EEG Pattern in Generalized Convulsive Status Epilepticus (GCSE) Predicts Response to Treatment
Abstract number :
3.172
Submission category :
Year :
2000
Submission ID :
1772
Source :
www.aesnet.org
Presentation date :
12/2/2000 12:00:00 AM
Published date :
Dec 1, 2000, 06:00 AM
Authors :
David M Treiman, Nancy Y Walton, Joseph F Collins, Dva Status Epilepticus Cooperative Study Group, UMDNJ-Robert Wood Johnson Medical Sch, New Brunswick, NJ; West Los Angeles VAMC, Los Angeles, CA; DVA Cooperative Study Program Coordinating Ctr, Perry Poi
RATIONALE: Treiman et al. (Epilepsy Res 5:49-60, 1990) described a predictable sequence of EEG patterns during GCSE: I. discrete electrographic szs, II. waxing and waning ictal discharges, III. continuous ictal discharges, IV. continuous discharges punctuated by flat periods, V. periodic epileptiform discharges. The study presented here was done to determine if the EEG pattern at time of initial treatment of GCSE predicts success. METHODS: Data from a comparative trial (NEJM 339:792-798, 1998) of lorazepam (0.1 mg/kg, phenobarbital 15 mg/kg, phenytoin 18 mg/kg and phenytoin followed by diazepam 0.15 mg/kg) in the initial treatment of GCSE were utilized. The EEG pattern was determined for the 266 of 518 patients for whom EEG data were available at or prior to initiation of the treatment protocol, and classified according to the patterns described above. Treatment success was defined as cessation of all behavioral and electrical evidence of seizure activity within 20 minutes after the start of drug infusion, with no further seizure activity during the subsequent 40 minutes. RESULTS: Overt GCSE and subtle GCSE differed significantly (?2 = 83.7, p < 0.001) in the distribution of EEG patterns, with earlier patterns more common in overt GCSE and later patterns more common in subtle GCSE. In general, the earlier the pattern the better the success of the first study treatment (I. 76.9%, II. 31.0%, III. 23.3%, IV. 7.4%, V.6.3%; ?2 = 99.6, p < 0.001), success of one or two treatments (I. 85.1%, II. 48.3%, III. 31.5%, IV. 11.1%, V. 31.1%; ?2 = 90.2, p < 0.001) or ability to stop GCSE with any treatments within the 12 hour protocol (I. 95.5%, II. 85.7%, III. 71.0%, IV. 45.3%, V. 46.9%; ?2 = 49.5, p < 0.001). Similar treatment responses were observed when separate analyses were done on overt and subtle GCSE groups and on each of the drug treatment groups. CONCLUSIONS: The EEG pattern at the time of initiation of treatment in GCSE predicts probability of success of treatment. The earlier the EEG stage the more likely treatment will be successful; the later the EEG pattern the harder GCSE is to treat. The EEG pattern appears to be a marker of the underlying pathophysiologic state of the brain in GCSE.