A comparative study of the prophylactic effect of one dose and two dose intravenous metronidazole therapy in gynaecological surgery.

A double-blind placebo controlled trial was embarked upon to study the prophylactic effect of intravenous metronidazole in the prevention of septic complications following gynaecological surgery. Comparison was made between the effect of a single dose only, given during the operation and that of a single dose given during the operation with an additional dose given 12 h later. 270 patients took part in the trial. These patients were admitted for elective hysterectomy, abdominal or vaginal, or for repair of uterovaginal prolapse. They were randomly allocated to one of three treatment groups. In group I, each patient received 500 mg/100 ml of metronidazole i.v. given over a 20 min period at the beginning of the operation followed by a second dose of 500 mg/100 ml of metronidazole i.v. 12 h later. In group II, the procedures were the same but the second dose was 100 ml of normal saline (placebo). In group III, both doses were 100 ml of normal saline. Out of 90 patients in group I, 2 patients (2.2%) developed postoperative sepsis. 8 patients (9.0%) out of 89 in group II developed sepsis. In the placebo group (group III) 19 patients (20.9%) developed sepsis. The results clearly indicate that a two-dose i.v. metronidazole regimen is highly effective in the prevention of post-operative sepsis in gynaecological surgery.