Background: In-hospital management of out-of-hospital cardiac arrest (OHCA) is heavily influenced by the initial rhythm (shockable vs. non-shockable). The prevalence of discordance between initial rhythm determination reported by emergency medical services (EMS) versus hospital teams is not well described. It is unclear whether such documentation discrepancies in OHCA influence inpatient clinical care including subsequent left heart catheterization (LHC). We hypothesized that discordance between EMS and hospital team documentation of OHCA initial rhythm was common and associated with differences in LHC frequency. Methods: This was a retrospective, single-center study. OHCA patients from the Cardiac Arrest Registry to Enhance Survival (CARES) hospital database were linked by demographic and arrest history to OHCA patients identified by inpatient hospital billing codes from 2009 to 2017. Patients who expired within 24 hours of hospital presentation were excluded. Hospital documentation of OHCA initial rhythm and occurrence of LHC were manually reviewed. The relationship between EMS versus hospital team documentation of OHCA initial rhythm and occurrence of LHC were assessed by relative risk ratios with 95% confidence intervals. Results: Out of 164 patients for analysis, 140 (85.4%) had concordant EMS and hospital documentation of OHCA initial rhythm. For OHCA with an EMS-documented shockable rhythm, the relative risk of LHC when hospital-documented concordant shockable vs. discordant non-shockable rhythm was 2.12 (95% RR CI: 0.76-5.93). For OHCA with an EMS-documented non-shockable rhythm, the relative risk of LHC when hospital-documented concordant non-shockable vs discordant shockable rhythm was 0.19 (95% CI: 0.05-0.69). Conclusions: In patients with OHCA, discrepancy between EMS and hospital team documentation of the initial arrest rhythm is prevalent. This discrepancy may influence the incidence of LHC. Further research is needed to understand the clinical impact of discrepancies in rhythm communication between EMS and hospital teams.

The authors have declared no competing interest.

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

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