Prognosis in nonconvulsive status epilepticus

Nonconvulsive status epilepticus (NCSE) is a type of status epilepticus (SE) lacking a predominant motor manifestation. The annual prevalence of NCSE is estimated to reach 10 to 20 cases in every 100,000 people. While almost half of all SE cases are nonconvulsive, there are several different types of NCSE: 1) epileptic absence SE, 2) epileptic focal seizure SE with consciousness disturbance (complex partial SE), 3) de novo NCSE of late onset, 4) NCSE due to acute brain injury or prolonged consciousness disturbance after convulsive SE. An electroencephalography (EEG) evaluation is necessary to diagnose NCSE. However, continuous EEG (cEEG) monitoring over at least 24 hours is preferable to detect NCSE, as cognitive disturbances due to this condition may fluctuate over time. In addition, neuroimaging techniques, such as MRI with arterial spin labeled sequences or single photon emission computed tomography (SPECT) can demonstrate hyperperfused areas in cases of focal onset. Thus, patients presenting with alternative cognitive disturbance with or without mild confusion should be evaluated using cEEG monitoring or blood flow imaging so as not to overlook treatable NCSE.

Nonconvulsive status epilepticus in adults: Electroclinical differences between proper and comatose forms

DOOR syndrome concomitant with non-convulsive status epilepticus and hyperintense cerebellar cortex on T2-weighted imaging

A 27-year-old man had a 5-year history of a peculiar state characterized by clouded consciousness provoked by ingestion of alcohol. The episode was identified electroclinically as nonconvulsive status epilepticus and was activated by ingestion of alcohol. Single-photon emission computed tomography (SPECT) examination during the nonconvulsive status epilepticus showed increased regional cerebral perfusion in the right frontal region. This finding, along with the EEG expressions, supports a cortical origin of the nonconvulsive status epilepticus and a diagnosis of complex partial status epilepticus (CPSE). To our knowledge, this is the first report of a documented case of CPSE during intoxication provoked by alcohol ingestion and also of a SPECT examination during CPSE.

Background: In the elderly, nonconvulsive status epilepticus (NCSE) is frequent, however there are still gaps in knowledge about the types of presentation, ictal EEG patterns and prognosis. It is questioned whether the prognosis is related to the etiological factor. Objective: To evaluate the prognosis and clinical-EEG variables in older adults with NCSE according to remote or primary acute etiology. Methods: Clinical-EEG data and the occurrence of death at 30 days in 90 elderly patients diagnosed with NCSE of structural etiology (primary acute or remote) treated at the clinical neurology service of the PUC-Campinas Hospital were evaluated and compared. Results: The mean age was 72.6±8.3 years and 57(63.3%) cases were female, 53(58.9%) cases had acute etiology and 37(41.1%) had remote etiology. The NCSE type was - NCSE-coma in 41(45.6%) cases and NCSE-without coma in 49(54.4%) cases. No significant difference was observed in gender and age according to the type of etiology. There was no difference in the ictal EEG pattern (Salzburg Criterion - A1, A2, A3, A4) according to acute or remote etiology. Death within 30 days occurred in 32(35.6%) cases, with no difference according to etiology. Previous history of seizures/epilepsy occurred more and significantly in older adults with NCSE of remote etiology (Fisher’s exact test, 6(11.3%) vs 17(45.9%), p< 0.000). There was a difference in the type of NCSE according to the etiology, with a higher occurrence of NCSE-coma in cases with acute etiology (chi-square test; 30 vs 11, p=0.012). Conclusion: In the elderly with NCSE, there were differences in the clinical variables according to the acute/remote etiology. Previous history of seizures/epilepsy occurred more frequently in the NCSE of remote etiology, and the clinical presentation of coma was more frequent in the elderly with NCSE of acute etiology. Mortality in this sample was high, with no difference according to acute/remote etiology in elderly patients with NCSE. FAPESP 2023/01226-4.

Nonconvulsive Status Epilepticus in the Elderly: A Case Series and a Review of the Literature

Electroencephalographic patterns in unresponsive pediatric patients

Therapeutic coma is advocated in guidelines for management of refractory status epilepticus; this is, however, based on weak evidence. We here address the specific impact of therapeutic coma on status epilepticus outcome. Retrospective assessment of a prospectively collected cohort. Academic hospital. Consecutive adults with incident status epilepticus lasting greater than or equal to 30 minutes, admitted between 2006 and 2013. We recorded prospectively demographics, clinical status epilepticus features, treatment, and outcome at discharge and retrospectively medical comorbidities, hospital stay, and infectious complications. Associations between potential predictors and clinical outcome were analyzed using multinomial logistic regressions. Of 467 patients with incident status epilepticus, 238 returned to baseline (51.1%), 162 had new disability (34.6%), and 67 died (14.3%); 50 subjects (10.7%) were managed with therapeutic coma. Therapeutic coma was associated with poorer outcome in the whole cohort (relative risk ratio for new disability, 6.86; 95% CI, 2.84-16.56; for mortality, 9.10; 95% CI, 3.17-26.16); the effect was more important in patients with complex partial compared with generalized convulsive or nonconvulsive status epilepticus in coma. Prevalence of infections was higher (odds ratio, 3.81; 95% CI, 1.66-8.75), and median hospital stay in patients discharged alive was longer (16 d [range, 2-240 d] vs 9 d [range, 1-57 d]; p < 0.001) in subjects managed with therapeutic coma. This study provides class III evidence that therapeutic coma is associated with poorer outcome after status epilepticus; furthermore, it portends higher infection rates and longer hospitalizations. These data suggest caution in the straightforward use of this approach, especially in patients with complex partial status epilepticus.

S176. A Mean field model to study the triphasic waves in acute hepatic encephalopathy

Introduction: Status epilepticus is one of the most common neurological emergency, with high morbidity and mortality and an often poor functional prognosis in survivors. We carried out the present study, to describe the intra-hospital clinical course and to identify the risk factors for intra-hospital death of patients hospitalized for status epilepticus in Ouagadougou, Burkina Faso. Patients and methods: it was a prospective, cross-sectional, multi-center hospital, descriptive and analytical study, which took place from January 1, 2015 to December 31, 2019, involving patients consecutively hospitalized in the university hospitals of Ouagadougou, for status epilepticus. Sociodemographic characteristics, clinical data on admission, biological assessment on admission, EEG characteristics, brain scan and / or brain MRI results ; etiological diagnosis of status epilepticus and intra hospital evolutionary data of the patients, have been analyzed. Univariate analysis between the general characteristics of patients and the intra-hospital mortality, was performed in order to identify the risk factors for the intrahospital mortality. Results: The mean age of the patients was 36.6 years with an M / F sex ratio of 1.4 ; 66 patients (72.5%) had no clinical history of epilepsy, while 25 patients (27.5%) were already known to have epilepsy. The generalized tonic-clonic SE immediately (50.5%) and the focal secondarily generalized convulsive status epilepticus (29.7%) were the most common seizure types. The average duration of an SE episode was 18 hours. status epilepticus were subdivided into status epilepticus symptomatic of acute brain conditions with 61 cases (67%), dominated by central nervous system infections and acute strokes, and status epilepticus of non-acute or sequelae etiologies with 30 cases (33%), dominated by the sequelae of head trauma. Intra-hospital complications were dominated by prolonged post-critical mental confusion, 45 cases (49.4%) and aspiration pneumonia, 30 cases (33%). In-hospital mortality was 12.1% (11 patients). At the end of hospitalization, 49 patients (53.9%) still had moderate to severe disabilities. In univariate analysis, comatose non convulsive status epilepticus (p = 0.003), and altered consciousness on admission (p = 0.026), were the risk factors for in-hospital mortality. Conclusion: Prognosis of status epilepticus in Burkina Faso remains unfavorable with early mortality in more than one in 10 patients and poor functional outcome in more than half of the patients. Altered consciousness on admission and non-convulsive comatose status epilepticus were risk factors for early mortality. The fight against infectious diseases, the prevention of vascular risk factors, the promotion of helmet wearing in cyclists and motorcyclists, early admission of patients sufferinf of status epilepticus, and adequate and standardized management of status epilepticus, will help reduce the frequency and severity of this disease in our African regions.

Absence status epilepticus (ASE) is a type of nonconvulsive status epilepticus, in which varying grade of consciousness impairment lasting more than 15 minutes and are accompanied by constant generalized spike-wave complexes with a frequency of 2.5-4 Hz on the electroencephalogram (EEG). ASE can be observed in various epileptic syndromes, usually detected in children. In some cases, ASE manifests in adulthood as a late complication of idiopathic generalized epilepsy or status for the first time (de novo), without history of epilepsy. A review of reported cases of ASE manifestation in adulthood is presented and two of our own clinical observations of ASE that occurred in adult patients who did not have a previously established diagnosis of epilepsy are discussed. Quite clear clinical and EEG syndromic delineation of ASE in adults and the elderly, high effectivenefe of therapy and good outcome of the disease allow distinguishing recurrent ASE as a separate epileptic syndrome, in contrast to nonconvulsive status epilepticus in other neurological diseases.

The diagnosis of nonconvulsive status epilepticus (NCSE) relies largely on electroencephalography (EEG) findings. The lack of a unified EEG terminology, and of evidence-based EEG criteria, leads to varying criteria for and ability to diagnose NCSE. We propose a unified terminology and classification system for NCSE, using, as a template, the Standardised Computer-based Organised Reporting of EEG (SCORE). This approach integrates the terminology recently proposed for the rhythmic and periodic patterns in critically ill patients, the electroclinical classification of NCSE (type of NCSE) and the context for the pathologic conditions and age-related epilepsy syndromes. We propose flexible EEG criteria that employ the SCORE system to assemble a database for determining evidence-based EEG criteria for NCSE.

BackgroundContinuous electroencephalogram (CEEG) monitoring is increasingly being used for brain monitoring in neurocritical care setting. This is because of the proven effectiveness of CEEG in diagnosing nonconvulsive status epilepticus (NCSE) as a cause of unexplained consciousness disorder. CEEG has been demonstrated to be effective in determining the response to, and outcome of, NCSE treatment.Main bodyIn this review article, the authors described the indication and methods of CEEG and diagnosis based on EEG pattern. As a condition characterized by unexplained consciousness disorder, NCSE is frequently encountered in the neurocritical care setting and is only accompanied by an altered EEG change without any clinically apparent manifestation, such as convulsion. Thus, it is considered a form of status epilepticus manifesting mainly with consciousness disorder. This is a diagnostic challenge but should not be overlooked as NCSE is a curable condition. However, CEEG is required for the correct diagnosis of NCSE, which is difficult to perform in daily clinical practice. There also are several challenges regarding urgent EEG monitoring in the intensive care unit setting, including system-related problems, such as the preparation of mobile EEG devices and collodion-applied electrodes; human resource-related problems, such as staffing of EEG technicians and physicians who can respond flexibly to unscheduled needs; and EEG-specific difficulties in interpretation/diagnosis. These issues preclude the wide spread of CEEG in daily practice.ConclusionRecently, importance of CEEG was well accepted; however, no definitive diagnostic criteria exist for identifying EEG patterns suggestive of NCSE, especially the ambiguous significance of periodic discharges (PDs) further complicates the diagnosis of NCSE. Thus, analyzing the change in EEG patterns over time is important for the correct diagnosis of NCSE. Further studies are needed to collect sufficient CEEG data and assess the outcome of patients who have undergone therapeutic interventions.

Non-convulsive status epilepticus in adults: clinical forms and treatment

ObjectiveIn Western settings, non‐convulsive status epilepticus (NCSE) and non‐convulsive seizures (NCSz) are associated with high mortality. In comatose patients, interictal epileptiform discharges (IEDs) identified on routine electroencephalogram (EEG) are predictive of NCSE/NCS. Little is known regarding the prevalence, causes, or outcomes of NCSE/NCSz in sub‐Saharan Africa (SSA). We sought to investigate the prevalence of IEDs and NCSE/NCSz at a single teaching institution in SSA.MethodsFrom October 3, 2017, to May 21, 2018, adult inpatients on the internal medicine service at Zambia's University Teaching Hospital (UTH) with a Glasgow Coma Score (GCS) of ≤10 were identified, excluding patients with mechanical ventilation or open head wounds. Signed consent by a proxy was required for enrollment and 30‐minute EEG. Chart abstractions provided coma duration, presence/absence of clinical seizures during/prior to admission, history of epilepsy, and presumed coma etiology. A structured neurological examination was completed. Patients were followed to discharge or death. Risk factors for IEDs were evaluated.ResultsOf 392 eligible patients, 250 had EEGs. EEGs were not completed on eligible patients due to death (74), improved GCS (37), transfer within UTH (25), or lack of proxy (6). NCSE occurred in 22 of 250 (8.8%), NCSz in 3 of 250 (1.2%), and IEDs in 46 of 250 (18.4%) patients. Of the 250, 197 (78.8%) died. No specific risk factors for IEDs were identified.SignificanceIf the association between IEDs and NCSE among monitored populations in developed settings holds true for SSA, a projected 17%‐21% of comatose African adults have NCSE. No clinical characteristics identified those at risk.