The following is a summary of “Prediction of the neurological outcomes post-cardiac arrest: A prospective validation of the CAST and rCAST,” published in the January 2024 issue of Emergency Medicine by Kikutani, et al.

Despite achieving the return of spontaneous circulation (ROSC) after out-of-hospital cardiac arrest (OHCA), patients’ neurological prognosis remains grim. For a study, researchers sought to validate externally and prospectively two scoring systems developed for predicting neurological outcomes in OHCA patients undergoing targeted temperature management (TTM): the CAST score and its simplified version, the revised CAST (rCAST) score.

Conducted as a prospective, multicenter, observational study, data were collected from the SOS KANTO 2017 registry, which encompasses OHCA cases across hospitals in the Kanto region, Japan. The primary outcome measured was a favorable neurological outcome (Cerebral Performance Category score of 1 or 2) at 30 days, with secondary outcomes including a favorable neurological outcome at 90 days and survival at 30 and 90 days. Predictive accuracies of both the original CAST (oCAST) and rCAST scores were assessed using the area under the receiver operating characteristic curve (AUC).

Among 9,909 OHCA patients, 565 achieved ROSC and underwent TTM, with 259 patients included in the analysis. The AUCs for predicting favorable neurological outcomes at 30 days were 0.86 for oCAST and 0.87 for rCAST, and at 90 days were 0.87 for oCAST and 0.88 for rCAST. The rCAST demonstrated superior predictive accuracy compared to the NULL-PLEASE score. Patients with favorable neurological outcomes in the high severity group by rCAST tended to present with hypothermia upon hospital arrival and the absence of loss of gray-white matter differentiation on brain CT. Neurological function at 90 days significantly correlated with rCAST scores (r = 0.63, P < 0.001).

The rCAST score exhibited a high predictive accuracy for neurological prognosis in OHCA patients undergoing TTM, similar to the performance of the oCAST score. Moreover, rCAST scores strongly correlated with neurological function at 90 days, suggesting its utility in assessing the severity of brain injury post-cardiac arrest.

Reference: sciencedirect.com/science/article/abs/pii/S0735675723005697