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

Objectives: To evaluate the survival prognosis for the elderly (greate r-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 pop ulation of approximately 2,000,000, served by one centralized municipa l emergency medical services system. Patients: All 986 adult victims ( 367 elderly and 619 younger patients) of primary cardiac arrest attend ed by the emergency medical services system over a 12-month period. In terventions: Not applicable. Measurements and Main Results: All victim s 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 resuscita tion presenting electrocardiographic rhythm, paramedic response time, scene time, return of spontaneous circulation (pulses), and electrocar diographic rhythm on hospital arrival. Outcomes evaluated included inh ospital admission (resuscitation) and successful discharge from the ho spital (survival). Patients were followed until death or discharge fro m the hospital. Of 367 elderly cardiac arrest victims, 81 (22%) Patien ts were successfully resuscitated and 24 (7%) patients survived. Howev er, of 119 (32% of all elderly patients) patients who presented with v entricular fibrillation/tachycardia, 48 (40%) patients were resuscitat ed and 17 (14%) patients survived. These 17 patients with ventricular fibrillation/tachycardia accounted for 71% of all elderly survivors. D uring the same study period, there were 619 adult primary cardiac arre st 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 ventricul ar 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 f or the elderly after out-of-hospital cardiac arrest are not bleak, and are reasonable if ventricular fibrillation/tachycardia is the present ing rhythm. Survival determinants are similar for younger and older ad ults.