SURVIVAL IN THE ELDERLY AFTER OUT-OF-HOSPITAL CARDIAC-ARREST

Objectives: To evaluate the survival prognosis for the elderly (greater-than-or-equal-to 70 yrs of age) after out-of-hospital cardiac arrest in a large urban center, and to identify any specific differences in survival factors relative to those adults <70 yrs of age. Design: The study was a prospective, inception cohort study. Setting: An urban population of approximately 2,000,000, served by one centralized municipal emergency medical services system. Patients: All 986 adult victims (367 elderly and 619 younger patients) of primary cardiac arrest attended by the emergency medical services system over a 12-month period. Interventions: Not applicable. Measurements and Main Results: All victims of out-of-hospital cardiac arrest occurring within a single, large, urban municipality were studied over a 12-month period. Each event was analyzed for age, sex, witnesses, bystander cardiopulmonary resuscitation presenting electrocardiographic rhythm, paramedic response time, scene time, return of spontaneous circulation (pulses), and electrocardiographic rhythm on hospital arrival. Outcomes evaluated included inhospital admission (resuscitation) and successful discharge from the hospital (survival). Patients were followed until death or discharge from the hospital. Of 367 elderly cardiac arrest victims, 81 (22%) Patients were successfully resuscitated and 24 (7%) patients survived. However, of 119 (32% of all elderly patients) patients who presented with ventricular fibrillation/tachycardia, 48 (40%) patients were resuscitated and 17 (14%) patients survived. These 17 patients with ventricular fibrillation/tachycardia accounted for 71% of all elderly survivors. During the same study period, there were 619 adult primary cardiac arrest victims <70 yrs of age, 160 (26%) of whom were resuscitated and 73 (12%) of whom survived. Among the younger patients, 296 (48%) patients presented with ventricular fibrillation/tachycardia, of whom 110 (37%) were resuscitated and of whom 60 patients (20%) survived. Within the context of this study, survival rates for younger and older ventricular fibrillation/tachycardia patients were not significantly different. Also, among survivors, there were no other major differences in terms of established survival determinants. Conclusions: Survival chances for the elderly after out-of-hospital cardiac arrest are not bleak, and are reasonable if ventricular fibrillation/tachycardia is the presenting rhythm. Survival determinants are similar for younger and older adults.