Neurological Favorable Outcomes Associated with EMS Compliance and On-Scene Resuscitation Time Protocol

Abstract

Purpose: Korean national emergency care protocol for EMS providers recommends a minimum of 5minutes of on-scene resuscitation before transport to hospital in cases of Out-of-Hospital Cardiac Arrest (OHCA). We compared survival outcome of OHCA patients according to scene time interval (STI)-protocol compliance of EMS. Methods: EMS treated adult OHCAs with presumed cardiac etiology during a two-year period were analyzed. Non-compliance was defined as hospital transport with STI less than 6minutes without return of spontaneous circulation (ROSC) on scene. Propensity score for compliance with protocol was calculated and based on the calculated propensity score, 1:1 matching was performed between compliance and non-compliance group. Univariate analysis as well as multivariable logistic model was used to evaluate the effect of compliance to survival outcome. Results: Among a total of 28,100 OHCAs, EMS transported 7,026 (25.0%) cardiac arrests without ROSC on the scene with an STI less than 6minutes. A total of 6,854 cases in each group were matched using propensity score matching. Overall survival to discharge rate did not differ in both groups (4.6% for compliance group vs. 4.5 for non-compliance group, p = 0.78). Adjusted odds ratio of compliance for survival to discharge were 1.12 (95% CI 0.92-1.36). More patients with favorable neurological outcome was shown in compliance group (2.5% vs. 1.7%, p ˂ 0.01) and adjusted odds ratio was 1.91 (95% CI 1.42-2.59). Conclusions: Although survival to discharge rate did not differ for patient with EMS non-compliance with STI protocol, lesser patients survived with favorable neurological outcomes when EMS did not stay for sufficient time on scene in OHCA before transport.