Abstracts

Rationale: Neonates who require extracorporeal membrane oxygenation (ECMO) for cardiorespiratory support are at an increased risk for acute symptomatic seizures, including neonates with congenital diaphragmatic hernia (CDH) who have a seizure incidence of 10-20%. As high seizure exposure is associated with worse neurodevelopmental outcomes, most clinicians treat neonatal seizures. However, formal guidelines for management of neonatal seizures in neonates with CDH and ECMO are lacking, and there is often significant variability between providers. We aimed to describe the management of seizures in neonates with CDH on ECMO at a single center.

Methods: We performed a retrospective review of prospectively collected data from a single center level IV NICU at the Children’s Hospital of Philadelphia. We included neonates with CDH on ECMO with electroencephalographic (EEG)-confirmed seizures between 2004-2019. Clinical and EEG data were collected from electronic medical records. Statistical analysis was performed using Stata with descriptive data presented as counts (%) and medians (interquartile range), and tests of comparison performed with Fisher’s exact test and Wilcoxon rank sum.

Results: Twenty-four of 106 (23%) neonates with CDH on ECMO experienced EEG-confirmed seizures and all (100%) were treated acutely with an antiseizure medication (ASM). All patients received phenobarbital as the initial medication at a median dose of 20mg/kg (19.1, 20). The median time between seizure identification and treatment was 2 hours (1.2, 3.8), and time to treatment did not vary by seizure burden (p=1.00). No adverse effects were reported with any of the ASMs administered. Phenobarbital monotherapy resulted in seizure cessation in 17 patients (71%). The remaining 7 patients (29%) received a second ASM, most often levetiracetam (6/7, 86%). More ASMs were administered to patients with status epilepticus (67% vs 10% receiving 3+ ASMs, p=0.005), and patients with status epilepticus were less likely to respond to treatment (0% vs 86%, p=0.01). Maintenance ASM was started in 23 patients (96%), but only 1 patient of 6 patients (17%) who survived the hospitalization was discharged on an ASM.

Conclusions: Phenobarbital was the most common ASM administered to neonates with CDH on ECMO experiencing seizures, and it was both well-tolerated and efficacious. While maintenance ASM were often administered, most survivors had ASM discontinued during the hospitalization. Patients with lower seizure burden were more likely to respond to ASM and required a smaller number of ASM, suggesting that earlier recognition and treatment of seizures could result in improved response with less medication exposure.

Funding: Please list any funding that was received in support of this abstract.: None.