1103 Timing of adjunctive azithromycin administration for cesarean prophylaxis and the risk of post-operative infectious morbidity

Abstract

To assess whether timing of adjunctive azithromycin administration together with standard antibiotic prophylaxis is associated with risk of infectious morbidity after non-elective cesarean delivery (CD). Secondary analysis of women from the C/SOAP multicenter RCT of adjunctive azithromycin versus placebo (+ standard antibiotic prophylaxis) in women with singletons undergoing unscheduled CD. The primary exposure was timing of antibiotic administration (in 30 minute increments) relative to skin incision. The primary outcome was a post-operative infection composite of endometritis, wound infection and other maternal infections occurring within 6 weeks of CD. Outcomes were compared across antibiotic timing groups using multivariable logistic regression with >60 mins as the referent group. We also assessed potential interaction between antibiotic administration timing and randomization status. Of 2013 women from the parent RCT, 1973 patients with complete data were included: 1355 (68.7%) received any perioperative antibiotics in the 30 minutes preceding the skin incision, while 92 (<5%) received antibiotics >60 min prior to skin incision. The antibiotic timing groups differed in parity (p=0.012) and alcohol use (p<0.001). There was no significant difference in the odds of the primary post-operative composite infection outcome (or any of its individual components) among the timing groups (Table 1). Tests of interaction showed no significant differences in post-infectious morbidity among the randomized groups of antibiotic timing (p>0.05; Table 2). Adjunctive azithromycin administration decreases post-operative infectious morbidity at non-elective cesarean deliveries even when administered more than 60 minutes prior to skin incision or in the postpartum period.View Large Image Figure ViewerDownload Hi-res image Download (PPT)