Out-of-hospital cardiac arrest was studied in suburban King County, Washington in an attempt to determine the impact of paramedic services on community cardiac mortality. A portion of the study area received paramedic services and the remainder received basic emergency medical technician (EMT) services. A surveillance system identified all prehospital cardiac arrest incidents. The etiology and outcome were determined. Deaths due to primary heart disease (ICDA codes 410-414) were compared to community cardiac mortality figures for the same period of time and in the paramedic and EMT areas. Between April 1, 1976 and August 31, 1977, 1,449 deaths due to primary heart disease occurred (annual rate of 19.2/10,000 in the EMT area and 13.4/10,000 in the paramedic area). For the same period, 487 patients with out-of-hospital cardiac arrest received emergency resuscitation. The annual incidence of out-of-hospital cardiac arrest was similar in the EMT and paramedic areas (5.6 and 6.0/10,000 respectively). Proportionately more lives of persons with cardiac arrest were saved in the paramedic area than in the EMT area. During this 17 month period, the reduction in community cardiac mortality was 8.4% in the paramedic area and 1.3% in the EMT. These findings suggest that paramedic services have a small but measurable effect on community cardiac mortality.
