Prediction of neurological outcome after birth asphyxia from early continuous two-channel electroencephalography

Objective: To determine whether two-channel continuous electroencephalograp hy (EEG) applied within 12 h of birth can predict the severity of neurologi cal complications and neurodevelopmental outcome following birth asphyxia. Methods. A continuous two-channel EEG was performed within 12 h of birth in 22 infants suspected of having suffered birth asphyxia and 11 healthy cont rol infants (22 infants at a general and 11 at a specialist paediatric unit ). Criteria to categorise normal and abnormal EEG records were defined and compared with the severity of hypoxic/ischaemic encephalopathy (HIE) and wi th neurodevelopmental outcome, assessed at or after 12 months of age. Resul ts: EEG recordings were commenced at a median (range) of 2 h 50 min (1 h 45 min to 12 h) after birth. Technically satisfactory recordings were obtaine d in all but one infant. All control infants remained asymptomatic and had a normal EEG with discernible sleep/awake periods. 12 h after birth the EEG was normal in all 12 infants suspected of asphyxia who remained well or de veloped grade I HIE and was abnormal in six of nine infants with grade II o r III HIE. Fifteen of 16 infants suspected of asphyxia with a normal neurod evelopmental outcome had a normal EEG at 12 h; transient abnormalities last ing not more than 8 h had been detected in three of these infants. All five infants who died or developed neurodevelopmental abnormalities had an abno rmal EEG. At 12 h of age the sensitivity, specificity, positive predictive value (PPV); negative predictive value (NPV) and likelihood ratio for predi cting severe (grade II or Iii) HIE were: 67,. 100, 100, 80% and infinity an d for subsequent death or neurodevelopmental impairments: 100, 94, 83, 100 and 16%, respectively.; Assessment of the EEG before 12 h of age altered pr ognostic accuracy: 4 h after birth the sensitivity, specificity, positive a nd negative predictive values and the:likelihood ratio for poor neurodevelo pmental outcome were 100, 71, 33%, 100 and 3.7%, respectively (16 infants). Conclusion: Continuous two-channel EEG: is an accurate tool for assessing the severity of neurological insult soon after birth asphyxia. (C) 1999 Els evier Science Ireland Ltd. All rights reserved.