Out-of-hospital cardiac arrests terminated without full resuscitation attempts: Characteristics and regional variability

Background Out-of-hospital cardiac arrest (OHCA) investigations may elect to exclude cases with resuscitation terminated for reasons other than a full resuscitative attempt. We sought to examine characteristics of these cases and regional variability in classification. Methods Using the North American Resuscitation Outcomes Consortium Epistry, we included adult emergency medical services (EMS)-treated cases, examining the rationale (“futility”, do-not resuscitate [DNR] order, “verbal directive“, or “obvious death”) and timing of resuscitation termination, and the timing of ROSC among hospital-discharge survivors. We tested regional variability in EMS patient arrival-to-termination intervals with one-way ANOVA. Results Of 63,554 included cases, 27,232 were declared dead in the prehospital setting: (1) 23,009 (36%) for futility (after a median of 24 minutes [IQR 19–31] of professional resuscitation); (2) 1622 (2.6%) for a DNR order (at 6.3 minutes [IQR 3.0–11]); (3) 1018 (1.6%) for a verbal directive (at 12 minutes [IQR 7.0–17]); and, (4) 1583 (2.5%) for obvious death (at 5.4 minutes [IQR 3.0–9.0]). The EMS patient arrival-to-ROSC interval among hospital-discharge survivors was 7.7 (3.8–13) minutes. Among regions, 0.20–12% and 0.20–5.3% were terminated to due to obvious death or verbal directives, respectively. There were significant regional differences in the EMS patient arrival-to-termination interval for futility (p < 0.010) and obvious death (p < 0.010). Conclusion There is significant variation in the rationale and interval until termination of resuscitation between regions. Cases terminated due to obvious death or DNR orders/verbal directives are often treated with similar durations of resuscitation as survivors. These data highlight a considerable risk of bias in between-region comparisons or observational analyses.