Several key features appear to influence out-of-hospital cardiac arrest survival to hospital admission, according to a study. The strongest independent factors associated with successful resuscitation were shockable primary rhythm, witnessed arrest, and out-of-hospital cardiac arrest in a public area. During the 4-year study period, the rate of patients with a high comorbidity burden increased from 18% to 31%. However, the rate of successful resuscitation increased from 37% to 43%, suggesting a positive effect of systematic care that has matured.

Source: Annals of Emergency Medicine, May 2015.