Etiology and prognosis of alpha coma.
We reviewed our experience with alpha coma, the finding of predominantly alpha-frequency rhythms in the EEGs of unconscious patients, and identified 50 patients. Cardiac arrest, either inside (n = 25) or outside (n = 24) the hospital, was the cause of unconsciousness in all except one patient who had hyperglycemic, hyperosmolar coma. After out-of-hospital cardiac arrest, the risk of never regaining consciousness or dying during hospitalization did not differ significantly between unconscious patients with (n = 24) and without (n = 69) alpha frequencies in their EEGs. A review of the literature supports our findings that alpha coma most commonly follows cardiac arrest and does not preclude the possibility of neurologic recovery. We conclude that alpha coma is a descriptive term and lacks prognostic significance in itself.
Austin
E J
EJ
Department of Medicine, University of Washington School of Medicine, Seattle.
Wilkus
R J
RJ
Longstreth
W T
WT
D000513:Alpha Rhythm; D003128:Coma / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology; D004569:Electroencephalography; D006323:Heart Arrest / Q000150:complications; D006760:Hospitalization; D006801:Humans; D011379:Prognosis