Effective withdrawal of antiepileptic drugs in premonitoring admission to capture seizures during limited video‐EEG monitoring

Abstract

SummaryObjectiveWithdrawal of antiepileptic drugs (AEDs) is commonly applied to capture seizures in video‐EEG (vEEG) monitoring for patients with infrequent but intractable seizures. Because of the half‐life of AEDs, AED withdrawal during only vEEG tends to be inadequate to provoke seizures within the vEEG admission. We hypothesize that prewithdrawal of long‐half‐life AEDs in premonitoring admission (PMA) is safe and effective to capture seizures in the limited time of vEEG. We determined the effect of half‐life on the interval between AED withdrawal and seizure occurrence.MethodsWe collected 87 patients with three criteria: (1) seizure occurrence ≤3 per month; (2) AEDs ≥2; (3) AED withdrawal during their admission, among 126 consecutive patients who underwent vEEG in the Department of Neurosurgery, Hiroshima University Hospital between 2011 and 2014. We divided patients into two groups on the basis of half‐life of AED: Group A (23 patients) with phenobarbital (PB) and/or zonisamide (ZNS); Group B (64 patients) with other AEDs. In Group A, PB and ZNS were withdrawn during 4‐day PMA before vEEG started. Further AED withdrawal was performed during vEEG, depending on the seizure occurrence.ResultsThe number of AEDs on admission was significantly higher in Group A (2–6, 3.5 ± 0.9; range, mean ±SD) than in Group B (2–5, 2.8 ± 0.8) (p < 0.01). All 23 Group A patients and 13 (20%) Group B patients underwent AED withdrawal during PMA. Seizures occurred during PMA in two patients in both Group A (9%) and Group B (15%). The first seizure occurred significantly longer after the start of withdrawal in Group A (6.1 ± 2.0 days) than in Group B (2.8 ± 1.3 days) (p < 0.01). Seizures were equally captured between both groups: 96% in Group A and 92% in Group B during vEEG.SignificanceFor epilepsy patients who are treated with PB and/or ZNS, we recommend the planning of AED withdrawal during PMA before the start of vEEG to succeed in capturing seizures during the limited time of vEEG monitoring.

Relationship between Delta Rhythm, Seizure Occurrence and Allopregnanolone Hippocampal Levels in Epileptic Rats Exposed to the Rebound Effect

“…In clinical practice, AED discontinuation is required during a long EEG monitoring period to enhance the rate of successful diagnostics [ 7 ] and to precisely defining the epileptogenic zone [ 26 , 27 ]. However, an important concern is that few guidelines on AED withdrawal during a lengthy stay in EEG monitoring have been published [ 8 ], so the outcome might be doubly uncertain. Indeed, this procedure may trigger secondarily generalized tonic-clonic SRSs, SRS clustering, and status epilepticus in patients [ 9 , 28 ].…”

“…In epileptic patients who are candidates for surgical treatment, the rapid discontinuation of AEDs is required during the presurgical evaluation of video-electroencephalogram (v-EEG) monitoring [ 5 , 6 , 7 , 8 ]. However, this procedure can trigger the so-called “rebound effect”, which is characterized by transient seizure generalization or even prolonged increase in frequency of partial seizures [ 5 ].…”

Impact of withdrawal of antiepileptic medication on the duration of focal onset seizures

“…Thus, it is well accepted to partially or totally withdraw AEDs in the EMU to precipitate seizures, more so as it is unlikely to influence the localizing significance of the recorded seizures [1][2][3][4][5]. AED withdrawal is typically associated with an increase in seizure frequency and generalization rate [6][7][8][9]. The increase in seizure frequency and generalized seizures correlates with the taper rate and is more pronounced for carbamazepine and oxcarbazepine than for other AEDs like phenytoin, valproate or lamotrigine [6,7,10].…”

Clinical Application of Pharmacokinetics to Appraise Adherence to Levetiracetam in Portuguese Epileptic Patients

“…Patients are admitted to the hospital on a Monday, and their discharge occurs on the following Saturday or Sunday. In the morning of the admission day, patients do not take the prescribed antiseizure drugs because drug discontinuation is required to precipitate seizures for VEEG monitoring [ 30 , 31 , 32 , 33 , 34 ]. Following the reintroduction of antiseizure drugs (usually on Wednesday or Thursday), patients remain in the hospital for 2 to 3 additional days, to ensure that drug plasma concentrations reach therapeutic levels.…”