Effect of rescue breathing by lay rescuers for out-of-hospital cardiac arrest caused by respiratory disease: a nationwide, population-based, propensity score-matched study.

The importance of respiratory care in cardiopulmonary resuscitation may vary depending on the cause of cardiac arrest. No previous study has investigated the effects of rescue breathing performed by a lay rescuer on the outcomes of patients with out-of-hospital cardiac arrest (OHCA) caused by intrinsic respiratory diseases. The aim of this study was to investigate whether rescue breathing performed by a lay rescuer is associated with outcomes after respiratory disease-related OHCA. In a nationwide, population-based, propensity score-matched study in Japan, among adult patients with OHCA caused by respiratory disease who received bystander cardiopulmonary resuscitation from January 1, 2005 to December 31, 2010, we compared patients with rescue breathing to those without rescue breathing. The primary outcome was neurologically favorable survival 1 month after OHCA. Of the eligible 14,781 patients, 4970 received rescue breathing from a lay rescuer and 9811 did not receive rescue breathing. In a propensity score-matched cohort (4897 vs. 4897 patients), the neurologically favorable survival rate was similar between patients with and without rescue breathing from a lay rescuer [0.9 vs. 0.7 %; OR 1.23 (95 % CI 0.79-1.93)]. Additionally, in subgroup analyses, rescue breathing was not associated with neurological outcome regardless of the type of rescuer [family member: adjusted OR 0.83 (95 % CI 0.39-1.70); or non-family member: adjusted OR 1.91 (95 % CI 0.79-5.35)]. Even among patients with OHCA caused by respiratory disease, rescue breathing performed by a lay rescuer was not associated with neurological outcomes, regardless of the type of lay rescuer.