EMS-witnessed cardiac arrest: Descriptive epidemiology, predictors of survival, and survival comparison with bystander-witnessed cardiac arrest.

Abstract

Statement of the problem. Cardiac arrest is the leading cause of death in Canada, yet it remains a problem with extremely poor prognosis. The prehospital response to cardiac arrest is critical since the majority of these events occur in the community, prior to the patient being transported to hospital. Cardiac arrests that occur after the arrival of trained emergency medical services (EMS) personnel (either ambulance or firefighters) may be a particularly homogeneous subgroup in which to assess not only mechanisms of cardiac arrest, but also the effectiveness of prehospital systems, and thereby contribute to our current understanding of the cardiac arrest condition. Objectives. The objectives of this study are threefold: (1) to elucidate the epidemiology of EMS-witnessed cardiac arrest in Ontario in terms of demographics, EMS-system and clinical characteristics, and rates of incidence and survival; (2) to determine predictors of survival to hospital discharge in this group; and (3) to compare outcomes among EMS-witnessed and bystander-witnessed cardiac arrest. (Abstract shortened by UMI.)