Single dose cefazolin plus metronidazole versus existing multi-dose regimen for prophylaxis in caesarean section.

Sir,

The role of surgical chemoprophylaxis in caesarean section is well established,[1] but the recommendations about single-dose prophylaxis are not uniformly followed. Given the ever-increasing economic and health burden of caesarean deliveries in India[2] and the need for convenient and less costly regimens, this study was undertaken to compare the efficacy and estimate cost of prophylaxis with a single dose of cefazolin plus metronidazole and conventional multi-dose regimen for prophylaxis in caesarean section.

This prospective, open, randomized trial was conducted in our institution after approval by Institutional Ethics Committee. A total of 194 women with at least 28 weeks of gestation with singleton pregnancy undergoing caesarean delivery for various indications (during September–December 2006) were randomized after obtaining informed consent to receive either a single dose of cefazolin 1 g plus metronidazole 500 mg intravenously at cord clamping or ciprofloxacin 200 mg 12 hourly plus metronidazole 500 mg 8 hourly intravenously for the first 24 hours and, subsequently, ciprofloxacin 500 mg 12 hourly plus metronidazole 400 mg eight hourly, orally for the next six days. Women with a rupture of membranes for six or more hours, fever of 38°C or more at the time of caesarean section and suspected allergy to any of the study drugs were excluded.

Postoperative infectious morbidity in terms of wound infection, febrile morbidity, and endometritis was evaluated according to the method described by Pitt et al.[3] The total cost of antibiotic prophylaxis per patient was calculated by using the prices listed in IDR Triple I pharmacy compendium (Nov-Dec 2006). Statistical analysis was done by Chi-square test and Z test. P<0.05 was considered significant.

Two groups were comparable with respect to demographic and other baseline characteristics [Table 1]. Six percent of patients in the multi-dose group developed post-caesarean infectious morbidity as compared to four percent in the single-dose group [Table 2]. The most common infection was wound infection. One patient from the multi-dose group developed pelvic abscess—a complication of endometritis. There was no significant difference between the two treatment groups with respect to postoperative infectious morbidity, length of hospital stay, or adverse drug effects. Only minor suspected adverse drug effects such as nausea, headache, and dizziness were reported by four percent of women in the multi-dose group and one percent of women in the single-dose group. Depending on the price of the cheapest and the most expensive brand, the range of approximate cost of antibiotic prophylaxis per patient for the single-dose group was Rs 50-100 and that for the multi-dose group was Rs 116-407.

Table 1

Demographic and other baseline characteristics

Table 2

Post-caesarean infectious morbidity

The present study shows that prophylaxis with a single dose of cefazolin plus metronidazole is equivalent in efficacy to the week-long regimen of ciprofloxacin plus metronidazole in caesarean section, but it is 2-4 times less costly. Our findings are corroborated by previous studies, which show that metronidazole-containing regimens are as effective as week-long regimens, but come only at one-tenth of the cost.[45]