Abstracts

Treiman and Walton have described the existence of five EEG ictal patterns that occur in sequence in generalized convulsive status epilepticus (GCSE). These patterns include: I discrete seizures (DSP), II: merging seizures (MSP), III, continuous ictal discharges (CIDP), IV Continuous ictal discharges with flat periods (CIDFPP), V: periodic epileptiform discharges on a flat background (PEDP). The latter three patterns have been associated with longer duration of status prior to treatment and an increased risk of refractory GCSE. The sequence of these EEG patterns in simple (SPSE) and complex partial status epilepticus (CPSE) is yet to be investigated., Twelve patients, 10 in CPSE and two in SPSE underwent continuous V-EEG monitoring from the time of diagnosis to the resolution of seizure activity at the Rush Epilepsy Center from 7/1/05 to 5/31/06. Eight were women; the mean age was 47.6 years (range 20 to 68). Eight had a prior history of epilepsy.
Video-EEG recordings were reviewed in their entirety by the two investigators independently who identified the initial ictal pattern at the start of the monitoring, their evolution and the last ictal pattern prior to resolution of the seizure activity. The duration of seizure activity prior to admission was estimated on the bases of the available history obtained from family members. We investigated the association between the ictal patterns sequence and (i)the duration to remission of ictal activity, (ii) the development of refractory SE, defined as the need to use a coma protocol with midazolam, propofol or pentobarbital., In 9 of the 12, patients the estimated pre-treatment duration of SE was longer than 24 hours; 6 presented with CPSE and 3 with SPSE. The ictal recordings of the 3 patients with SPSE consisted of DSP. Among the 6 patients in CPSE a MSP was found in 1, a CIDP/CIDFPP in 4 and a PEDP with intermixed recurrent elctrographic seizures in one. In none of these patients did the initially recorded ictal pattern change throughout the duration of therapy until the achievement of seizure-freedom. Among the six patients with CPSE, three developed refractory SE; two had a CIDP/CIDFPP and 1 a PEDP. One of the patients with CIDP/CIDFPP who was placed on midazolam and then propofol coma died of complications of pneumonia.
The estimated duration of status in the other 3 patients was less than 6 hours: 1 had DSP,1 had MSP and 1 had CIDP; the patient with CIDP went on to evolve to PLEDs with intermixed electrographic seizures. Seizure activity remitted with standard AEDs in all three patients., These data suggest that the ictal patterns described in GTCSE are also identified in CPSE and appear to be associated with pre-treatment duration of seizure activity and response to AED therapy. The EEG patterns in CPSE do not appear to evolve once pharmacotherapy has been initiated.,