Prediction of neurological outcome after cardiopulmonary resuscitation by serial determination of serum neuron-specific enolase

Aims Data on the diagnostic accuracy of neuron-specific enolase (NSE) as marker of hypoxic brain damage are conflicting. The purpose of this prospective observational cohort study was to explore the prognostic value of serum NSE after cardiopulmonary resuscitation (CPR) and to define the most sensitive cutoff value with a specificity of 100% for the prediction of persistent coma. Methods and results Serum NSE concentrations were serially determined in 227 consecutive unconscious patients after CPR who were classified according to the best Glasgow-Pittsburgh cerebral performance categories (CPC, 1-4) achieved within 6 months follow-up. Sixteen patients were excluded due to incomplete NSE data and 34 due to death under analgesia sedation. The prevalence of poor neurological outcome (persistent coma, CPC 4) in our 177 analysed patients was 33%. At a specificity of 100%, a peak NSE concentration above 80 ng/mL predicted persistent coma with a sensitivity of 63%, a positive predictive value of 100%, a negative predictive value of 84%, and a predictive accuracy of 88%. Conclusion A peak serum NSE concentration exceeding 80 ng/mL is a highly specific but only moderately sensitive marker for a poor neurological outcome after CPR.