Abstract 350: Construction and Validation of a New Termination-of-Resuscitation Rule for Out-of-Hospital Cardiac Arrest in the Japanese Population; JCS-ReSS Study

Abstract

Background: Termination of resuscitation (TOR) rules for OHCA have been constructed for better utilization of hospital healthcare resources and increasing the availability of care for other patients. However, TOR rules in the prehospital settings are not legally implemented in Japan. Thus, almost all OHCA patients are transported to the hospital, regardless to the possibility of successful resuscitation. Objective: To validate the TOR-ALS rule in Japan and to establish a new TOR rule for terminating ongoing resuscitation just after hospital arrival. Methods: Data from a nationwide database of a prospective population-based cohort using an Utstein-style template for OHCA patients during January 2011 to December 2015 was used for the current analysis. We constructed a new TOR rule consisting of 5 factors (no-witness, no-return of spontaneous circulation (ROSC), asystole for the initial rhythm, no-defibrillation before hospital arrival, age>75) including the patients during 2011 to 2013 (derivation cohort). Statistical values to predict death and unfavorable neurological outcome(UNO) at one-month were calculated for the TOR-ALS rule (no-witness, no-bystander CPR, no-ROSC, no-defibrillation) and the new rule, respectively. After constructing the new rule, we validated it in a cohort of patients during 2014 to 2015 (validation cohort). Results: Of the 629,471 patients documented for the study period, 466,033 adult patients with OHCA without external causes of arrest were included in the present analysis. In the derivation cohort, values (PPV/NPV/sensitivity/specificity/AUC-ROC) to predict death for each rule were; TOR-ALS rule (99.35%/6.01%/29.89%/95.87%/0.63), new rule (99.61%/6.53%/34.96%/97.05%/0.66). Values to predict UNO were, TOR-ALS rule (99.90%/3.09%/29.37%/98.75%/0.64), new rule (99.97%/3.34%/34.28%/99.49%/0.67). In the validation cohort, values to predict death were, TOR-ALS rule (99.38%/6.53%/26.97%/96.81%/0.62), new rule (99.66%/7.24%/34.00%/97.79%/0.66). Values to predict UNO were, TOR-ALS rule (99.13%/3.36%/26.43%/99.11%/0.63), new rule (99.98%/3.71%/33.24%/99.75%/0.67). Conclusion: The new TOR rule has a higher PPV and specificity to predict unfavorable outcome of OHCA in a Japanese population.