Efficacy data for single-dose cefazolin prophylaxis at hysterectomy are meager, and there are none evaluating the impact of route of administration on efficacy. For these reasons, 772 women undergoing elective abdominal or vaginal hysterectomy for benign diseases were given 1 g cefazolin either intramuscularly or intravenously in a randomized clinical trial. Preoperative diagnoses and clinical, surgical, and outcome variables were similar by route of administration for each surgical approach. Risk factors for infection after abdominal hysterectomy included younger age, lower postoperative hemoglobin concentration, and pelvic hematoma; women who developed infection after vaginal hysterectomy were heavier than those who remained uninfected and were more likely to have a pelvic hematoma. The overall incidence of major operative site infection requiring parenteral antimicrobial therapy in evaluable women was 7.2%: 7.6% for 539 women undergoing abdominal hysterectomy and 6.3% for 207 women undergoing vaginal hysterectomy. Postoperative infection was unrelated to route of cefazolin administration.
(C) 1990 The American College of Obstetricians and Gynecologists