Retrospective evaluation of the impact of implementation of a new oxytocin administration protocol on uterotonic use and maternal hypotension
Abstract Number: 97
Abstract Type: Original Research
BACKGROUND: The, active management of the 3rd stage of labor, which includes the initiation of oxytocin immediately after fetal delivery, has been shown to reduce bleeding complications without increasing adverse outcomes (1). High infusion rates of oxytocin have been associated with adverse hemodynamic changes, particularly hypotension (2). We recently initiated routine active management of the 3rd stage (oxytocin 18 IU/h initiated at delivery). The purpose of this study was to evaluate the effect the new oxytocin infusion protocol on hypotension and the administration of supplemental uterotonics. Prior to the protocol implementation there was no uniform management of the 3rd stage of labor or maximum oxytocin infusion rate.
METHODS: 10% of the parturients receiving neuraxial analgesia during a 4 month period surrounding protocol initiation were randomly selected for retrospective review. Data collection included the amount of oxytocin infused following delivery, administration of supplemental uterotonics (methylergonovine, prostaglandin 15-methyl F2α, or misoprostol), hypotension requiring vasopressor administration, and estimated blood loss (EBL). Data was stratified by the mode of delivery and compared between pre- and post-protocol implementation using the Mann-Whitney U test and a χ2 statistic. A P<0.05 was required to reject the null hypothesis.
RESULTS: 436 patients were included in the analysis. In the vaginal delivery (VD) group the total amount of oxytocin administered increased and the incidence of hypotension decreased; however, there was no difference in the EBL or incidence of supplemental uterotonic use. In the cesarean delivery (CD) group, the total oxytocin dose decreased and there was no change in supplemental uterotonic or vasopressor administration, but EBL increased.
CONCLUSIONS: The active management of the 3rd stage of labor in VD patients may increase the total oxytocin administered without adverse outcomes. The total oxytocin dose after CD decreased, but vasopressor use was unchanged. The possible increase in blood loss with protocol implementation following CD is not likely to be clinically significant. The trend towards greater uterotonic administration following the protocol implementation may reflect early use of uterotonics by the obstetrician during the initial protocol implementation, but merits further long-term follow-up.
1) Cochrane Database of Systematic Reviews 2001; 4:1-65
2) IJOA 2002; 11:156-9