BACKGROUND: Hyperacute hepatic failure (HHF) has a high mortality rate that is most commonly due to severe cerebral edema. However, brain swelling and marked clinical and EEG suppression are potentially reversible, even though the same findings are associated with a very poor neurological outcome in anoxic-ischemic encephalopathy. METHODS: We present three cases that illustrate neurological recovery despite severe brain swelling and loss of EEG activity. RESULTS: All patients recovered conscious awareness, including one who transiently lost cranial nerve reflexes. CONCLUSIONS: Despite deep coma, markedly suppressed EEG and brain edema, aggressive control of ICP may lead to good recovery in acute hepatic failure.