Abstracts

Rationale: The aim of a patient admission to an epilepsy monitoring unit (EMU) includes event diagnosis, medication management, and seizure characterization and localization. The goal of provoking seizures without status epilepticus (SE) is typically achieved with sleep deprivation and antiepileptic drug (AED) withdrawal. However, a standardized AED wean protocol is rarely followed in the EMU. We studied the influence of AED weaning patterns on time to seizure occurrence and frequency of status epilepticus in a pediatric EMU.Methods: 882 consecutive admissions to the EMU at Childrens of Alabama were prospectively studied from Jan 2012 to May 30, 2013. Admissions for invasive monitoring (27) and those with no AED withdrawal (780) were excluded. AED withdrawal was initiated by the decision of the attending physician. Results: 65 children underwent 75 admissions associated with AED withdrawal during this period. Mean age at admission was 10.8 years (range = 0.8 - 20). Indication for admission included seizure characterization or localization for pre-surgical evaluation. Four children underwent 2 admissions while 3 underwent 3 admissions. The average number of AEDs was 2.2, including 1(22), 2(23), 3(20), and 4(10). AED weaning followed 2 general patterns; the most common pattern included AED discontinuation 1-2 days before admission or AED discontinuation on day of admission (61), while the second pattern involved decrease in AED dosage and/or subsequent discontinuation after day 1 of admission (14). The average admission included monitoring for 3.8 nights (3 -10). During 14 of 75 admissions (19%), no seizures were recorded despite discontinuation of AEDs on or before admission. Seizures were recorded during 61 admissions (81%); 46 of 61 admissions involved AED discontinuation on or before the day of admission versus admissions with AED discontinuation or decrease after the first day of admission (15 of 61), 2 = 4.3, p = .03. The average time to seizure was 1.3 days (1-4). Clinical status epilepticus occurred in 5 of 75 admissions (7%). Four patients had seizures lasting >10 minutes while 1 patient had markedly increased seizure frequency with a seizure cluster lasting 15 minutes. One of 5 patients was intubated and observed overnight in the pediatric intensive care unit. Four of 5 patients had AED withdrawal before or on day of admission while 1 of 5 underwent medication wean after day 1 of admission. One of 5 patients had previous history of SE. All 5 patients had developmental delay and intractable epilepsy. Conclusions: Our prospective study shows that AED withdrawal (1-2 days before or on admission) safely achieves the goal of recording seizures within 1 to 2 days after admission. Despite a high risk pediatric population, the frequency of provoked status epilepticus with AED withdrawal is low and prior history of status epilepticus may not be contributing factor. Furthermore, our results suggest that a standardized protocol for AED withdrawal prior or on day of admission may be safe and effective in provoking seizures in the EMU.