Background: Regurgitation is a complication common during cardiopulmonary resuscitation (CPR). This manikin study evaluated the effect of regurgitation during endotracheal intubation on CPR quality.

Methods: An airway-CPR manikin was modified to regurgitate simulated gastric contents into the oropharynx during chest compression during CPR. In total, 54 emergency medical technician-paramedics were assigned to either an oropharyngeal regurgitation or clean airway scenario and then switched to the other scenario after finishing the first. The primary outcomes were CPR quality metrics, including chest compression fraction (CCF), chest compression depth, chest compression rate, and longest interruption time. The secondary outcomes were intubation success rate and intubation time.

Results: During the first CPR-intubation sequence, the oropharyngeal regurgitation scenario was associated with a significantly lower CCF (79.6% vs. 85.1%, P < 0.001), compression depth (5.2 vs. 5.4 cm, P < 0.001), and first-pass success rate (35.2% vs. 79.6%, P < 0.001) and greater longest interruption duration (4.0 vs. 3.0 s, P < 0.001) than the clean airway scenario. During the second and third sequences, no significant difference was observed in the CPR quality metrics between the two scenarios. In the oropharyngeal regurgitation scenario, successful intubation was independently and significantly associated with compression depth (hazard ratio = 0.47, 95% confidence interval, 0.24-0.91), whereas none of the CPR quality metrics were related to successful intubation in the clean airway scenario.

Conclusion: Regurgitation during endotracheal intubation significantly reduces CPR quality.

Trial registration: ClinicalTrials.gov, NCT05278923 , March 14, 2022.