title: Neuron-specific enolase correlates with other prognostic markers after cardiac arrest.
abstract: OBJECTIVE
  Therapeutic hypothermia (TH) is a recommended treatment for survivors of cardiac arrest. Prognostication is complicated since sedation and muscle relaxation are used and established indicators of a poor prognosis are lacking. This prospective, observational study describes the pattern of commonly used prognostic markers in a hypothermia-treated cohort of cardiac arrest patients with prolonged coma.
  
  
  METHODS
  Among 111 consecutive patients, 19 died, 58 recovered, and 34 were in coma 3 days after normothermia (4.5 days after cardiac arrest), defined as prolonged coma. All patients were monitored with continuous amplitude-integrated EEG and repeated samples of neuron-specific enolase (NSE) were collected. In patients with prolonged coma, somatosensory evoked potentials (SSEP) and brain MRI were performed. A postmortem brain investigation was undertaken in patients who died.
  
  
  RESULTS
  Six of the 17 patients (35%) with NSE levels <33 μg/L at 48 hours regained the capacity to obey verbal commands. By contrast, all 17 patients with NSE levels >33 failed to recover consciousness. In the >33 NSE group, all 10 studied with MRI had extensive brain injury on diffusion-weighted images, 12/16 lacked cortical responses on SSEP, and all 6 who underwent autopsy had extensive severe histologic damage. NSE levels also correlated with EEG pattern, but less uniformly, since 11/17 with NSE <33 had an electrographic status epilepticus (ESE), only one of whom recovered. A continuous EEG pattern correlated to NSE <33 and awakening.
  
  
  CONCLUSIONS
  NSE correlates well with other markers of ischemic brain injury. In patients with no other signs of brain injury, postanoxic ESE may explain a poor outcome.
authors.affiliation: Division of Neurology, Department of Clinical Sciences, Skåne University Hospital, Lund University, Lund, Sweden. tobias.cronberg@skane.se
authors.forename: T
authors.initials: T
authors.lastname: Cronberg
authors.forename: M
authors.initials: M
authors.lastname: Rundgren
authors.forename: E
authors.initials: E
authors.lastname: Westhall
authors.forename: E
authors.initials: E
authors.lastname: Englund
authors.forename: R
authors.initials: R
authors.lastname: Siemund
authors.forename: I
authors.initials: I
authors.lastname: Rosén
authors.forename: H
authors.initials: H
authors.lastname: Widner
authors.forename: H
authors.initials: H
authors.lastname: Friberg
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D016887:Cardiopulmonary Resuscitation; D003128:Coma / Q000097:blood / Q000175:diagnosis*; D005260:Female; D006323:Heart Arrest / Q000097:blood* / Q000175:diagnosis* / Q000628:therapy; D006801:Humans; D007036:Hypothermia, Induced; D008297:Male; D008875:Middle Aged; D010751:Phosphopyruvate Hydratase / Q000097:blood*; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies
chemical_list: D015415:Biomarkers; D010751:Phosphopyruvate Hydratase