Early discontinuation of antiseizure medications in neonates with hypoxic-ischemic encephalopathy

Abstract

Objective: Neonates with hypoxic-ischemic encephalopathy (HIE) managed with therapeutic hypothermia (TH) often experience acute symptomatic seizures, prompting treatment with antiseizure medications (ASMs). Because the risk of seizure occurrence after hospital discharge is unknown, the optimal ASM treatment duration is unclear. We aimed to determine the risk of seizure occurrence after hospital discharge and the impact of ASM treatment duration on this outcome.

Methods: We performed a single-center, retrospective study of consecutive neonates with HIE managed with TH who received ASMs for acute symptomatic seizures from June 2010 through December 2014. Neonates were monitored with continuous electroencephalography (EEG) during TH.

Results: Follow-up data were available for 59 (82%) of 72 neonates who survived to discharge, with a median follow-up period of 19 months (interquartile range [IQR] 11-25). Acute symptomatic seizures occurred in 35 neonates (59%), including electrographic seizures in 21 neonates (36%). ASMs were continued upon discharge in 17 (49%) of 35 neonates. Seizures occurred in follow-up in four neonates (11%). No patient for whom ASMs were discontinued prior to discharge experienced seizures during the follow-up period.

Significance: Among neonates with HIE, seizures after hospital discharge were rare in those with acute symptomatic seizures and did not occur in neonates without acute symptomatic seizures. ASM discontinuation prior to discharge did not increase the risk of seizures during the follow-up period, suggesting that ASMs may be discontinued in many neonates prior to discharge.

Keywords: Antiseizure medication; Hypoxic-ischemic encephalopathy; Neonatal seizures; Outcomes; Therapeutic hypothermia.

Figure 1

Study Design. Eighty-one neonates were eligible and 59 had follow-up data available. Thirty-five neonates experienced acute symptomatic seizures, while 24 did not. Of those with acute symptomatic seizures, 4 had seizures in follow-up. Of those without acute seizures, none had seizures in follow-up.

Figure 2

Kaplan-Meier curve illustrating the probability of seizure occurrence after discharge for (A) all 59 neonates with follow-up data for review, and (B) the 35 neonates who experienced acute symptomatic seizures. Hashmarks indicated individuals censored. The 95% confidence interval is shown in color.