patients in the metronidazole group. The difference is statistically significant. Early cases, including normal, acutely inflamed and gangrenous appendices, received 2 doses of antibiotics. In late cases with perforation and abscess formation, the antibiotics were continued for 1 week. The difference in wound infection in each of these 2 subgroups was also statistically significant. The commonest organisms isolated from the appendicular fossa and the infected wounds were Escherichia coli and Bacteroides fragilis.