Abstracts

Rationale:Seizures are a common presentation of intracranial hemorrhage due to arteriovenous malformations (AVMs) in the pediatric intensive care unit (PICU). Despite this, there are limited studies assessing the incidence of electrographic seizures (ES), EEG findings, and subsequent epilepsy in this population.

Methods: This study is a retrospective review of all patients admitted to the PICU at Children's National Hospital with intracranial hemorrhage secondary to AVM from January 2011- April 2022. Patients were excluded if they presented with a non-ruptured AVM or if initial management was at an outside hospital. Variables collected included age, sex, presenting symptom of the AVM, initial GCS score and PCPC score. Imaging features consisted of the location of hemorrhage, identified as supratentorial or infratentorial, and the presence of intraventricular hemorrhage (IVH) or associated infarction. Other imaging variables collected included the presence of hydrocephalus, herniation, and volume of hemorrhage. EEG features included the EEG background, presence or absence of background asymmetry, (ES) and epileptiform discharges. The EEG background within the first 24 hours, was categorized into a slow/disorganized, discontinuous, burst suppression , and an attenuated background. Seizures were described acute (within the first 7 days of indentificaiton of the AVM), and remote ( greater than 30 days since AVM detection). Acute and remote seizures were clinical, or EEG confirmed. Outcome measures included mortality, discharge PCPC score, and the development of epilepsy. Fishers exact test was used to assess for associations with the development of epilepsy. 

Results: Forty-two patients met inclusion criteria with a mean age of 11.1 years (standard deviation (SD) 4.09) and 52% (22/42) were male. Fifteen percent (6/42) presented with a clinical seizure, with the majority (67% (28/42)) presenting with acute headache. The mean initial GCS score was 9.13 (SD 4.8) and 21% (9/42) required hemicraniectomy. EEG was performed in 62% (26/42) of patients; amongst those patients, a slow/disorganized background was the most common (81% (21/26), 50% (13/26) had asymmetry and one patient had ES. The patient with ES had both generalized and focal seizures. We identified acute seizures in 17% (7/42), remote seizures in 14% (6/41) and 10% (4/42) went on to develop epilepsy. Patients were diagnosed with epilepsy 1.5 years (SD 0.74) after AVM identification.  Acute seizures were not associated with the development of epilepsy (14% vs. 10 %, p=0.5) while remote seizure were associated with the development of epilepsy (67% vs. 10%, p< 0.0001).