Association between prehospital airway management methods and neurologic outcome in out-of-hospital cardiac arrest with respiratory cause: a nationwide retrospective observational study

Cardiac arrests are resulted by various aetiology including respiratory cause. Advanced airway placement is an important prehospital intervention for oxygenation and ventilation in respiratory cardiac arrest. We evaluated the association between of advanced airway method and neurologic outcome in arrest with respiratory cause. Adult witnessed non-traumatic OHCA (out-of-hospital cardiac arrest) treated by emergency medical service (EMS) providers in 2013–2017 were enrolled in a nationwide OHCA database. The association between airway management methods (endotracheal intubation (ETI), supraglottic airway (SGA) and bag valve mask (BVM)) and outcome were evaluated according to the presumed cause of cardiac arrest (cardiac, respiratory or others). The primary outcome was good neurological recovery at discharge. Multivariable logistic regression models with interaction analysis was conducted. Of 40,443 eligible OHCA patients, the cause of arrest of 90.0%, 7.5%, and 2.4% of patients were categorized as cardiac, respiratory and others, respectively. There were no statistically significant differences in the effect of the advanced airway type on good neurologic recovery in the total population (adjusted odds ratio (aOR) 0.96 (0.81–1.14) for ETI; 1.01 (95% confidence intervals (CI) 0.93–1.11) for BVM). However, ETI was associated with better neurologic recovery than SGA or BVM in OHCA in cardiac arrest with suspected respiratory cause (aOR 3.12 (95% CI 1.24–7.80) for ETI; 0.99 (95% CI 0.51–1.91) for BVM). Prehospital ETI was associated with good neurologic outcome when the cause of arrest was respiratory. ETI may be considered initially when a respiratory cause is suspected on the scene.