Ceftriaxone is more effective than gentamicin/metronidazole prophylaxis in reducing wound and urinary tract infections after bowel operations. Results of a controlled, randomized, blind clinical trial.

A controlled, randomized trial with blind assessment of end points is described comparing ceftriaxone (1 g) given at induction of anesthesia with gentamicin (2 mg/kg) and metronidazole (500 mg) (GM), three times, every eight hours starting at induction, in preventing wound, chest, and urinary tract infections following bowel operations. Patients with inflammatory bowel disease received prophylaxis for five days. Two hundred sixty patients were randomized, and 196 were studied after exclusions. Ninety-four were given ceftriaxone, and 102 were given GM. Chest infection was defined as pyrexia plus clinical or radiologic signs of consolidation or the production of purulent sputum. Wound infection was diagnosed on the basis of purulent wound discharge or pyrexia plus swelling, redness, and pain around the wound, and urinary tract infection was diagnosed from microbiologic results. There was a significant reduction in wound infection (17 percent to 6 percent; P < 0.05) and in urinary tract infection (8 percent to 1 percent; P < 0.05) in the ceftriaxone group compared with the GM group. Chest infection occurred in 16 percent of the ceftriaxone group compared with 25 percent of the GM group, but this difference was not statistically significant. Infected patients were in the hospital more than four days longer than uninfected patients, a statistically significant difference (P < 0.01). It is concluded that ceftriaxone is superior to GM in reducing postoperative sepsis and that this effect is likely to be due to the sustained bactericidal blood levels achieved by ceftriaxone.