Abstracts

Rationale: Patients often aquire intractable seizures despite trying multiple standard anticonvulsants. Many may be patients where epilepsy surgery is being considered or perhaps become labeled mixed seizure disorders or Lennox-Gastaut Syndrome. These patients sometimes have focal sources of their condition and may, because of their intractable clinical condition become difficult to control or characterize by EEG patterns in the sense they have become electrographically in a state of interictal continuous or semicontinuous spike or spike wave activity. Prior use of high dose valium has been described for cases of Landau-Kleffner Syndrome with continuous spike-wave in sleep (CSWS)using 1mg/kg diazepam orally or rectally. This was therefore tried in other intractable states of clincal epilespy with semicontinuous interictal activty. Methods: 16 patients with intractable encephalopathic epilepsy had multifocal or observed semicontinuous or continuous interictal spike-wave activity and were offered a trial of trying high dose oral or rectal diazepam as a single dose followed by a taper over several weeks. Patients were given an inital dose of 1mg/kg diazepam followed by weekly tapering of a 0.5mg/kg daily dose, usually in the evening.The dose was reduced by 0.1mg/kg/day doses weekly until off the medication. Seizure frequency and EEG follow-up was perforemd at 4 weeks after initial treatment. All patients had their doses given in the pediatric intensive care unit with monitoring continuously for heart rate and pulse oximetry. There were 10 males and 6 females, ages 20 months to 14 years of age. Results: 13/16 cases responded dramatically with improved spike-wave activity, often with normalization of awake background activity and greatly imrpoved localization of what had appeared to be generalzied or multifocal abnormalities in seven cases. Continuous spike-wave in sleep was resolved in 4 cases. Clinical seizure control appeared improved at follow-up in all 13 cases that improved.The 3 cases that failed to improve on EEG had significant diffuse cortical congenital malformation in 2 cases, and diffuse hypoxic damage in a third. There were no complications to respiration or heart rhythms, nor any significant clinical side effects other than transient ataxia and minimal lethergy. Most patients seemed more aware after their dosing. Conclusions: High dose valium of 1mg/kg as a single initial dose can in many intractable epilepsy cases with significantly abnormal EEG alter the clinical course of treatment when given aggressively with continuous video EEG monitoring and follow-up tapering dose over 6 weeks. This has improved clinical seizure control and also made 4 prior cases thought to be multifocal appear focal in onset and become potential epilepsy surgery cases in the future. More study using high dose valium trials in intractable epilepsy may be useful as a method to alter intractability and perhaps define potential candidates for epilepsy surgery.