Early serial EEG in hypoxic ischaemic encephalopathy

Objectives: To perform early serial EEGs in infants with hypoxic ischaemic encephalopathy (HIE) and compare the findings with neurodevelopmental outco me. Methods: Nine full-term neonates with HIE had simultaneous video-EEG polygr aphic studies within 8 h of birth. The EEG was repeated at 12-24 h interval s. All surviving infants had a neurodevelopmental assessment at 1 year. Results: Two infants had a normal or mildly abnormal EEG within 8 h of birt h and neurodevelopmental outcome was normal. Seven infants had severely dep ressed background activity in the first 8 h of life. In 3 infants the EEG a ctivity recovered within 12-24 h showing continuous activity with no or onl y minor abnormalities. All these infants had a normal outcome. The remainin g 4 infants, who also had an initially inactive recording, subsequently dev eloped severe background abnormalities. At follow-up, two infants had died and the remainder developed major neurological sequelae. Conclusions: Early EEG is an excellent prognostic indicator for a favourabl e outcome if normal within the first 8 h of life and for a poor outcome if the background activity continues to be inactive or grossly abnormal beyond 8-12 h of life. However, an inactive or very depressed EEG within the firs t 8 h of life can be associated with good outcome if the EEG activity recov ers within 12 h. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved .