Prophylaxis in gynaecological and obstetric surgery: a comparative randomised multicentre study of single-dose cefotetan versus two doses of cefazolin.

Antimicrobial prophylaxis is recommended in all clean-contaminated surgery where the critical threshold of number and virulence of the contaminating organisms with respect to host resistance is reached. Obstetric and gynaecological surgery is clean-contaminated and risk of infection due to aerobic and anaerobic bacteria without prophylaxis can be quantified at 30-40% for vaginal hysterectomy, 10-35% for abdominal hysterectomy and 10-34% for caesarean section. To assess the role of two different cephalosporins as short term prophylaxis, we carried out a multicentre randomised study involving a single 2 g i.v. dose of cefotetan in comparison with two doses of cefazolin (2 g i.v. before surgery and after 8 hours). Criteria for exclusion were: exposure to antibiotics within 7 days, preoperative infection, hypersensitivity to beta-lactams. Four hundred and sixty patients entered the study, of which 229 received cefotetan and 231 cefazolin. No significant differences in mean age, obesity, preoperative weight loss, diabetes, type of disease, type of surgery (vaginal or abdominal hysterectomies and caesarean sections) and number of pregnancies and abortions existed between the two groups of patients. The total rate of infected patients undergoing hysterectomy was 8.6% (13/151) in the cefotetan group and 17.4% (29/167) in the cefazolin group (p less than 0.05). This difference was due to cases of symptomatic bacteriuria and antibiotic retreatment, while wound infections were not significantly different (2.6% and 1.8% respectively). Among patients undergoing caesarean section, 9 of 78 (11.5%) and 7 of 64 (10.9%) were infected following cefotetan and cefazolin, respectively (not significant). Cefotetan mean tissue concentrations in gynaecological organs were higher than those of cefazolin (25.5-44.8 vs. 7.4-9.5 mg/kg).(ABSTRACT TRUNCATED AT 250 WORDS)