Correlation in Hospital Survival Following Out-of-Hospital Cardiac Arrest With Variation in Post-Arrest Inpatient Intervention Rates in Michigan
Introduction: Wide variations in rates of survival to hospital discharge exist for survivors of out-of-hospital cardiac arrest (OHCA). The potential influence of variation in post-OHCA hospital care has not been adequately explored. We hypothesized that variation of in hospital survival rates may be influenced by variation of in-hospital care in Michigan.
Methods: We performed a secondary analysis of a statewide cardiac arrest database constructed from two probabilistically-linked cardiac arrest registries [Cardiac Arrest Registry to Enhance Survival (CARES) and Michigan Inpatient Database (MIDB)] from 2014 - 2017. A novel composite rank score was created to characterize post-arrest in-hospital care, incorporating four specific interventions: left heart catheterization within 24 hours (LHC), emergent mechanical circulatory support (EMCS), targeted temperature management (TTM), and do-not-resuscitate order placed within 72 hours of arrival (DNR). The highest score (1 of 38) was given to the hospital with highest procedure rate (LHC, TTM, LHC) and the lowest rate of early DNR. Spearman’s correlation coefficients assessed the relationship between the equal weight composite rank score and rate of hospital survivors.
Results: We included 3,644 patients admitted to 38 hospitals who treated >30 OHCA patients during the study period. Patient mean age was 62.4 years, and 59.3% were male. Survival, rank scores and correlation coefficients are listed below: We observed four-fold variation in survival for all patients and witnessed arrest, with a non-significant correlation with care provision. However, we identified a sixteen-fold variation in survival among unwitnessed arrests, which was significantly correlated with a higher rank of care provided.
Conclusions: In Michigan, the greatest variation in survival was identified among unwitnessed arrests. This variation was robustly associated with a composite rank of in-hospital post-arrest interventions.
Swor RA, Paxton J, Berger D, Miller JB, Brett C, Chen NW. Correlation in hospital survival following out-of-hospital cardiac arrest with variation in post-arrest inpatient intervention rates in Michigan. Circulation, 2021 Nov 16;144(Suppl2):A13607.