Community Disparities in Out-of-Hospital Cardiac Arrest Prehospital Antiarrhythmic Practices

Antiarrhythmic administration is an important treatment for out-of-hospital cardiac arrest (OHCA) with a shockable rhythm, but a minimal amount is known about disparities in such antiarrhythmic practices. We sought to investigate the association between community race/ethnicity and prehospital antiarrhythmic administration for OHCA.

We conducted a retrospective study of a national prehospital database, National Emergency Medical Services Information System (NEMSIS), linked to Census data. We included OHCAs with a shockable rhythm from 2018 to 2021. We stratified patients based on majority (>50%) ZIP code race/ethnicity (non-Hispanic White (White), non-Hispanic Black (Black), and Hispanic/Latino). We then created two cohorts: (1) patients with a shockable rhythm at any point to study differences in antiarrhythmic administration rates, and (2) patients with an initial shockable rhythm to analyze differences in time to antiarrhythmic administration. For patients with a shockable rhythm at any point, we used logistic regressions to evaluate the association of community race to antiarrhythmic administration. For patients with an initial shockable rhythm, we compared the time from emergency medical services (EMS) dispatch to the first antiarrhythmic administration.

Of 763,944 cardiac arrests, 311,499 had a shockable rhythm during the OHCA, and 237,838 had an initial shockable rhythm. For patients with a shockable rhythm at any point, majority White (33.0%) received antiarrhythmics at a higher rate than majority Black (28.9%; aOR 0.9, 95%CI 0.8-0.9) and majority Hispanic/Latino (27.8%; aOR 0.8 95%CI 0.7-0.8). For patients with an initial shockable rhythm, the time to antiarrhythmic for White (median 19.6 min, IQR 15.00-26.28 min) was lower than for Black (median 20.5 min, IQR 16.33-26.35 min, p < 0.01) but higher than Hispanic/Latino (median 18.0 min, IQR 14.33-23.42 min, p < 0.01).

While antiarrhythmic administration rate was lower for minority communities and time to antiarrhythmic was higher for Black OHCAs, time to antiarrhythmic administration was lower for Hispanic/Latino OHCAs.