Role of oxytocin in prevention of postpartum hemorrhage in unplanned out-of-hospital deliveries treated by emergency medical services.

ABSTRACT

INTRODUCTION: Intramuscular or intravenous oxytocin is used in out-of-hospital emergency care in Finland to prevent postpartum hemorrhage after unplanned out-of-hospital deliveries. However, the use of oxytocin by emergency medical services is based on in-hospital studies. The aim of this study was to determine whether the use of oxytocin is associated with diminished postpartum hemorrhage after unplanned out-of-hospital deliveries. MATERIAL AND METHODS: We studied patient records covering all unplanned out-of-hospital deliveries in the Helsinki University Hospital area between 1 January 2013 and 31 December 2017 inclusive. Oxytocin was available in ambulances responsible for half of the population of the study area and was not available in ambulances responsible for the other half. The study area corresponded to 25% of all deliveries in Finland. The primary outcome was the estimated total bleeding (mL). Secondary outcomes were (1) the first blood hemoglobin value measured in hospital (g/L), (2) whether blood hemoglobin was measured during the first 24 hours after delivery, (3) the need for red blood cell concentrate, (4) the need for uterotonic or prothrombotic medication in-hospital during the first 24 hours, (5) the need for any postpartum operation during the first 24 hours and (6) composite outcome combining the secondary outcomes 2-5. RESULTS: Of all ambulance responses in the study area, .04% concerned out-of-hospital deliveries. There were 216 analyzed out-of-hospital deliveries. Altogether, 111 of these occurred in the area with oxytocin available in ambulances and 105 in the area without. Oxytocin was administered in 57 of the 111 deliveries (51%) where it was available. No differences in the primary outcome (P = .548 for oxytocin available vs not available and P = .381 for oxytocin used vs not used) or secondary outcomes were detected between those deliveries where oxytocin was available vs not available or between those where it was used vs not used. CONCLUSIONS: Out-of-hospital oxytocin was not associated with diminished postpartum hemorrhage in this study setting. Oxytocin does not seem to be an essential drug for all ambulance units. The in-hospital use of oxytocin was not evaluated and thus is not disputed by this study.