A prognostic score may be effective in predicting neurologic outcomes in patients who have experienced an out-of-hospital cardiac arrest, according to a recent study.
In the study, published in Scientific Reports, investigators conducted a comprehensive validation of several prognostic scoring systems for predicting neurological outcomes in patients who experienced an out-of-hospital cardiac arrest (OOHCA). Utilizing data from a nationwide multicenter registry in Japan, the researchers compared the accuracy of five prognostic scores: Out-of-Hospital Cardiac Arrest (OHCA), Cardiac Arrest Hospital Prognosis (CAHP), revised post–Cardiac Arrest Syndrome for Therapeutic Hypothermia (rCAST), MIRACLE2, and the Nonshockable rhythm, Unwitnessed arrest, Long no-flow or Long low-flow period, blood PH < 7.2, Lactate > 7.0 mmol/L, End-stage chronic kidney disease on dialysis, Age ≥ 85 years, Still resuscitation, and Extracardiac cause (NULL-PLEASE).
The investigators analyzed the data of 11,924 hospitalized adult patients, selected from an original group of 56,537 OOHCA cases. The patients were excluded if they were under 18 years, had an unknown initial heart rhythm, achieved immediate return of spontaneous circulation when emergency medical services arrived, or had an unknown prognosis at 1 month. The primary endpoint of the study was the prediction of favorable neurologic outcomes at 30 days post–cardiac arrest, as measured by a cerebral performance category scale of 1 or 2.
The NULL-PLEASE score demonstrated the highest area under the curve (AUC) of 0.831 among the prognostic tools evaluated, indicating its effectiveness in predicting neurologic outcomes in this patient population. However, the study also found that the CAHP score was nearly as accurate, with both NULL-PLEASE and CAHP scores significantly outperforming the other scores in predicting favorable outcomes. This indicated both scores’ effectiveness in identifying patients with favorable neurologic outcomes. These two scores were significantly more accurate compared with the other systems.
The AUC values for the various prognostic scores in predicting favorable neurologic outcomes at 30 days were 0.713 for OHCA, 0.727 for MIRACLE2, and 0.761 for rCAST.
The distribution of patients among the various score categories differed. For instance, the CAHP and NULL-PLEASE scores had distributions that were close to normal, whereas the rCAST and OHCA scores were more heavily weighted toward categories with lower predicted rates of favorable outcomes. Additionally, the investigators employed partial AUCs to assess the ability of the scores to distinguish outcomes within ranges of high specificity (0.8–1.0) and high sensitivity (0.8–1.0). The NULL-PLEASE score demonstrated a notably higher partial AUC in both areas when compared with the other scores, indicating its utility in various clinical situations where precise prognostication is critical.
The clinical utility of the NULL-PLEASE score, because of its comprehensive and easily applicable criteria, may serve as an effective tool for prognostication in a diverse OOHCA patient population. However, the investigators recognized that its validation was conducted within the context of the Japanese emergency system, which could affect the applicability of the findings to other populations. Additionally, variations in patient populations and target groups from the original studies for each score may have impacted the validation outcomes.
Full disclosures can be found in the published study.