title: Standardized EEG interpretation accurately predicts prognosis after cardiac arrest.
abstract: OBJECTIVE
  To identify reliable predictors of outcome in comatose patients after cardiac arrest using a single routine EEG and standardized interpretation according to the terminology proposed by the American Clinical Neurophysiology Society.
  
  
  METHODS
  In this cohort study, 4 EEG specialists, blinded to outcome, evaluated prospectively recorded EEGs in the Target Temperature Management trial (TTM trial) that randomized patients to 33°C vs 36°C. Routine EEG was performed in patients still comatose after rewarming. EEGs were classified into highly malignant (suppression, suppression with periodic discharges, burst-suppression), malignant (periodic or rhythmic patterns, pathological or nonreactive background), and benign EEG (absence of malignant features). Poor outcome was defined as best Cerebral Performance Category score 3-5 until 180 days.
  
  
  RESULTS
  Eight TTM sites randomized 202 patients. EEGs were recorded in 103 patients at a median 77 hours after cardiac arrest; 37% had a highly malignant EEG and all had a poor outcome (specificity 100%, sensitivity 50%). Any malignant EEG feature had a low specificity to predict poor prognosis (48%) but if 2 malignant EEG features were present specificity increased to 96% (p < 0.001). Specificity and sensitivity were not significantly affected by targeted temperature or sedation. A benign EEG was found in 1% of the patients with a poor outcome.
  
  
  CONCLUSIONS
  Highly malignant EEG after rewarming reliably predicted poor outcome in half of patients without false predictions. An isolated finding of a single malignant feature did not predict poor outcome whereas a benign EEG was highly predictive of a good outcome.
authors: Authors' affiliations are listed at the end of the article. erik.westhall@med.lu.se.
authors: Erik
authors: E
authors: Westhall
authors: Authors' affiliations are listed at the end of the article.
authors: Andrea O
authors: AO
authors: Rossetti
authors: Authors' affiliations are listed at the end of the article.
authors: Anne-Fleur
authors: AF
authors: van Rootselaar
authors: Authors' affiliations are listed at the end of the article.
authors: Troels
authors: T
authors: Wesenberg Kjaer
authors: Authors' affiliations are listed at the end of the article.
authors: Janneke
authors: J
authors: Horn
authors: Authors' affiliations are listed at the end of the article.
authors: Susann
authors: S
authors: Ullén
authors: Authors' affiliations are listed at the end of the article.
authors: Hans
authors: H
authors: Friberg
authors: Authors' affiliations are listed at the end of the article.
authors: Niklas
authors: N
authors: Nielsen
authors: Authors' affiliations are listed at the end of the article.
authors: Ingmar
authors: I
authors: Rosén
authors: Authors' affiliations are listed at the end of the article.
authors: Anders
authors: A
authors: Åneman
authors: Authors' affiliations are listed at the end of the article.
authors: David
authors: D
authors: Erlinge
authors: Authors' affiliations are listed at the end of the article.
authors: Yvan
authors: Y
authors: Gasche
authors: Authors' affiliations are listed at the end of the article.
authors: Christian
authors: C
authors: Hassager
authors: Authors' affiliations are listed at the end of the article.
authors: Jan
authors: J
authors: Hovdenes
authors: Authors' affiliations are listed at the end of the article.
authors: Jesper
authors: J
authors: Kjaergaard
authors: Authors' affiliations are listed at the end of the article.
authors: Michael
authors: M
authors: Kuiper
authors: Authors' affiliations are listed at the end of the article.
authors: Tommaso
authors: T
authors: Pellis
authors: Authors' affiliations are listed at the end of the article.
authors: Pascal
authors: P
authors: Stammet
authors: Authors' affiliations are listed at the end of the article.
authors: Michael
authors: M
authors: Wanscher
authors: Authors' affiliations are listed at the end of the article.
authors: Jørn
authors: J
authors: Wetterslev
authors: Authors' affiliations are listed at the end of the article.
authors: Matt P
authors: MP
authors: Wise
authors: Tobias
authors: T
authors: Cronberg
mesh_terms: D000368:Aged; D000927:Anticonvulsants / Q000627:therapeutic use; D001831:Body Temperature; D001921:Brain / Q000503:physiopathology*; D015897:Comorbidity; D004569:Electroencephalography; D005260:Female; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000175:diagnosis* / Q000503:physiopathology* / Q000628:therapy; D006801:Humans; D006993:Hypnotics and Sedatives / Q000627:therapeutic use; D007036:Hypothermia, Induced; D008297:Male; D011379:Prognosis; D012640:Seizures / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D016037:Single-Blind Method; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000927:Anticonvulsants; D006993:Hypnotics and Sedatives