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Use of Nitrous Oxide in Labor and Possible Interaction with Systemic Opioids or Sedatives/Hypnotics

  • July 2021

This Practice Advisory was developed by the American College of Obstetricians and Gynecologists' Committee on Clinical Practice Guidelines—Obstetrics in collaboration with Kathleen Brookfield, MD, PhD, MPH; Manisha Gandhi, MD; Anjali J. Kaimal, MD, MAS; and Megan McReynolds.


The use of nitrous oxide (N2O) in labor is addressed in Practice Bulletin No. 209, “Obstetric Analgesia and Anesthesia” 1 . In the Practice Bulletin, it is described that nitrous oxide can be used safely with other forms of analgesia. However, a statement from the American Society of Anesthesiologists noted that in the setting of nitrous oxide analgesia, the addition of systemic opioids or sedatives/hypnotics may lead to deeper levels of sedation and increase the risk of respiratory depression and associated maternal hypoxemic episodes 2 . As a result, if a combination of opioids or sedatives/hypnotics with nitrous oxide is used for labor analgesia, there may be increased risk of adverse events.

Based on this concern for potential maternal adverse consequences, co-administration of systemic opioids or sedatives/hypnotics and inhaled nitrous oxide for labor analgesia is not recommended.


References

  1. Obstetric analgesia and anesthesia. ACOG Practice Bulletin No. 209. American College of Obstetricians and Gynecologists. Obstet Gynecol 2019;133:e208-25. doi: 10.1097/AOG.0000000000003132.
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  2. Rollins MD, Arendt KW, Carvalho B, Vallejo M, Zakowski M. Nitrous oxide. Accessed July 21, 2021. Available at: https://www.asahq.org/about-asa/governance-and-committees/asa-committees/committee-on-obstetric-anesthesia/nitrous-oxide.
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A Practice Advisory is a brief, focused statement issued to communicate a change in ACOG guidance or information on an emergent clinical issue (e.g., clinical study, scientific report, draft regulation). A Practice Advisory constitutes ACOG clinical guidance and is issued only online. Practice Advisories are reviewed periodically for reaffirmation, revision, withdrawal or incorporation into other ACOG guidelines.

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The American College of Obstetricians and Gynecologists (ACOG), is the nation's leading group of physicians providing health care for women. As a private, voluntary, nonprofit membership organization of more than 58,000 members, ACOG strongly advocates for quality health care for women, maintains the highest standards of clinical practice and continuing education of its members, promotes patient education, and increases awareness among its members and the public of the changing issues facing women's health care. www.acog.org