Trends and variation in use of end-tidal carbon dioxide during in-hospital cardiac arrest: an observational cohort study.

Background: The American Heart Association recommends using end-tidal carbon dioxide during cardiac arrest for advanced airway confirmation and for monitoring and optimizing cardiopulmonary resuscitation; practice patterns of its use during in-hospital cardiac arrest are not well described. Methods: We used the prospectively collected get with the guidelines-resuscitation registry to characterize trends and hospital-level variation in end-tidal carbon dioxide use for airway confirmation in arrests with a newly placed airway, and to monitor cardiopulmonary resuscitation in arrests with a new or prior airway. Proportions were displayed by month from 2000 to 2023. Hospital use rates were displayed visually and calculated for contemporary practice (2019-2023). Proportions were reported using means or medians depending on the distribution. Results: Among 257,057 in-hospital cardiac arrests with a new airway, 92.6% were confirmed with end-tidal carbon dioxide in 2019-2023. Among the 554,693 in-hospital cardiac arrests with either a new airway or an airway already in place, 35.3% had end-tidal carbon dioxide applied for monitoring cardiopulmonary resuscitation in 2019-2023. There was little variation in hospital proportions for airway confirmation, with a median of 94.0%; however, a high degree of variation was observed across hospitals for monitoring cardiopulmonary resuscitation. Conclusion: End-tidal carbon dioxide application is widespread for confirming airway placement during in-hospital cardiac arrest, but gaps remain in adherence to guideline recommendations for monitoring cardiopulmonary resuscitation with end-tidal carbon dioxide.