Effect of pre-hospital advanced airway management for out-of-hospital cardiac arrest caused by respiratory disease: a propensity score matched study

Optimal pre-hospital care for out-of-hospital cardiac arrest (OHCA) caused by respiratory disease may differ from that for OHCA associated with other aetiologies, especially with respect to respiratory management. We aimed to investigate whether pre-hospital advanced airway management (AAM) was associated with favourable outcomes after OHCA caused by intrinsic respiratory disease. This nationwide, population-based, propensity score matched study of adult patients in Japan with OHCA due to respiratory disease from 1 January 2005 to 31 December 2012 compared patients with and without pre-hospital AAM. The primary outcome was neurologically favourable survival at one month after the OHCA. Of 49,534 eligible patients, 20,458 received pre-hospital AAM and 29,076 did not. In a propensity score matched cohort (18,483 versus 18,483 patients), the odds of neurologically favourable survival were significantly lower for patients receiving pre-hospital AAM (0.6% versus 1.5%; odds ratio [OR] 0.42 [95% confidence interval {CI} 0.34 to 0.52]). The results from multivariable logistic regression analysis also showed that pre-hospital AAM was significantly associated with a decreased chance of neurologically favourable survival (adjusted OR 0.43 [95% CI 0.35 to 0.52]). Similar findings were observed for one-month survival and pre-hospital return of spontaneous circulation. In subgroup analyses, pre-hospital AAM was associated with poor neurological outcomes, regardless of the type of airway device used (laryngeal mask airway, adjusted OR 0.35 [95% CI 0.19 to 0.57]; oesophageal obturator airway, adjusted OR 0.44 [95% CI 0.35 to 0.55]; and endotracheal tube, adjusted OR 0.47 [95% CI 0.30 to 0.69]). In conclusion, pre-hospital AAM was associated with poor neurological outcome among patients with OHCA caused by intrinsic respiratory disease.