Intravenous prophylactic antimicrobial drugs in elective colorectal operations.

In a prospective, randomized, double blind study of 123 patients undergoing elective colorectal surgery, 61 received intravenously erythromycin gluceptate, and 62 received intravenously metronidazole perioperatively together with tobramycin. Three dosages of each drug were given. Eight patients in each treatment group had wound infections. Of these, only three in each treatment group were severe enough to require antibiotic therapy and to cause prolongation of hospitalization. Antibiotic levels in the serums of patients, in skin samples and in intestinal walls showed that metronidazole was most frequently detected at satisfactory concentrations in serum and that skin and the intestinal wall did not contain any detectable antibiotic.