Intrapartum Nitrous Oxide: Satisfaction, Side Effects, and Predictors of Conversion

In 2015, the Intrapartum Nitrous Oxide Workgroup (I-NOW group) designed a multi-institutional database, Intrapartum Nitrous Oxide Database (I-NOW database), to collect data on births during which N2O was used. The goal of compiling data on N2O use from a variety of U.S. institutions was to evaluate unaddressed aspects of intrapartum N2O use with a focus on safety and best-use practices. This dataset holds data from one institution in the workgroup for 463 intrapartum adult (≥ 18 years old) patients who used nitrous oxide. The data points include demographics, medical history, obstetric history, side effects and satisfaction scores for nitrous oxide, conversion to other methods, and reasons for conversion. Labor induction, medical augmentation, parity, trial of labor after cesarean delivery (TOLAC), and post-nitrous cervical dilation all had significant effects on the rate of conversion to neuraxial analgesia. Side effects related to inhaled N2O use during labor were rare and were not a significant reason for conversion to neuraxial analgesia. Newborn Apgar scores averaged 8 and 9 at 1 and 5 minutes respectively.