Efficacy of an Alternative Oxytocin Dosing Regimen for Postpartum Hemorrhage Prevention at Cesarean Delivery [13P

Abstract

INTRODUCTION: In 2013, the University of New Mexico Hospital transitioned from a 20IU oxytocin infusion to a “rule of threes” algorithm (3 IU of oxytocin titrated to uterine tone) for prevention of postpartum hemorrhage (PPH) at time of cesarean delivery. This study seeks to identify whether PPH rates have been affected by this change in oxytocin dosing. METHODS: This is a retrospective cohort study comparing PPH rates before and after an institutional shift in oxytocin administration at the time of cesarean delivery. IRB exemption was obtained for this study. Medical records were reviewed for scheduled and unscheduled cesarean section patients before and after the protocol change. 225 patients in each group were randomly selected for the analysis. Our primary outcome was the rate of PPH, determined by estimated blood loss reported by the surgeon. Secondary outcomes included administration of additional uterotonic agents, transfusion, hysterectomy, vasopressor administration, and mortality. RESULTS: There were no significant differences in age, gravidity, parity, prior number of cesarean sections, gestational age, BMI, fetal weight, or induction of labor. Women who received the 20IU oxytocin infusion had a significantly lower rate of PPH (22.2%) compared to “rule of threes” dosing (32.4%, Fishers test P=.0198). CONCLUSION: Our data show an increased rate of PPH with a rule of threes oxytocin dosing at the time of cesarean section compared with infusion dosing of oxytocin. These data indicate that rule of threes dosing may not be applicable to a wider patient population.