OBJECTIVES

Labor pain is the most intense pain a woman may experience. This systematic review assessed if a non-pharmacological and inhalational analgesic comprising of 50% medical nitrous oxide and 50 % oxygen is effective in managing delivery pain management in comparison to epidural analgesia.

METHODS

Literature search was done in multiple databases like Pubmed, EMBASE, Cochrane library and Google Scholar. The target population comprised of pregnant women ≥38 weeks gestational age comparing 50% medical nitrous oxide and 50% oxygen with epidural analgesia which is the most commonly used analgesic for delivery pain management. Randomized clinical trials and observational studies were included in the review and they were searched independently by two analysts. The primary outcomes analysed were pain relief, frequency of cesarean section, duration of labor pain.

RESULTS

The literature review found 32 articles, out of which the review included 5 articles based on the inclusion and exclusion criteria. Out of the 5 studies, only one study was found to be of good quality as it was a randomized controlled trial. All the studies are very heterogeneous in many aspects like study design, age, gestation week, pregnancy status, sample size and outcomes in different units etc. and so meta-analysis was not conducted. Results showed that with respect to pain relief, the 50% medical nitrous oxide and 50% oxygen does not provide complete reduction in pain and pain duration when compared to epidural analgesia.

CONCLUSIONS

There is no evidence to suggest that clinicians should consider 50% medical nitrous oxide and 50% oxygen for pain management during delivery of pregnant women. We recommend a non-inferiority trial to compare 50% medical nitrous oxide and 50% oxygen to epidural analgesia with a view of demonstrating that it is not clinically worse with regards to a specific endpoint like delivery pain management.