Impact of Nitrous Oxide Use on Parturient Recall of Neuraxial Analgesia Risks

( J Clin Anesth . 2024;98:111579. doi: 10.1016/j.jclinane.2024.111579) Labor analgesia can take several forms, among which are nitrous oxide and intravenous opioids. Nitrous oxide is often used in European countries and has been gaining popularity among patients in the United States as well. It has been shown to be less effective than intravenous opioids or neuraxial blocks, and many patients (up to 40%) transfer to neuraxial analgesia during labor, but patient satisfaction scores for nitrous oxide remain high. Transitioning from one method of pain relief to another requires informed consent, which may be problematic due to the effects of nitrous oxide making recall and comprehension poor depending on the individual and the dose. This study was designed to assess if the use of 50% nitrous oxide affected the abilities of patients to learn, retain, and recall information about the risks and benefits of neuraxial labor analgesia, with the hypothesis that information recall would differ between those who received nitrous oxide and those who did not.