Nitrous Oxide in Labor: Predictors of Use and Conversion to Epidural Anesthesia [20P]. (May 2018)

• Record Type: Journal Article
• Authors: Brumley, Jessica; Obican, Sarah; Kendle, Anthony; Louis, Judette
• Is Part Of: Obstetrics and gynecology. Volume 131(2018)Supplement 1
• Publication Date: 2018-05
• Subjects: Obstetrics -- Periodicals; Gynecology -- Periodicals; 618
• DOI: 10.1097/01.AOG.0000533194.20874.0d
• Languages: English
• ISSNs: 0029-7844

Abstract

Abstract : INTRODUCTION: We evaluated factors associated with conversion from nitrous oxide (NO2 ) to epidural anesthesia in laboring women. METHODS: We conducted a retrospective cohort study including women who delivered at an academic tertiary center during 1/1/2015-6/30/2017. Women with planned Cesarean delivery or with multiple gestations were excluded. At this center, self-administered NO2, intravenous opioids and epidural anesthesia are routinely offered. Electronic databases and medical charts were reviewed. Characteristics of women were compared using χ 2, students T-test and Mann Whitney U test and logistic regression. P < 0.05 was considered significant. RESULTS: Among 13, 615 women admitted for trial of labor, 16.9% (n=2, 265) used NO2 for labor analgesia. NO2 use increased annually 16.2%, 16.8% and 18%, p=.02 from 2015-2017. Women who used NO2 were more likely to be Caucasian, nulliparous, commercially insured, and have induced labor. The NO2 group was more likely to have maternal comorbid conditions or fetal indication for delivery, and these factors were predictive of conversion to epidural anesthesia. Women using NO2 were less likely to have a subsequent epidural placement, undergo a Cesarean delivery or have a NICU admission. Women were more likely to convert from NO2 to epidural anesthesia if they were Black, of Middle Eastern descent, Hispanic, obese, or nulliparous. Labor induction and augmentation were not predictive of conversion to neuraxial anesthesia. CONCLUSION: Use of NO2 in this ethnically diverse cohort was not associated with morbidity. These predictors of residual need for epidural anesthesia can assist in counseling patients prior to delivery.