TY - JOUR
T1 - Falsely pessimistic prognosis by EEG in post-anoxic coma after cardiac arrest
T2 - the borderland of nonconvulsive status epilepticus
AU - Sreedharan, Jemeen
AU - Gourlay, Elizabeth
AU - Evans, Matthew R
AU - Koutroumanidis, Michalis
PY - 2012/9
Y1 - 2012/9
N2 - BACKGROUND: Prognostication following anoxic coma relies on clinical assessment and is assisted by neurophysiology. A non-evolving EEG spike burst/isoelectric suppression pattern after the first 24 hours almost invariably indicates poor outcome, while an evolving pattern implies nonconvulsive status epilepticus (NCSE) that may "hide" surviving brain activity and is amenable to treatment.CASE STUDY: We present the case of a 53-year-old woman who had a witnessed out-of-hospital ventricular fibrillation cardiac arrest, was resuscitated by paramedics, but remained comatose. An EEG, performed 36 hours post-insult, showed an unremitting, non-evolving, unresponsive 2-6 Hz high-voltage spike burst/isoelectric suppression pattern, which remained unchanged at 96 hours post-insult, following therapeutic hypothermia. During this period, she was completely off sedation and taking triple antiepileptic treatment, without systemic confounding disorders. Although the initial pattern was indicative of poor neurological outcome, she eventually made meaningful functional recovery; the last EEG showed satisfactory background rhythms and stimulus-induced epileptiform discharges without seizures.CONCLUSION: In post-anoxic coma, non-evolving >2 Hz spike burst/isoelectric suppression pattern may still reflect NCSE and therefore should be considered in the diagnostic EEG criteria for NCSE. Such borderline patterns should not dissuade physicians from intensifying treatment until more confident prognostication can be made.
AB - BACKGROUND: Prognostication following anoxic coma relies on clinical assessment and is assisted by neurophysiology. A non-evolving EEG spike burst/isoelectric suppression pattern after the first 24 hours almost invariably indicates poor outcome, while an evolving pattern implies nonconvulsive status epilepticus (NCSE) that may "hide" surviving brain activity and is amenable to treatment.CASE STUDY: We present the case of a 53-year-old woman who had a witnessed out-of-hospital ventricular fibrillation cardiac arrest, was resuscitated by paramedics, but remained comatose. An EEG, performed 36 hours post-insult, showed an unremitting, non-evolving, unresponsive 2-6 Hz high-voltage spike burst/isoelectric suppression pattern, which remained unchanged at 96 hours post-insult, following therapeutic hypothermia. During this period, she was completely off sedation and taking triple antiepileptic treatment, without systemic confounding disorders. Although the initial pattern was indicative of poor neurological outcome, she eventually made meaningful functional recovery; the last EEG showed satisfactory background rhythms and stimulus-induced epileptiform discharges without seizures.CONCLUSION: In post-anoxic coma, non-evolving >2 Hz spike burst/isoelectric suppression pattern may still reflect NCSE and therefore should be considered in the diagnostic EEG criteria for NCSE. Such borderline patterns should not dissuade physicians from intensifying treatment until more confident prognostication can be made.
KW - EEG
KW - False prediction
KW - Nonconvulsive status
KW - Post-anoxic coma
KW - Repetitive epileptiform discharges
UR - http://www.scopus.com/inward/record.url?scp=84867410857&partnerID=8YFLogxK
U2 - 10.1684/epd.2012.0519
DO - 10.1684/epd.2012.0519
M3 - Article
C2 - 22940145
SN - 1294-9361
VL - 14
SP - 340
EP - 344
JO - EPILEPTIC DISORDERS
JF - EPILEPTIC DISORDERS
IS - 3
ER -