Validation of neuron-specific enolase in cardiac arrest patients with limited withdrawal of life-sustaining therapy

AimWe validated the prognostic performance of neuron-specific enolase (NSE) according to the recommended values in cardiac arrest (CA) survivors.MethodsWe analyzed the data of adult CA survivors who underwent targeted temperature management between January 2014 and December 2020. We measured the NSE level 48 h and 72 h after CA. We performed receiver operating characteristics (ROC) and used the reference value (17 μg/L) and the guidelines-suggested value (60 μg/L) as thresholds. The primary outcome was 6-month neurological outcomes with Cerebral Performance Category (CPC), dichotomized into good (CPC 1 or 2) or poor (CPC 3–5).ResultsOf the 513 included patients, 346 (67.4 %) patients had poor neurological outcomes. The area under ROC (AUC) of NSE at 48 h was 0.887 (95 % confidence intervals [CIs], 0.851–0.909) with the Youden index of 35.6 μg/L. A false positive rate (FPR) of <2 % was observed (54.1 μg/L). The thresholds values (17, 60) had a sensitivity of 86.1% and 56.7 % and a specificity of 66.7%and 98.8 %, respectively. The AUC of NSE at 72 h was 0.892 (95 % CIs, 0.849–0.920) with the Youden index of 30.4 μg/L. The threshold values (17, 60) had a sensitivity of 86.0%and 59.4 % with a specificity of 72.2%and 98.3 %, respectively. An FPR of <2 % was observed (53.6 μg/L). Among the 156 patients and 113 patients with NSE at 48 h and at 72 h ≤ 17 μg/L, respectively, 109 and 83 patients had good neurological outcomes.ConclusionsThe cut-off value of NSE (60 μg/L) was acceptable to predict poor neurological outcomes with an FPR <2 % in cardiac arrest survivors, irrespective of at 48 or 72 h. NSE (17 μg/L) can function as mitigating factor to deter early WLST.