Background: Although survival for out-of-hospital cardiac arrest (OHCA) is lower at emergency medical service (EMS) agencies serving Black/Hispanic communities, it is unknown whether this is due to practice differences.
Methods: Within the Cardiac Arrest Registry to Enhance Survival (CARES) registry in the United States, we conducted a survey from 2022 to 2023 of resuscitation practices at EMS agencies with ≥10 OHCAs annually between 2015 and 2019. We examined differences in dispatch, first responder, and EMS practices between agencies with majority Black/Hispanic catchment areas (>50% residents Black or Hispanic) and majority White catchment areas using χ2 tests. We estimated each agency's risk-standardized rate of survival to hospital admission for OHCA using multivariable hierarchical logistic regression and evaluated whether survival differences between the 2 agency groups were attenuated after adjusting for resuscitation practice differences.
Results: Among 470 EMS agencies (181 707 OHCAs), 47 (10.0%) served a majority Black/Hispanic catchment area. At EMS agencies with Black/Hispanic catchment areas, dispatchers and police first responders were less likely to always recognize a cardiac arrest (29.8% versus 43.0%); police first responders were less likely to respond to OHCA (46.8% versus 68.9%), initiate CPR (59.6% versus 83.2%), or apply an automated external defibrillator (29.8% versus 60.0%); and EMS staff were less likely to assess CPR competency annually (46.5% versus 65.0%) and use waveform capnography (91.5% versus 99.5%), as compared with agencies with White catchment areas. EMS agencies serving majority Black/Hispanic catchment areas had 2% (95% CI, 0.9-3.1%; P<0.001) lower risk-standardized rates of survival, as compared with agencies serving majority White catchment areas, and survival differences were partly attenuated after adjusting for practice differences between EMS groups.
Conclusions: In the United States, we identified differences in dispatcher, first responder, and EMS practices for OHCA between agencies with majority Black/Hispanic and White catchment areas. These practice differences may partly account for disparities in OHCA survival between the 2 EMS agency groups.
Keywords: capnography; defibrillators; hospitals; logistic models; registries.