Abstracts

Rationale: Hypoxic ischemic encephalopathy (HIE) is a significant cause of long term disabilities in newborns. Early recognition of outcome can help in family and medical decision making. Background EEG and amplitude-integrated EEG patterns have been shown to predict either good or poor neurodevelopmental outcomes within 36 hours of life. Objective: To examine if there is a graded relationship between ACNS EEG background rating terminology and MRI pattern of injury in term neonates with HIE undergoing therapeutic hypothermia. Methods: Between 2009-2016, 85 newborns underwent therapeutic hypothermia at our tertiary level IV neonatal ICU. EEG background was blindly scored at onset of EEG recording (T0), 12 hours of life (HOL) (T12), 24 HOL (T24), and 60 HOL (T60). The EEG background was categorized into six patterns using ACNS neonatal EEG terminology: 1-Continuous with or without state change, 2-Discontinuous normal for age with or without state change, 3-Excessively discontinuous with state change, 4- Excessively discontinuous without state change, 5-Low voltage suppression or burst suppression or inactive, 6-Status epilepticus. EEG background continuity/amplitude was rated in the first hour of each time point. State changes were rated for the first three hours after each time point.  Brain MRI were blindly scored using the Barkovich system (Barkovich et al, AJNR 1998) for basal ganglia (BG, 0-4 scale), white matter (WM, 0-5 scale) or combined BG/WS injury (0-4 scale). Results: Of 85 neonates, 11 died without a brain MRI.  Average gestational age was 38.6 (range 34-43) weeks, 43(58%) were male, and mean birth weight was 3.24±0.64 kg. 48 (65%) were born by Cesarean section with mean initial pH of 6.95+ 0.19 and base deficit 18.67 + 4.91, median Apgar score at 5 and 10 minutes of life was 4 (range 0-9) and 5 (range 0-9), respectively. EEG recording began at a median 11.6 HOL (range 4-21 HOL); and therefore, there were 44 recordings at T0, 30 at T12, and 73 recordings at T24 and T60. EEG background at T0 and T24 predicted MRI injury pattern based on the BG (p=0.039 and 0.001, respectively) and the combined BG/WS Barkovich scores (p=0.006 and p Conclusions: ACNS categorization of EEG background at 24 HOL showed correlation with degree of MRI injury in newborns undergoing therapeutic hypothermia. Further study is needed to determine if this scale predicts neurodevelopmental outcome in this population. Funding: None