Oxytocin infusion's ED90 for preventing postpartum hemorrhage in elective C-sections to be determined

Postpartum hemorrhage (PPH) remains a leading cause of maternal morbidity and mortality globally, with uterine atony accounting for 70-80% of cases. Rapid achievement of uterine tone is crucial due to very high uterine blood flow at term. While oxytocin is the most widely used uterotonic for PPH prevention, high-quality data comparing bolus versus infusion administration, and specifically identifying the minimum effective dose, are limited. Optimizing oxytocin protocols could significantly improve maternal outcomes by ensuring effective, yet safe, dosing.

This Phase 4 randomized clinical trial (NCT03584854) enrolled 100 low-risk parturients undergoing elective C-sections. The study utilized an 'up-down' design to determine the minimum effective dose (ED90) of oxytocin infusions for preventing uterine atony. The primary outcome was the obstetrician-blinded assessment of effective uterine contraction as either satisfactory or unsatisfactory. Secondary outcomes included the need for additional uterotonics, calculated intra-operative blood loss, and the presence of oxytocin-related adverse effects.