LAUSR

Objectives To investigate the association of prehospital advanced airway management (AAM) on outcomes of emergency medical service (EMS)-witnessed out-of-hospital cardiac arrest (OHCA) according to the location of arrest. Methods We evaluated a Korean national OHCA database from 2012 to 2016. Adults with EMS-witnessed, non-traumatic OHCA were included. Patients were categorised into four groups according to whether prehospital AAM was conducted (yes/no) and location of arrest (‘at scene’ or ‘in the ambulance’). The primary outcome was discharge with good neurological recovery (cerebral performance category 1 or 2). Multivariable logistic regression analysis was conducted to evaluate the association between AAM and outcome according to the location of arrest. Results Among 6620 cases, 1425 (21.5%) cases of arrest occurred ‘at the scene’, and 5195 (78.5%) cases of arrest occurred ‘in an ambulance’. Prehospital AAM was performed in 272 (19.1%) OHCAs occurring ‘at the scene’ and 645 (12.4%) OHCAs occurring ‘in an ambulance’. Patients with OHCA in the ambulance who had prehospital AAM showed the lowest good neurological recovery rate (6.0%) compared with OHCAs in the ambulance with no AAM (8.9%), OHCA at scene with AAM (10.7%) and OHCA at scene with no AAM (7.7%). For OHCAs occurring in the ambulance, the use of AAM had an adjusted OR of 0.67 (95% CI 0.45 to 0.98) for good neurological recovery. Conclusion Our data show no benefit of AAM in patients with EMS-witnessed OHCA. For patients with OHCA occurring in the ambulance, AAM was associated with worse clinical outcome.