Seizure clustering during presurgical electroencephalographic monitoring in children

Background Presurgical evaluation with antiseizure medication tapering in patients with refractory epilepsy places them at risk for seizure clustering or prolonged seizures. We looked at the occurrence of seizure clustering (3 or more seizures within 24 h) and prolonged seizures and the factors that influence seizure clustering and affect length of stay (LOS) in pediatric patients during presurgical monitoring. Methods We retrospectively reviewed the medical records of all consecutive admissions to the epilepsy monitoring unit (EMU) and included patients undergoing noninvasive presurgical evaluation. Data were extracted regarding demographics, seizure history, details of the EMU admission including occurrence of seizure clusters, prolonged seizures, status epilepticus, treatment, and LOS. Results Sixty-nine patients met our inclusion criteria. Seizure clustering during monitoring was observed in 33 patients (48%). Prolonged seizures lasting >5 min was observed in 14 (20%) patients including 2 with status epilepticus (3%). Seizure clusters necessitated rescue treatment in around 30%. History of seizure clustering at home was the only factor associated with the occurrence of seizure clustering during the EMU stay (p < 0.0001). The LOS did not differ significantly between patients who had seizure clustering during monitoring versus those who did not (p = 0.369). Conclusions Seizure clustering was common in children undergoing presurgical monitoring and seen especially in those with a history of seizure clustering at home. Occurrence of seizure clustering did not prolong the LOS but necessitated the use of rescue medications in about a third of the patients with seizure clusters due to multiple seizures.