Electroencephalographic Seizures in Emergency Department Patients After Treatment for Convulsive Status Epilepticus

Abstract

It is unknown how often and how early EEG is obtained in patients presenting with status epilepticus. The Established Status Epilepticus Treatment Trial enrolled patients with benzodiazepinerefractory seizures and randomized participants to fosphenytoin, levetiracetam, or valproate. The use of early EEG, including frequency of electrographic seizures, was determined in Established Status Epilepticus Treatment Trial participants.Methods: Secondary analysis of 475 enrollments at 58 hospitals to determine the frequency of EEG performed within 24 hours of presentation. The EEG type, the prevalence of electrographic seizures, and characteristics associated with obtaining early EEG were recorded. Chi-square and Wilcoxon rank-sum tests were calculated as appropriate for univariate and bivariate comparisons. Odds ratios are reported with 95% confidence intervals.Results: A total of 278 of 475 patients (58%) in the Established Status Epilepticus Treatment Trial cohort underwent EEG within 24 hours (median time to EEG: 5 hours [interquartile range: 3-10]). Electrographic seizure prevalence was 14% (95% confidence interval, 10%-19%; 39/278) in the entire cohort and 13% (95% confidence interval, 7%-21%) in the subgroup of patients meeting the primary outcome of the Established Status Epilepticus Treatment Trial (clinical treatment success within 60 minutes of randomization). Among subjects diagnosed with electrographic seizures (39), 15 (38%; 95% confidence interval, 25%-54%) had no clinical correlate on the video EEG recording.Conclusions: Electrographic seizures may occur in patients who stop seizing clinically after treatment of convulsive status epilepticus. Clinical correlates might not be present during electrographic seizures. These findings support early initiation of EEG recordings in patients suffering from convulsive status epilepticus, including those with clinical evidence of treatment success.

Comparison of induction agents for rapid sequence intubation in refractory status epilepticus: A single-center retrospective analysis

“…We found that it took a median of 4.2 h for initiation of EEG monitoring which may have decreased our sensitivity to detect ESz and ESE following intubation thus masking any differences in time to seizure occurrence, though the time to initiate EEG monitoring and incidence of ESE we detected was comparable to the literature. [37] This variability in timing of EEG monitoring limited our ability to assess incidence of periodic patterns on EEG, a potentially important factor in patients with primary brain injury. [38] Importantly, we were limited to utilization of clinical EEG reports, rather than raw EEG data, to assess our outcome of interest.…”

Utility and rationale for continuous EEG monitoring: a primer for the general intensivist

“…Additionally, a secondary analysis from the established status epilepticus treatment trial (ESETT) found that only 58% (278/475) of a subgroup of patients had an EEG performed within the first 24 h post-seizure onset, with a median time to EEG recording of 5 h (IQR: 3–10 h) [ 32 ]. Emergent EEGs are infrequently performed in the ED, especially during nighttime and on weekends, primarily due to logistical challenges associated with the application of EEG in the ED, such as limited space, availability of technologists, and a lack of expertise in acute EEG interpretation, compounded by generally low clinical suspicion [ 33 ].…”

Management of status epilepticus: a narrative review

“…ABC, airway, breathing and circulation; IV, intravenous; AED, anti-epileptic drug; CBC, complete blood count; CMP, complete metabolic panel; CT, computed tomography; EEG, electroencephalogram; MRI, magnetic resonance imaging; KD, ketogenic diet; rTMS, repetitive transcranial magnetic stimulation; and VNS, vagal nerve stimulator. out' into subtle semiology [5,6], eventually becoming nonconvulsive following initiation of firstor second-line AEDs.…”

“…Non‐convulsive status epilepticus can present with or without coma, with protean manifestations in a broad range of contexts. This includes a subset of patients presenting with convulsive status epilepticus that transforms or ‘burns out’ into subtle semiology [5, 6], eventually becoming non‐convulsive following initiation of first‐ or second‐line AEDs. Non‐convulsive status epilepticus, even if prolonged, may not require intensive care or anaesthetic management.…”