Background: Supplemental oxygen may reduce postoperative nausea and vomiting after general anesthesia. We designed this study to evaluate the efficacy of supplemental oxygen administration for reducing nausea and vomiting in women having neuraxial anesthesia for cesarean delivery.
Methods: We conducted a prospective, randomized, double-blind study of women having standardized neuraxial anesthesia and postoperative analgesia for cesarean delivery. After umbilical cord clamp, women were randomized to receive either 70% or 21% oxygen for surgery. Nausea and vomiting were recorded at three time intervals: induction until delivery, delivery until the end of surgery, and at 24 postoperative hours. chi2 and Student's t-tests were used to determine significant differences.
Results: The study groups were similar with respect to demographic and procedural variables. There was no significant difference between groups in the overall incidences of nausea and vomiting. The incidence of severe nausea (rated by mothers) in the oxygen group predelivery, postdelivery, and postoperatively was 3%, 7%, and 9%, respectively, and in the medical air group was 3%, 9%, and 7%, respectively. Severe vomiting (>2 episodes) in both the oxygen and medical air groups were 0%, 2%, and 4% at the corresponding time intervals. These differences were not statistically significant.
Conclusion: Administration of supplemental oxygen during cesarean delivery with neuraxial anesthesia does not decrease the incidence or severity of intraoperative or postoperative nausea or vomiting.