Practice Patterns and Adverse Events of Nitrous Oxide Sedation and Analgesia: A Report from the Pediatric Sedation Research Consortium

J Pediatr. 2016 Feb:169:260-5.e2. doi: 10.1016/j.jpeds.2015.10.019. Epub 2015 Nov 5.


Objectives: To describe practice patterns and adverse events associated with nitrous oxide (N2O) administration as the primary sedative outside the operating room in varied settings by a diverse range of providers, and to identify patient and sedation characteristics associated with adverse events.

Study design: Data prospectively collected by the Pediatric Sedation Research Consortium, which is comprised of 40 children's and general/community hospitals, was retrospectively analyzed for children who received N2O as the primary sedative. Descriptive measures of patient and sedation characteristics and adverse events were reported. A multivariable regression model was used to assess potential associations between patient and sedation characteristics and adverse events.

Results: A total of 1634 N2O administrations were identified. The majority was performed in sedation units, and most by advanced practice nurses or physician assistants. The most common adjunct medication was midazolam. There was a low prevalence of adverse events (6.5%), with vomiting as the most common (2.4%) and only 3 (0.2%) serious adverse events reported. The odds of vomiting increased when concomitant opioids were administered (OR 2.89, 95% CI 1.14, 7.32) and when nil per os (NPO) clear fluids <2 hours (OR 4.16, 95% CI 1.61, 10.76). NPO full meal <6 hours did not change the odds of vomiting (OR 1.42, 95% CI 0.57, 3.57). There were no aspiration events.

Conclusions: There was a very low prevalence of serious adverse events during N2O administration in children outside of the operating room and by nonanesthesiologists. The odds of vomiting increased when concomitant opioids were administered and NPO clear fluids <2 hours.

MeSH terms

  • Adolescent
  • Analgesia / methods
  • Analgesia / statistics & numerical data*
  • Anesthesia, Inhalation / adverse effects*
  • Child
  • Child, Preschool
  • Conscious Sedation / methods
  • Conscious Sedation / statistics & numerical data*
  • Female
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Nitrous Oxide / adverse effects*
  • Practice Patterns, Physicians' / statistics & numerical data*
  • Prospective Studies
  • Regression Analysis
  • Retrospective Studies
  • Young Adult


  • Nitrous Oxide