Objective: To examine the prognostic value of serum neuron-specific en
olase for early prediction of outcome in patients at risk for anoxic e
ncephalopathy after cardiac arrest. Design: Prospective study. Setting
: Coronary intensive care unit of the University of Heidelberg. Patien
ts: Forty-three patients (66.8 +/- 12.7 [SD] yrs, range 33 to 85) who
had had either primary or secondary cardiac arrest, followed by cardio
pulmonary resuscitation (CPR). Interventions: Serial blood samples and
clinical examinations. Measurements and Main Results: Serum neuron-sp
ecific enolase concentrations were determined after CPR on 7 consecuti
ve days. Twenty five patients remained comatose and subsequently died;
18 patients survived the first 3 months and had no relevant functiona
l deficit at 3-month follow-up. Neuron-specific enolase concentrations
were correlated with neurologic outcome, Concentrations of >33 ng/mL
predicted persistent coma with a high specificity (100%) and a positiv
e predictive Value of 100%. Overall sensitivity was 80%, with a negati
ve predictive value of 78%. Serum concentrations of neuron specific en
olase exceeded this cutoff value no more than 3 days after cardiac arr
est in 95% of patients in whom these concentrations had exceeded 33 ng
/mL, Conclusions: In patients who have been resuscitated after cardiac
arrest, serum neuron-specific enolase concentrations of >33 ng/mL pre
dict persistent coma with a high specificity. Values below this cutoff
level do not necessarily indicate complete recovery, because this met
hod has a sensitivity of 80%.