Status epilepticus: Management and prognosis

Abstract

Status epilepticus is one of the most common neurological emergencies. Its incidence in adults is 36.1/100.000 per year (Leitinger et al. Epilepsia 2019). Less than half of the patients had previous seizures. Mortality varies according to the type of SE: case fatality is lower in awake patients (8.2%) compared with patients with impaired consciousness (33%) (Leitinger et al. Epilepsia 2019). SE is defined as “a condition resulting either from the failure of the mechanisms responsible for seizure termination or from the initiation of mechanisms, which lead to abnormally, prolonged seizures (after time point t1). It is a condition, which can have long-term consequences (after time point t2), including neuronal death, neuronal injury, and alteration of neuronal networks, depending on the type and duration of seizures”. (Trinka et al. Epilepsia 2015). It is a highly dynamic condition, which requires early diagnosis and treatment to prevent long term consequences. About 60% of patients in Convulsive SE (CSE) will be controlled by first line treatment (Trinka et al. Expert Opin Pharmacother. 2016). Recent studies suggest, that there is significant undertreatment in the early stages of status: Up to 80% receive not the recommended dose of Benzodiazepines (Kellinghaus et al. Ann Neurol 2019). If treatment is delayed, or the patient does not respond to adequate Benzodiazepines the stage of refractory SE (RSE) is reached, where anaesthetic treatments are necessary. The causes of SE must be identified by all means [8]. Common causes should be established in the first hours and treated appropriately, if causes cannot be identified the term NORSE (New Onset RSE) is used. At this stage extensive investigations are necessary to identify (and treat) the cause. In nearly 50% of cases, the probable cause of NORSE can eventually be determined. (Gaspard et al. Neurology 2015). The most commonly identified etiologies include autoimmune (19%) and paraneoplastic encephalitis (18%) or infection-related (8%). Once the patient is under general anaesthesia, major complications, such as pneumonia, immunosuppression, acidosis, metabolic derangements, cardiac suppression, gastric paresis, and others have to be managed appropriately. Overall RSE and super-refractory SE (SRSE), which does not respond to > 24h of general anaesthesia, is rare (7.2 and 1.2 / 100.000 / year), but mortality is highest in this group (Leitinger et al. Epilepsia 2019). One of the main diagnostic challenges at this stage, which is still unsolved, is the distinction between coma due to SE and coma with SE like EEG patterns (Trinka and Bauer Epilepsia 2009). This presentation will give an up to date overview on management and prognosis of SE.[1Bauer G. Trinka E. Nonconvulsive status epilepticus and coma.Epilepsia. 2010; 51: 177-190Google Scholar, 2Gaspard N. Foreman B.P. Alvarez V. Cabrera Kang C. Probasco J.C. Jongeling A.C. Meyers E. Espinera A. Haas K.F. Schmitt S.E. Gerard E.E. Gofton T. Kaplan P.W. Lee J.W. Legros B. Szaflarski J.P. Westover B.M. LaRoche S.M. Hirsch L.J. Critical Care EEG Monitoring Research Consortium (CCEMRC). New-onset refractory status epilepticus: Etiology, clinical features, and outcome.Neurology. 2015; 85: 1604-1613Google Scholar, 3Hirsch L.J. Gaspard N. van Baalen A. Nabbout R. Demeret S. Loddenkemper T. Navarro V. Specchio N. Lagae L. Rossetti A.O. Hocker S. Gofton T.E. Abend N.S. Gilmore E.J. Hahn C. Khosravani H. Rosenow F. Trinka E. Proposed consensus definitions for new-onset refractory status epilepticus (NORSE), febrile infection-related epilepsy syndrome (FIRES), and related conditions.Epilepsia. 2018; 59: 739-744Google Scholar, 4Kellinghaus C. Rossetti A.O. Trinka E. Lang N. May T.W. Unterberger I. Rüegg S. Sutter R. Strzelczyk A. Tilz C. Uzelac Z. Rosenow F. Factors predicting cessation of status epilepticus in clinical practice: Data from a prospective observational registry (SENSE).Ann Neurol. 2019; 85: 421-432Google Scholar, 5Leitinger M. Trinka E. Giovannini G. Zimmermann G. Florea C. Rohracher A. Kalss G. Neuray C. Kreidenhuber R. Höfler J. Kuchukhidze G. Granbichler C. Dobesberger J. Novak H.F. Pilz G. Meletti S. Siebert U. Epidemiology of status epilepticus in adults: A population-based study on incidence, causes, and outcomes.Epilepsia. 2019; 60: 53-62Google Scholar, 6Trinka E. Cock H. Hesdorffer D. Rossetti A.O. Scheffer I.E. Shinnar S. Shorvon S. Lowenstein D.H. A definition and classification of status epilepticus--Report of the ILAE Task Force on Classification of Status Epilepticus.Epilepsia. 2015; 56: 1515-1523Google Scholar, 7Trinka E. Höfler J. Leitinger M. Rohracher A. Kalss G. Brigo F. Pharmacologic treatment of status epilepticus.Expert Opin Pharmacother. 2016; 17: 513-534Google Scholar, 8Trinka E. Höfler J. Zerbs A. Causes of status epilepticus.Epilepsia. 2012; 53: 127-138Google Scholar]