(319) Impact of the Oxytocin Shortage on Postpartum Bleeding Outcomes

Objective: National oxytocin shortages led our institution to modify our postpartum (PP) oxytocin protocol. Our objective was to compare rates of postpartum hemorrhage (PPH) and the need for additional PPH interventions before and during the oxytocin shortage.

Study Design: We performed a retrospective cohort study of all deliveries >22 weeks at a large academic referral center from 4/2022-1/2023. Prior to oxytocin shortages, we utilized a high-dose PP oxytocin regimen of 80 units/500 mL after vaginal deliveries and two bags of 80 units/500 mL after cesareans. With the shortage, we transitioned on 10/12/22 to 60 units/1000 ml after vaginal deliveries and one bag of 80 units/500 ml after cesareans. The primary outcome was a composite of activation of the institution’s quantitative PPH protocol, any uterotonic use, any blood transfusion, and PPH based on EBL (see Table footnote). Secondary outcomes included individual constituents in the composite and other bleeding outcomes (Table). Outcomes were compared between pre-shortage and during shortage groups and logistic regression was used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CI) using the pre-shortage group as reference.

Results: Of 2988 deliveries in our study period, 2422 deliveries were included- 1747 pre-shortage and 675 during. Individuals before the shortage were more likely to have a BMI >30, be nulliparous, have a prior cesarean, undergo cesarean, have antepartum magnesium use, have preeclampsia, and less likely to have intrapartum oxytocin. There was no significant difference in the primary composite outcome between time periods (pre-shortage 15.0% vs shortage 12.2%; aOR 0.92 [0.70-1.22]) (Table). Secondary outcomes were also similar between groups. Results were unchanged when stratified by delivery mode.

Conclusion: Rates of PPH and postpartum bleeding interventions were unchanged after PP oxytocin dose reduction during the oxytocin shortage at our institution. When using a high-dose postpartum prophylactic oxytocin regimen, slight reductions in oxytocin did not alter bleeding outcomes.