Early endotracheal intubation improves neurological outcome following witnessed out-of-hospital cardiac arrest in Japan: a population-based observational study

Aim: It is unclear whether endotracheal intubation in the prehospital setting improves outcomes following out-of-hospital cardiac arrest. The purpose of this study was to evaluate the association between endotracheal intubation time (time from patient contact to endotracheal intubation) and favorable neurological outcomes on out-of-hospital cardiac arrest. Methods: We extracted patients who underwent endotracheal intubation on the scene from a nationwide out-of-hospital cardiac arrest database registered between 2014 and 2017 in Japan. We included 14,969 witnessed and intubated adult out-of-hospital cardiac arrest cases. Patients were divided into Shockable (n = 1,102) and Non-shockable (n = 13,867) cohorts. We first drew the logistic curve due to predicting the association between endotracheal intubation time and favorable neurological outcome defined as Cerebral Performance Category (CPC) 1 or 2. Secondary, multivariable logistic regressions were used to estimate the association between the endotracheal intubation time (1-min unit increase), CPC 1 or 2. Results: The logistic curve for CPC 1 or 2 showed similar shapes and indicated a decreasing outcome over time. From the results of multivariable logistic regression, in the Shockable cohort, endotracheal intubation time delay was correlated with decreasing favorable outcomes: CPC 1 or 2 (adjusted odds ratio, 0.89; 95% confidence interval, 0.82-0.87). Results were the same for the Non-shockable cohort: CPC 1 or 2 (adjusted odds ratio, 0.94; 95% confidence interval, 0.89-0.99). Conclusion: Early endotracheal intubation was correlated with favorable neurological outcome. Training for intubation skills and improving protocols are needed for carrying out early endotracheal intubation.