title: Automated auditory mismatch negativity paradigm improves coma prognostic accuracy after cardiac arrest and therapeutic hypothermia.
abstract: OBJECTIVE
  EEG and somatosensory evoked potential are highly predictive of poor outcome after cardiac arrest; their accuracy for good recovery is however low. We evaluated whether addition of an automated mismatch negativity-based auditory discrimination paradigm (ADP) to EEG and somatosensory evoked potential improves prediction of awakening.
  
  
  METHODS
  EEG and ADP were prospectively recorded in 30 adults during therapeutic hypothermia and in normothermia. We studied the progression of auditory discrimination on single-trial multivariate analyses from therapeutic hypothermia to normothermia, and its correlation to outcome at 3 months, assessed with cerebral performance categories.
  
  
  RESULTS
  At 3 months, 18 of 30 patients (60%) survived; 5 had severe neurologic impairment (cerebral performance categories = 3) and 13 had good recovery (cerebral performance categories = 1-2). All 10 subjects showing improvements of auditory discrimination from therapeutic hypothermia to normothermia regained consciousness: ADP was 100% predictive for awakening. The addition of ADP significantly improved mortality prediction (area under the curve, 0.77 for standard model including clinical examination, EEG, somatosensory evoked potential, versus 0.86 after adding ADP, P = 0.02).
  
  
  CONCLUSIONS
  This automated ADP significantly improves early coma prognostic accuracy after cardiac arrest and therapeutic hypothermia. The progression of auditory discrimination is strongly predictive of favorable recovery and appears complementary to existing prognosticators of poor outcome. Before routine implementation, validation on larger cohorts is warranted.
authors.affiliation: *Department of Clinical Neurosciences, CHUV and University of Lausanne, Lausanne, Switzerland; †EEG Brain Mapping Core, Center for Biomedical Imaging (CIBM), CHUV and University of Lausanne, Lausanne, Switzerland; Departments of ‡Radiology and §Intensive Care Medicine, CHUV and University of Lausanne, Lausanne, Switzerland.
authors.forename: Andrea O
authors.initials: AO
authors.lastname: Rossetti
authors.forename: Athina
authors.initials: A
authors.lastname: Tzovara
authors.forename: Micah M
authors.initials: MM
authors.lastname: Murray
authors.forename: Marzia
authors.initials: M
authors.lastname: De Lucia
authors.forename: Mauro
authors.initials: M
authors.lastname: Oddo
mesh_terms: D000161:Acoustic Stimulation; D000368:Aged; D000465:Algorithms; D003128:Coma / Q000175:diagnosis* / Q000209:etiology*; D003265:Contingent Negative Variation / Q000502:physiology*; D005260:Female; D006323:Heart Arrest / Q000150:complications* / Q000628:therapy*; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies