Cerebrospinal fluid creatine kinase activity and neurologic recovery after cardiac arrest.

We evaluated prospectively the relation between cerebrospinal fluid creatine kinase activity (CSF CK) and neurologic recovery after out-of-hospital cardiac arrest. Without knowledge of the enzyme results, we determined whether patients awoke, followed commands, or had comprehensible speech. CSF CK was significantly higher in never-awakening than in awakening patients. After cardiac arrest, elevation of CSF CK predicts poor neurologic recovery.