Pre-hospital airway management and neurological status of patients with out-of-hospital cardiac arrest: A retrospective cohort study

Purpose: Little is known about whether pre-hospital advanced airway management (AAM) under the presence of a physician could improve outcome of patients with cardiac arrest, compared with pre-hospital AAM under the absence of a physician.Methods: This retrospective multicentre-cohort study enrolled consecutive patients who were transported to participating hospitals after out-of hospitalcardiac arrest in Japan between 1 June 2014 and 31 December 2019. We included patients who underwent pre-hospital AAM and resuscitation after arrival at hospital, and who were >18 years of age, with medical aetiologies. The primary outcome was favourable neurological survival (Cerebral Performance Category score of 1 or 2) one month after cardiac arrest. The primary outcome was called one-month favourable neurological survival. The first confirmed cardiac rhythm was defined using 3-lead electrocardiogram monitor or an automated external defibrillator and by determining whether the carotid artery was pulsating. Previous research found that the presence of a pre-hospital physician was associated with improved patients' outcomes, after the type of first confirmed cardiac rhythm was considered. Therefore, the first confirmed cardiac rhythm in current study was subdivided into non-shockable or shockable groups. A multivariable logistic regression analysis was performed on propensity score-matched patients.Results: We analysed 16,703 patients. Among the 2,346 patients in the non-shockable group, 1.2% (N = 29) achieved the primary outcome. The adjusted odds ratio of pre-hospital AAM with or without a physician for the primary outcome in the results of the non-shockable group was 4.64 (95% confidence interval: 1.81-14.4). Among the 826 patients in the shockable group, 16.9% (N = 140) achieved the primary outcome and the adjusted odds ratio of pre-hospital AAM with or without a physician for the primary outcome in the results of the shockable group was 1.05 (95% confidence interval: 0.67-1.63).Conclusions: This retrospective multicentre-cohort study found that pre-hospital AAM under the presence of a physician was significantly associated with increased neurological outcome in specific patients with cardiac arrest, compared with pre-hospital AAM under the absence of a physician.