Predictors of awakening from postanoxic status epilepticus after therapeutic hypothermia.
BACKGROUND
Postanoxic status epilepticus (PSE) is considered a predictor of fatal outcome and therefore not intensively treated; however, some patients have had favorable outcomes. The aim of this study was to identify favorable predictors for awakening beyond vegetative state in PSE.


METHODS
We studied six subjects treated with hypothermia improving beyond vegetative state after cerebral anoxia, despite PSE. They were among a cohort of patients treated for anoxic encephalopathy with therapeutic hypothermia in our institution between October 1999 and May 2006 (retrospectively, 3/107 patients) and June 2006 and May 2008 (prospectively, 3/74 patients). PSE was defined by clinical and EEG criteria. Outcome was assessed according to the Glasgow-Pittsburgh Cerebral Performance Categories (CPC).


RESULTS
All improving patients had preserved brainstem reflexes, cortical somatosensory evoked potentials, and reactive EEG background during PSE. Half of them had myoclonic PSE, while three had nonconvulsive PSE. In the prospective arm, 3/28 patients with PSE showed this clinical-electrophysiologic profile; all awoke. Treatments consisted of benzodiazepines, various antiepileptic drugs, and propofol. One subject died of pneumonia in a minimally conscious state, one patient returned to baseline (CPC1), three had moderate impairment (CPC2), and one remained dependent (CPC3). Patients with nonconvulsive PSE showed a better prognosis than subjects with myoclonic PSE (p = 0.042).


CONCLUSIONS
Patients with postanoxic status epilepticus and preserved brainstem reactions, somatosensory evoked potentials, and EEG reactivity may have a favorable outcome if their condition is treated as status epilepticus.
Rossetti
Andrea O
AO
Service de Neurologie, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland. andrea.rossetti@chuv.ch
Oddo
Mauro
M
Liaudet
Lucas
L
Kaplan
Peter W
PW
D000368:Aged; D000927:Anticonvulsants / Q000627:therapeutic use; D001569:Benzodiazepines / Q000627:therapeutic use; D001933:Brain Stem / Q000503:physiopathology; D002540:Cerebral Cortex / Q000503:physiopathology; D015331:Cohort Studies; D003243:Consciousness; D004569:Electroencephalography; D004831:Epilepsies, Myoclonic / Q000150:complications; D005073:Evoked Potentials, Somatosensory; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000627:therapeutic use; D007036:Hypothermia, Induced; D002534:Hypoxia, Brain / Q000150:complications*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015742:Propofol / Q000627:therapeutic use; D011446:Prospective Studies; D013226:Status Epilepticus / Q000209:etiology / Q000503:physiopathology / Q000523:psychology* / Q000628:therapy*; D016896:Treatment Outcome
D000927:Anticonvulsants; D006993:Hypnotics and Sedatives; D001569:Benzodiazepines; D015742:Propofol