Prediction of Future Seizures in Neonates Who Received Selective Head Cooling for HIE (P1.347)

OBJECTIVE: We aimed to identify clinical, MRI, and EEG features from the neonatal period that predict the development of seizures before age 2 in neonates who underwent therapeutic hypothermia (TH) for hypoxic-ischemic encephalopathy (HIE). BACKGROUND: HIE is a major cause of neurological morbidity in neonates, including cerebral palsy, cognitive impairment, and epilepsy. TH improves motor outcomes in term infants with HIE, but epilepsy outcomes are not well described. DESIGN/METHODS: Retrospective review was performed on term neonates who underwent TH. Subjects were monitored on cEEG after the 72-hour cooling period, and had an MRI at 7-10 days. Those without 2 year follow up were excluded. A multivariable logistic regression model identified risk factors for the development of epilepsy, using clinical features, chart EEG data at 72 hours, and details from brain MRI, using variable selection with the “best subsets” method. RESULTS: 49 infants had 2-year follow up data. Of these, 9 developed epilepsy after the neonatal period. In bivariate analysis, initial pH ≤ 6.8 (p = 0.03, OR [95% CI] 10.8 [1.2,95]), MRI injury to thalamus (p = 0.006, OR 15.2 [2.2, 105]), and basal ganglia (p = 0.001, OR 20 [3.3,120]) were significantly associated with seizures before age 2. Multivariable analysis found pH <6.8 (p = 0.03, adjusted OR 31 [1.4,660]), cEEG with burst suppression pattern (p = 0.04, adjusted OR 20.2 [1.2,333]), and MRI with basal ganglia injury (p = 0.004, adjusted OR 57 [3.7,863]) were predictive factors of significance. The predictive model found a low-risk and high-risk group for the development of epilepsy. In the low-risk group, 1/37 neonates developed seizures vs 8/12 neonates in the high-risk group. CONCLUSIONS: This model predicts that neonates with HIE who undergo TH are at greatest risk of epilepsy if they fall into a high-risk group with 2-3 identified risk factors. This classification of risk will help direct close follow-up of development of epilepsy in this population. Disclosure: Dr. Paolicchi has received research support from Lundbeck Research USA, Inc. Dr. Das has nothing to disclose. Dr. Engel has nothing to disclose. Dr. Perlman has nothing to disclose. Dr. Grinspan has nothing to disclose.