The prognostic value of early aEEG in asphyxiated infants undergoing systemic hypothermia treatment

BACKGROUND: Induced moderate hypothermia (HT) for 72 h has been shown to reduce the combined outcome of death or severe neurodevelopmental disabilities in asphyxiated full-term infants. A pathological amplitude integrated EEG background as early as 3-6 h after birth, has been shown to correlate to poor prognosis. AIM: The aim of this study was to investigate the correlation between amplitude integrated EEG during HT treatment and short-term outcome in asphyxiated full-term infants with moderate/severe hypoxic-ischaemic encephalopathy. METHODS: Between December 2006 and December 2007, 24 infants were treated with moderate HT (33.5 degrees C for 72 h) using a cooling mattress. Motor functions were assessed at 4 and 12 months of age. RESULTS: Of the total birth cohort of 28,837 infants, 26 infants fulfilled the criteria for HT treatment (0.9/1000) of whom 23 was treated with HT and all of these infants had available amplitude integrated EEG data. Normal 1-year outcome was found in 10/15 infants with severely abnormal burst-suppression pattern or worse at 6 h of age. Severe abnormalities were found to be significantly predictive for abnormal outcome after 36 h. CONCLUSION: Among asphyxiated infants treated with HT, only those who had aEEG abnormalities persisting at and beyond 24 h after birth showed poor neurological outcome at 1 year.