ABSTRACT
Background: Proper prognostication is critical in clinical decision-making following out-of-hospital cardiac arrest (OHCA). However, only a few prognostic tools with reliable accuracy are available within the first 24 h after admission. Aim: To test the value of neuron-specific enolase (NSE) and S100B protein measurements at admission as early biomarkers of poor prognosis after OHCA. Methods: We enrolled 82 consecutive patients with OHCA who were unconscious when admitted. NSE and S100B levels were measured at admission, and routine blood tests were performed. Death and poor neurological status at discharge were considered as poor clinical outcomes. We evaluated the optimal cut-off levels for NSE and S100B using logistic regression and receiver operating characteristic (ROC) analyses. Results: High concentrations of both biomarkers at admission were significantly associated with an increased risk of poor clinical outcome (NSE: odds ratio [OR] 1.042 per 1 ng/dL, [1.007−1.079; p = 0.004]; S100B: OR 1.046 per 50 pg/mL [1.004−1.090; p < 0.001]). The dual-marker approach with cut-off values of ≥27.6 ng/mL and ≥696 ng/mL for NSE and S100B, respectively, identified patients with poor clinical outcomes with 100% specificity. Conclusions: The NSE and S100B-based dual-marker approach allowed for early discrimination of patients with poor clinical outcomes with 100% specificity. The proposed algorithm may shorten the time required to establish a poor prognosis and limit the volume of futile procedures performed.
ABSTRACT
BACKGROUND: Neuron-specific enolase (NSE) is a biomarker for neurological outcomes after cardiac arrest with the most evidence collected thus far; however, recommended prognostic cutoff values are lacking owing to the discrepancies in the published data. AIMS: The aim of the study was to establish NSE cutoff values for prognostication in the environment of a cardiac intensive care unit following out-of-hospital cardiac arrest (OHCA). METHODS: A consecutive series of 82 patients admitted after OHCA were enrolled. Blood samples for the measurement of NSE levels were collected at admission and after 1 hour, 3, 12, 24, 48, and 72 hours. Neurological outcomes were quantified using the cerebral performance category (CPC) index. Each patient was classified into either the good (CPC ≤2) or poor prognosis (CPC ≥3) group. RESULTS: Median NSE concentrations were higher in the poor prognosis group, and the difference reached statistical significance at 48 and 74 hours (84.4 ng/ml vs 22.9 ng/ml at 48 hours and 152.1 ng/ml vs 18.7 ng/ml at 72 hours; P <0.001, respectively). Moreover, in the poor prognosis group, NSE increased significantly between 24 and 72 hours (P <0.001). NSE cutoffs for the prediction of poor prognosis after OHCA were 39.8 ng/ml, 78.7 ng/ml, and 46.2 ng/ml for 24, 48, and 72 hours, respectively. The areas under the curve were significant at each time point, with the highest values at 48 and 72 hours after admission (0.849 and 0.964, respectively). CONCLUSIONS: Elevated NSE concentrations with a rise in levels in serial measurements may be utilized in the prognostication algorithm after OHCA.
