Abstract Sat1108: Does Out-of-hospital Cardiac Arrest Survival Differ by EMS Agency Type in the US? Insights from the CARES Registry

Background: There are limited data on whether out-of-hospital cardiac arrest (OHCA) survival differs by EMS agency type in the U.S. Methods: Within the Cardiac Arrest Registry to Enhance Survival (CARES) registry, we surveyed participating EMS agencies with > 20 OHCA annually during 2015-2019. Agencies were categorized as fire department, private (includes profit and nonprofit entities), government service, and other. Using multivariable hierarchical logistic regression, we computed the risk-standardized survival rate (RSSR) to hospital admission and to hospital discharge for each EMS agency’s OHCA patients and examined for differences in RSSRs across agency types using the Mantel-Haenszel test for trend. Results: Of 577 eligible EMS agencies, 470 (81.5%) completed the survey. Overall, 40.0% of agencies were categorized as fire-based, 35.0% as private, 17.3% as government service, and 7.7% as other. The mean agency-level RSSR to hospital admission for OHCA was 27.8% + 3.6% and was highest in fire-based EMS agencies (28.9%) and lowest in private and hospital-based agencies (each at 26.8%; p<0.001 for comparison across all groups). The mean agency-level RSSR to hospital discharge was 10.1% + 1.8% and was highest in fire-based EMS agencies (10.3%) and lowest in private and hospital-based agencies (9.7%; p<0.003 across all groups). Fire-based agencies were more likely to have lower annual cardiac arrest dispatch run burden per paramedic, have more hours of OHCA training during orientation, provide telephone instructions to administer CPR to bystanders, use a mechanical CPR and impedance threshold device, and have shorter times of arrival at the scene and transport to the hospital. (Table) Conclusions: In the U.S., OHCA survival differs by EMS agency type. Agencies that are fire-based have the highest survival with key practice differences that may distinguish its survival from other agency types.