Evaluation of an emergency medical system. The prognosis in patients with an out-of-hospital cardiac arrest.

In a retrospective chart review, we evaluated the efficiency of the emergency medical system of the Leiden area in patients with an out-of-hospital cardiac arrest. A total of 309 adult patients were included. Two hundred patients (64.7%) died in the emergency department and 67 (21.7%) died during subsequent hospital stay. Finally, 42 patients (13.6%) survived after hospital discharge. Favourable prognostic factors were the presence of witnesses at the time of arrest, a short call-response interval, an initial cardiac rhythm of ventricular fibrillation or tachycardia, and adequate advanced cardiac life support provided by the emergency medical system. We detected several shortcomings in the system such as an unacceptably prolonged call-response interval for some patients at the periphery of the Leiden area and a delay in the first defibrillation attempt. Improvement of this "pre-hospital chain of survival" is likely to result in a better outcome for these patients.