Treatment of seizure emergencies: Convulsive and non-convulsive status epilepticus

Neurofilament light (NfL) as biomarker in serum and CSF in status epilepticus

OBJECTIVE

We explored the potential of neurofilament light chain (NfL) in serum and cerebrospinal fluid as a biomarker for neurodestruction in status epilepticus.

METHODS

In a retrospective analysis, we measured NfL in serum and cerebrospinal fluid samples of patients with status epilepticus using a highly sensitive single-molecule array technique (Simoa). Status epilepticus was diagnosed according to ILAE criteria. Additionally, we employed an alternative classification with more emphasis on the course of status epilepticus. We used data from three large control groups to compare NfL in status epilepticus versus neurologically healthy controls.

RESULTS

We included 28 patients (mean age: 69.4 years, SD: 15 years) with a median status duration of 44 h (IQR: 80 h). Twenty-one patients (75%) suffered from convulsive status epilepticus and seven (25%) from non-convulsive status epilepticus. Six patients died (21%). Cerebrospinal fluid and serum NfL concentrations showed a high correlation (r = 0.73, p < 0.001, Pearson). The main determinant of NfL concentration was the status duration. NfL concentrations did not differ between convulsive status epilepticus and convulsive status epilepticus classified according to the ILAE or to the alternative classification without and with adjusting for status duration and time between status onset and sampling. We found no association of NfL concentration with death, treatment refractoriness, or prognostic scores.

CONCLUSION

The results suggest that neurodestruction in status epilepticus measured by NfL is mainly determined by status duration, not status type nor therapy refractoriness. Therefore, our results suggest that regarding neurodestruction convulsive and non-convulsive status epilepticus are both neurological emergencies of comparable urgency.

Sex-related Differences in Glial Fibrillary Acidic Protein-positive GABA Regulate Neuropathology Following Pilocarpine-induced Status Epilepticus

Status epilepticus (SE) is a life-threatening neurological disorder that causes neuronal death and glial activation. Studies have explained the clinical side effects and lack of effectiveness of neurological disorder treatments based on sex-related differences in brain structure and function. However, the sex-specific outcomes of seizure disorders and the underlying mechanisms remain unknown. We compared SE-induced behavioral and pathophysiological changes in male and female mice. The time taken to reach stage 6 seizure following pilocarpine injection was shorter in male mice than in female mice, and the prevalence of SE was higher in male mice than in female mice. Fluoro-Jade B staining revealed more extensive SE-induced hippocampal neuronal death in male mice than in female mice. Glial cells were more activated in male mice than in female mice. In contrast, astrocyte-derived γ-aminobutyric acid (GABA)-immunostaining was less expressed in male mice than in female mice. Moreover, the mRNA levels of inflammatory cytokines released from activated glial cells were higher in male mice than in female mice. Notably, the mRNA level of astrocytic γ-aminobutyric acid transporter (GAT-3) involved in extracellular GABA uptake was lower in female mice than in male mice, while the mRNA levels of glutamate/aspartate transporter (GLAST (EAAT1)) and glutamate transporter (GLT-1 (EAAT2)) involved in extracellular glutamate uptake were higher in female mice. Our findings suggest that male mice are more vulnerable to SE than female mice, resulting in more extensive neuronal cell death and glial activation in male mice, partly due to increased GAT-3 expression that subsequently leads to reduced glial fibrillary acidic protein (GFAP)-positive GABA content assessed with anti-GABA antibodies.

Triphasic Waves: Historical Overview of an Unresolved Mystery

SUMMARY

Triphasic waves are a fascinating and mysterious EEG feature. We now have to accept that, at times, epileptiform discharges may have a blunted "triphasic morphology," and that there may be great difficulty in distinguishing between these often similar forms. The aim of this review was to describe the evolution in our understanding of triphasic waves that has occurred regarding the pathophysiology of triphasic waves, their most frequent causes, and the diagnostic difficulties involved in interpretation and differentiation from nonconvulsive status epilepticus.

Comparison of cubosomes and hexosomes for the delivery of phenytoin to the brain

The ability to formulate cubosomes and hexosomes with a single lipid by changing only the colloidal stabiliser presents a unique opportunity to directly compare the biological performance of these uniquely structured nanoparticles. This was explored here via the encapsulation and brain delivery of a model anti-seizure drug, phenytoin, in selachyl alcohol cubosomes and hexosomes. Nanoparticles were prepared with Pluronic® F127 or Tween 80® as the stabiliser and characterised. The internal nanostructure of nanoparticles shifted from hexosomes when using Pluronic® F127 as the stabiliser to cubosomes when using Tween 80® and was conserved following loading of phenytoin, with high encapsulation efficiencies (>97%) in both particle type. Cytotoxicity towards brain endothelial cells using the hCMEC/D3 line was comparable regardless of stabiliser type. Finally, in vivo brain delivery of phenytoin encapsulated in cubosomes and hexosomes after intravenous administration to rats was studied over a period of 60 min, showing cubosomes to be superior to hexosomes, both in terms of brain concentrations and brain to plasma ratio. While the role of stabiliser and/or internal nanostructure remains to be conclusively determined, this study is the first in vivo comparison of cubosomes and hexosomes for the delivery of a therapeutic drug molecule across the BBB and into the brain.

Treatment of established status epilepticus in the elderly - a study protocol for a prospective multicenter double-blind comparative effectiveness trial (ToSEE)

BACKGROUND

Status epilepticus (SE) is a common neurological emergency condition that especially affects the elderly and old population. Older people with SE frequently have non-convulsive SE (NCSE) and are also at special risk of suffering a poor outcome. The application of benzodiazepines fails to control SE in about one third of the cases. For benzodiazepine refractory SE (BRSE) in elderly, there is little evidence that would justify the choice of one of the commonly used antiepileptic drugs. The present study aims to generate evidence for the treatment of BRSE in this age group.

METHODS

We will conduct a prospective, randomized, double-blind comparative effectiveness study in more than twenty hospitals in Germany over a four-year period. Four hundred and seventy-seven elderly patients (≥ 65 years old) diagnosed with BRSE will be allocated by 1:1 randomization to receive either levetiracetam or valproate. All types of SE will be considered. For the diagnosis NCSE a verification by EEG is required. Levetiracetam or valproate will be administered in one single infusion. The primary endpoint is the stable cessation of ictal activity 15 min after the start of infusion persisting for the following 45 min of observation. EEG recording is maintained over the whole observation period, clinical examinations are conducted in predefined intervals. In case of treatment success patients and study staff remain blinded until 60 min after the start of the infusion. Adverse events will be recorded until the end of the study. EEG data will be reviewed by two external independent experts. To obtain data about the further treatment of SE, intrahospital complications and the functional outcome in the short term the study participants will be observed until the day of discharge or day 30 whichever is earliest.

DISCUSSION

ToSEE is the first study which shall deliver evidence for the SE-therapy in the elderly and old population in a controlled prospective comparator study. By design it also shall collect information about therapy regimes and outcome aspects of this disease.

TRIAL REGISTRATION

The trial has been registered at the German Clinical Trials Register on 3 July, 2020 ( DRKS00022308 ,  https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00022308 ).

Intranasal midazolam as first-line inhospital treatment for status epilepticus: a pharmaco-EEG cohort study

Objective

We sought to evaluate the efficacy and tolerability of intranasal midazolam (in‐MDZ) as first‐line inhospital therapy in patients with status epilepticus (SE) during continuous EEG recording.

Methods

Data on medical history, etiology and semiology of SE, anticonvulsive medication usage, efficacy and safety of in‐MDZ were retrospectively reviewed between 2015 and 2018. Time to end of SE regarding the administration of in‐MDZ and ß‐band effects were analyzed on EEG and with frequency analysis.

Results

In total, 42 patients (mean age: 52.7 ± 22.7 years; 23 females) were treated with a median dose of 5 mg of in‐MDZ (range: 2.5–15 mg, mean: 6.4 mg, SD: 2.6) for SE. The majority of the patients suffered from nonconvulsive SE (n = 24; 55.8%). In total, 24 (57.1%) patients were responders, as SE stopped following the administration of in‐MDZ without any other drugs being given. On average, SE ceased on EEG at 05:05 (minutes:seconds) after the application of in‐MDZ (median: 04:56; range: 00:29–14:53; SD:03:13). Frequency analysis showed an increased ß‐band on EEG after the application of in‐MDZ at 04:07 on average (median: 03:50; range: 02:20–05:40; SD: 01:09). Adverse events were recorded in six patients (14.3%), with nasal irritations present in five (11.9%) and prolonged sedation occurring in one (2.6%) patient.

Conclusions

This pharmaco‐EEG–based study showed that in‐MDZ is effective and well‐tolerated for the acute treatment of SE. EEG and clinical effects of in‐MDZ administration occurred within 04:07 and 5:05 on average. Intranasal midazolam appears to be an easily applicable and rapidly effective alternative to buccal or intramuscular application as first‐line treatment if an intravenous route is not available.

Use of Emergency Medication in Adult Patients with Epilepsy: A Multicentre Cohort Study from Germany

BACKGROUND

Emergency treatment with benzodiazepines is indicated in prolonged seizures, seizure clusters and status epilepticus.

OBJECTIVE

The aim of this study was to evaluate the use of emergency medication in adult patients with epilepsy.

PATIENTS AND METHODS

All adult epilepsy patients attending the epilepsy outpatient clinics of the university hospitals in Frankfurt and Marburg in 2015 were asked to participate in this questionnaire-based, retrospective survey.

RESULTS

A total of 481 patients with a mean age of 43.4 years (range 18-94 years, 54% female) participated in the study. Among them, 134 patients (27.9%) reported on the prescription of an emergency medication during the last year. Patients receiving emergency medication were younger and exhibited a lower age at epilepsy onset, a higher seizure frequency and a higher number of regularly taken antiepileptic drugs. The most frequently taken emergency drugs were oral lorazepam tablets (65.7%; n = 88 out of 134), followed by buccal midazolam (23.9%, n = 32) and rectal diazepam (17.9%, n = 24). The most common indications for administering the emergency medication were seizures continuing for several minutes (35.1%, n = 47), but almost the same number of patients (33.6%, n = 45) stated that the rescue medication was given during or after every seizure. Regarding adverse events, sedation was named as a major (18.7%, n = 25) or moderate (29.1%; n = 39) problem by a substantial number of patients. Difficulties in administration were reported by 17 (13%) patients. Two-thirds assessed the efficacy of their emergency medication as good (50.7%, n = 68) or as very good (15.7%, n = 21). For multivariate logistic regression analysis, aspects such as young age at onset, active epilepsy, structural etiology, presence of generalised tonic-clonic seizures, past medical history of status epilepticus and living with another person independently predicted prescription of emergency medication.

CONCLUSIONS

In most cases, unsuitable benzodiazepines with slow absorption due to oral administration were prescribed, or buccal midazolam solution was used off-label in adults. Furthermore, inappropriate use of emergency medication at every seizure was reported by a substantial number of participating patients.

Interictal Epileptiform Activity in the Foramen Ovale Electrodes of a Frontotemporal Dementia Patient

Frontotemporal dementia (FTD) is a frequent cause of cognitive decline. While epilepsy is an important comorbidity of Alzheimer’s disease, we lack studies on its presence in FTD. We report on an FTD patient with transient, short-term changes of behavior and cognitive performance suggesting non-convulsive epilepsy. Video-EEG recording with foramen ovale (FO) electrodes revealed mesio-temporal epileptiform potentials, undetectable by scalp leads. We also found beta spindles in the FO electrodes, not described in the literature. We conclude that video-EEG monitoring with FO electrodes might usefully complement the assessment of dementia-associated epilepsy opening new perspectives in dementia-research.

Pathophysiology of status epilepticus

Status epilepticus (SE) is the maximal expression of epilepsy with a high morbidity and mortality. It occurs due to the failure of mechanisms that terminate seizures. Both human and animal data indicate that the longer a seizure lasts, the less likely it is to stop. Recent evidence suggests that there is a critical transition from an ictal to a post-ictal state, associated with a transition from a spatio-temporally desynchronized state to a highly synchronized state, respectively. As SE continues, it becomes progressively resistant to drugs, in particular benzodiazepines due partly to NMDA receptor-dependent internalization of GABA(A) receptors. Moreover, excessive calcium entry into neurons through excessive NMDA receptor activation results in activation of nitric oxide synthase, calpains, and NADPH oxidase. The latter enzyme plays a critical part in the generation of seizure-dependent reactive oxygen species. Calcium also accumulates in mitochondria resulting in mitochondrial failure (decreased ATP production), and opening of the mitochondrial permeability transition pore. Together these changes result in status epilepticus-dependent neuronal death via several pathways. Multiple downstream mechanisms including inflammation, break down of the blood-brain barrier, and changes in gene expression can contribute to later pathological processes including chronic epilepsy and cognitive decline.

Synthesis and Pharmacological Evaluation of New 3,4-Dihydroisoquinolin Derivatives Containing Heterocycle as Potential Anticonvulsant Agents

Two novel series of 3,4-dihydroisoquinolin with heterocycle derivatives (4a–t and 9a–e) were synthesized and evaluated for their anticonvulsant activity using maximal electroshock (MES) test and pentylenetetrazole (PTZ)-induced seizure test. All compounds were characterized by IR, ¹H-NMR, ¹³C-NMR, and mass spectral data. Among them, 9-(exyloxy)-5,6-dihydro-[1,2,4]triazolo[3,4-a]isoquinolin-3(2H)-one (9a) showed significant anticonvulsant activity in MES tests with an ED₅₀ value of 63.31 mg/kg and it showed wide margins of safety with protective index (PI > 7.9). It showed much higher anticonvulsant activity than that of valproate. It also demonstrated potent activity against PTZ-induced seizures. A docking study of compound 9a in the benzodiazepine (BZD)-binding site of γ-aminobutyric acid_A (GABA_A) receptor confirmed possible binding of compound 9a with the BZD receptors.

Managing Status Epilepticus in the Older Adult

The aim of this systematic review was to describe particularities in epidemiology, outcome, and management modalities in the older adult population with status epilepticus. There is a higher incidence of status epilepticus in the older adult population, and it commonly has a nonconvulsive presentation. Diagnosis in this population may be difficult and requires an unrestricted use of EEG. Short and long term associated-mortality are high, and age over 60 years is an independent factor associated with poor outcome. Stroke (acute or remote symptomatic), miscellaneous metabolic causes, dementia, infections hypoxemia, and brain injury are among the main causes of status epilepticus occurrence in this age category. The use of anticonvulsive agents can be problematic as well. Thus, it is important to take into account the specific aspects related to the pharmacokinetic and pharmacodynamic changes in older critically-ill adults. Beyond these precautions, the management may be identical to that of the younger adult, including prompt initiation of symptomatic and anticonvulsant therapies, and a broad and thorough etiological investigation. Such management strategies may improve the vital and functional prognosis of these patients, while maintaining a high overall quality of care.

Ictal and interictal EEG patterns in patients with nonconvulsive and subtle convulsive status epilepticus

BACKGROUND

Electroencephalography findings in nonconvulsive or subtle convulsive status epilepticus (NCSE and SCSE, respectively) can be heterogenous. We aimed to study the different patterns on EEG in our cohort of patients.

OBJECTIVE

Our objective was to study ictal and interictal EEG patterns in patients with NCSE and SCSE.

METHODS

From January 2012 to December 2013, EEGs recorded from patients admitted for altered mental status suspected of having NCSE or SCSE were reviewed retrospectively. Electroencephalography status was defined as having (a) continuous ictal discharges lasting >5 min or (b) >2 discrete bursts of ictal discharges, each lasting <5 min, without returning to previous background rhythm in between these bursts.

RESULTS

Among 1698 EEGs recorded for at least 30 min from hospitalized patients, 55 (3.23%) satisfied the criteria of EEG SE. The ictal onset was regional in 37 (67.2%) EEGs, multiregional independent in 8 (14.5%), and generalized in 10 (18.4%). The EEG seizure duration was >5 min in 24 (43.6%) EEGs, between 1 and 5 min in 14 (25.4%), and less than 1 min in 17 (30.8%). Twenty (36.3%) EEGs showed one continuous prolonged seizure episode of >5-minute duration, 15 (27.2%) had 10 or less discrete episodes, 20 (36.3%) had more than 10 episodes, and 11 (20%) had 2 or more ictal patterns. Thirty (54.5%) EEGs had onset ictal frequency of >8 Hz whereas the rest had <8-Hz ictal frequency. In the interictal segment, 29 patients had continuous generalized slow waves, while 12 had intermittent generalized slow waves. Eleven patients had continuous slow waves lateralized to one hemisphere, and these were ipsilateral to the ictal focus in 10 but contralateral in 1. Other interictal waves seen were PLEDS (6), sharp waves (3), suppression (5), and triphasic waves (1). The background alpha rhythm was absent in 36 patients and slow in 14, and normal background alpha was seen in the interictal period in 5 patients.

CONCLUSION

The ictal and interictal EEG patterns in NCSE and SCSE can be varied. Further study to look for etiologic and clinical correlates of each pattern could add to its clinical value. This article is part of a Special Issue entitled "Status Epilepticus".

A Review of Phenytoin Monotherapy in Adults With Nonrefractory Status Epilepticus

Objective: To review the literature evaluating the efficacy of phenytoin monotherapy in adults with nonrefractory status epilepticus. Data Sources: Articles were selected through a search of MEDLINE/PubMed (1966 to August 2014), using the terms phenytoin and status epilepticus. A further review of reference citations was performed to identify other relevant articles. Study Selection and Data Extraction: English-language case reports and clinical studies were reviewed. Publications evaluating the efficacy of phenytoin monotherapy primarily in adults with nonrefractory status epilepticus were included in the review. Two case studies and 5 clinical studies met the criteria. Data Synthesis: The ultimate goal for status epilepticus treatment is seizure cessation. Phenytoin, a venerable and oft-utilized antiepileptic, has been employed in first-line and second-line regimens for status epilepticus. Unfortunately, despite decades of use, data on the efficacy of phenytoin monotherapy in these nonrefractory cases have been limited. The available studies are quite heterogeneous in design, with variable underlying etiologies of status epilepticus, doses of study drugs, and comparators. Additionally, most are underpowered. When administered as second-line therapy, phenytoin monotherapy is comparable to valproic acid in abating status epilepticus. As first-line therapy, phenytoin monotherapy was inferior to lorazepam but not diazepam when used in combination with phenytoin or phenobarbital. Two other studies comparing phenytoin with valproic acid as first-line therapy had conflicting results. Conclusions: In adults with nonrefractory status epilepticus, phenytoin monotherapy is a viable option for second-line therapy. The data do not consistently support phenytoin monotherapy's use as first-line treatment. More robust and adequately powered clinical studies are needed to assess whether these results remain consistent and extend to more long-term efficacy measures, such as morbidity and mortality.

The relative effectiveness of five antiepileptic drugs in treatment of benzodiazepine-resistant convulsive status epilepticus: a meta-analysis of published studies

PURPOSE

Systematic evaluation of published evidence-base of the efficacy of five antiepileptic drugs - lacosamide, levetiracetam, valproate, phenytoin and phenobarbital - in convulsive benzodiazepine-resistant status epilepticus.

METHODS

Data sources included electronic databases, personal communication, and back tracing of references in pertinent studies. These were prospective and retrospective human studies presenting original data for participants with convulsive benzodiazepine-resistant status epilepticus. Interventions were intravenous lacosamide, levetiracetam, phenobarbital, phenytoin and valproate. Outcome measured is clinically detectable cessation of seizure activity. Level-of-evidence was assessed according to Oxford Centre of Evidence-Based Medicine and The Cochrane Collaboration's Tool for Assessment of Risk. Twenty seven studies (798 cases of convulsive status epilepticus) were identified and 22 included in a meta-analysis. Random-effects analysis of dichotomous outcome of a single group estimate (proportion), with inverse variance weighting, was implemented. Several sources of clinical and methodological heterogeneity were identified.

RESULTS

Efficacy of levetiracetam was 68.5% (95% CI: 56.2-78.7%), phenobarbital 73.6% (95% CI: 58.3-84.8%), phenytoin 50.2% (95% CI: 34.2-66.1%) and valproate 75.7% (95% CI: 63.7-84.8%). Lacosamide studies were excluded from the meta-analysis due to insufficient data.

CONCLUSION

Valproate, levetiracetam and phenobarbital can all be used as first line therapy in benzodiazepine-resistant status epilepticus. The evidence does not support the first-line use of phenytoin. There is not enough evidence to support the routine use of lacosamide. Randomized controlled trials are urgently needed.

Intravenous lacosamide as treatment option in post-stroke non convulsive status epilepticus in the elderly: a proof-of-concept, observational study

PURPOSE

To evaluate the efficacy and safety of intravenously administered lacosamide (iv LCM) in post-stroke non convulsive status epilepticus (NCSE) in elderly patients.

METHODS

We enrolled 16 patients (7 M/9 F; 77 ± 7 years of age) with NCSE. iv LCM was used in all the patients as initial treatment (i.e. patients were directly started on LCM) at a loading dose of 400 mg over 30 min, followed by a mean maintenance dose of 400 mg per day. iv LCM was considered as effective in patients who experience no NCSE for 24 h following treatment, as evaluated by EEG recording and clinical observation.

RESULTS

LCM was effective in treating NCSE in eight of the sixteen patients in whom epileptic activity disappeared (7/8) or was significantly reduced (1/8) within 45-60 min after administration. None of these patients relapsed in the following 24 h. No adverse events were observed. A partial anterior circulation syndrome (PACS) was present in 10 patients while a total anterior circulation syndrome (TACS) in six.

CONCLUSIONS

This pilot study suggests that LCM exhibits safety and efficacy profiles which make it an optimal candidate as a first-choice drug against post-stroke NCSE in elderly patients. A prospective comparative trial is needed to confirm these preliminary data.

[Non-convulsive status epilepticus: temporary fad or reality in need of treatment?]

The term non-convulsive status epilepticus (NCSE) refers to a heterogeneous group of diseases with different etiology, prognosis and treatment. The different forms of NCSE comprise about 25-50% of all status epilepticus cases. The most frequent form encountered in clinical practice is complex-partial SE but the rarer conditions of absence status, aura status and subtle SE are also included under this category. A diagnosis of NCSE should be considered in all patients with otherwise unexplained changes in consciousness or behavior and this diagnosis demands rapid further diagnostic work up including clinical examination, a detailed clinical history from the patient or an accompanying person, cranial computed tomography (CCT) and an electroencephalogram (EEG). If signs of an infectious or inflammatory disorder are present, a spinal tap is indicated. The EEG is of high relevance although interpretation can be challenging in NCSE.Absence status is usually treated by benzodiazepines and if necessary a broad spectrum anticonvulsive drug (ACD) such as valproic acid (VPA) can be added. The treatment of complex-partial SE follows the same scheme as that of generalized tonic-clonic SE and an initial benzodiazepine (i.v. lorazepam or intramuscular midazolam) followed by a bolus of one of the ACDs available as i.v. solution (e.g. VPA, phenytoin, phenobarbitol or levetiracetam). The third treatment step is general anesthesia if NCSE fails to be controlled. The aggressiveness of the applied therapy depends on the severity of the NCSE and the general condition of the patient. The prognosis is determined by the subtype of NCSE and the underlying etiology.

The brain, seizures and epilepsy throughout life: understanding a moving target

The human brain is a tremendously complex and still enigmatic three-dimensional structure, composed of countless interconnected neurons and glia. The temporal evolution of the brain throughout life provides a fourth dimension, one that influences every element of the brain's function in health and disease. This temporal evolution contributes to the probability of seizure generation and to the type and the nature of these seizures. The age-specific properties of the brain also influence the consequences of seizures on neuronal structure and behavior. These, in turn, govern epileptic activity and cognitive and emotional functions, contributing to the diverse consequences of seizures and epilepsy throughout life.

Guidelines for the evaluation and management of status epilepticus

Status epilepticus (SE) treatment strategies vary substantially from one institution to another due to the lack of data to support one treatment over another. To provide guidance for the acute treatment of SE in critically ill patients, the Neurocritical Care Society organized a writing committee to evaluate the literature and develop an evidence-based and expert consensus practice guideline. Literature searches were conducted using PubMed and studies meeting the criteria established by the writing committee were evaluated. Recommendations were developed based on the literature using standardized assessment methods from the American Heart Association and Grading of Recommendations Assessment, Development, and Evaluation systems, as well as expert opinion when sufficient data were lacking.

A comparative electrographic analysis of the effect of sec-butyl-propylacetamide on pharmacoresistant status epilepticus

Better treatment of status epilepticus (SE), which typically becomes refractory after about 30 min, will require new pharmacotherapies. The effect of sec-butyl-propylacetamide (SPD), an amide derivative of valproic acid (VPA), on electrographic status epilepticus (ESE) was compared quantitatively to other standard-of-care compounds. Cortical electroencephalograms (EEGs) were recorded from rats during ESE induced with lithium-pilocarpine. Using a previously-published algorithm, the effects of SPD on ESE were compared quantitatively to other relevant compounds. To confirm benzodiazepine resistance, diazepam (DZP) was shown to suppress ESE when administered 15 min after the first motor seizure, but not after 30 min (100mg/kg). VPA (300 mg/kg) also lacked efficacy at 30 min. SPD (130 mg/kg) strongly suppressed ESE at 30 min, less after 45 min, and not at 60 min. At a higher dose (180 mg/kg), SPD profoundly suppressed ESE at 60 min, similar to propofol (100mg/kg) and pentobarbital (30 mg/kg). After 4-6h of SPD-induced suppression, EEG activity often overshot control levels at 7-12h. Valnoctamide (VCD, 180 mg/kg), an SPD homolog, was also efficacious at 30 min. SPD blocks pilocarpine-induced electrographic seizures when administered at 1h after the first motor seizure. SPD has a faster onset and greater efficacy than DZP and VPA, and is similar to propofol and pentobarbital. SPD and structurally similar compounds may be useful for the treatment of refractory ESE. Further development and use of automated analyses of ESE may facilitate drug discovery for refractory SE.

Problems and controversies in status epilepticus: a review and recommendations

Status epilepticus (SE) is a neurologic emergency that require immediate vigorous treatment in order to prevent serious morbidity or even death. Several investigators have suggested that the underlying etiology is the primary determinant of outcome. We believe that this may be true in aggressively treated SE, but not when the treatment is less than optimal. In this article, we will discuss the factors that have been implicated in affecting SE outcomes, and argue, on the basis of both human and experimental animal data, that aggressive treatment is necessary and appropriate for all presentations of SE in order to maximize the probability of a successful outcome even when the etiology suggests a poor prognosis.

Single-channel amplitude integrated EEG recording for the identification of epileptic seizures by nonexpert physicians in the adult acute care setting

OBJECTIVE

Although several studies have shown the potential of amplitude integrated electroencephalography (aEEG) in detecting neonatal seizures, no publications have evaluated the diagnostic use of aEEG for the detection of seizures in adult patients.

METHODS

In this prospective blinded observational study, bifrontal single-channel electroencephalography (EEG) recordings were performed with a portable EEG monitor (CSM M3 ICU, Danmeter-Goalwick Holdings Limited, Odense, Denmark) during the out-of-hospital care of emergency cases. Four intensive care unit (ICU) physicians received training in the interpretation of aEEG recordings. After the training they evaluated the stored aEEG traces for the presence of epileptic seizure activity during the recording time. The physicians were blinded to the clinical data of the patients. The results obtained were compared with the clinical diagnosis and the evaluation of the raw EEG signal. The level of interrater agreement was quantified using Fleiss' ĸ.

RESULTS

The aEEG traces from 10 patients with generalized epileptic seizures and 46 patients without seizures were analysed. Overall, the nonexpert ICU physicians failed to identify recordings obtained from patients with seizures reliably, when compared with clinical diagnosis and the single-channel EEG results (mean sensitivity 40%, range 40-60%; mean specificity 89%, range 87-93%). Agreement between observers was high for the cases with seizures ( ĸ = 0.80 ± 0.13). Patients who suffered status epilepticus during the recordings were difficult to identify by most raters.

CONCLUSION

Recording of aEEG without access to the raw EEG data is not a reliable diagnostic tool for the identification of epileptic seizures in the hands of nonexpert ICU physicians.

Neurologic emergencies in patients who have cancer: diagnosis and management

The nervous system can be significantly affected by cancer. Neurologic symptoms are present in 30% to 50% of oncologic patients presenting to the emergency department or in neurologic consultation at teaching hospitals. Evaluation and treatment require collaborative effort between specialties. The causes of neurologic emergencies in patients with cancer are mostly related to effects of cancer, toxicities of treatments, infections, and paraneoplastic syndromes. These complications cause significant morbidity and mortality and require prompt and accurate diagnostic and treatment measures. This article reviews the common neurologic emergencies affecting patients with cancer and discusses epidemiology, clinical presentation, diagnosis, and treatment modalities.

Nonconvulsive status epilepticus: a diagnostic and therapeutic challenge in the intensive care setting

Nonconvulsive status epilepticus (NCSE) comprises a group of syndromes that display a great diversity regarding response to anticonvulsants ranging from virtually self-limiting variants to entirely refractory forms. Therefore, treatment on intensive care units (ICUs) is required only for a selection of cases. The aetiology and clinical form of NCSE are strong predictors for the overall prognosis. Absence status epilepticus is commonly seen in patients with idiopathic generalized epilepsy and is rapidly terminated by low-dose of benzodiazepines. The management of complex partial status epilepticus is straightforward in patients with pre-existing epilepsy, but poses major problems if occurring in the context of acute brain lesions. Subtle status epilepticus represents the late stage of undertreated previous overt generalized convulsive status epilepticus and always requires aggressive ICU treatment. Within the intensive care setting, the diagnostic challenge may be seen in the difficulty in delineating nonepileptic conditions such as posthypoxic, metabolic or septic encephalopathies from NCSE. Although all important forms are considered, the focus of this review lies on clinical presentations and electroencephalogram features of comatose patients treated on ICUs and possible diagnostic pitfalls.

Outcome and prognosis of status epilepticus in children

The ultimate goal of treating status epilepticus is to provide the best opportunity for a good outcome. This review discusses the current literature on the outcome after status epilepticus in children, including the risk of recurrence, morbidity, and mortality. The outcome seems most dependent on etiology, with age and duration of status epilepticus also contributing. Convulsive status epilepticus has considerably more supporting literature, whereas the data on nonconvulsive status epilepticus are hindered by the lack of a standard definition and presumed under recognition. Future studies will need to address some of these methodological issues to provide the best information when discussing outcome with the family members of children with status epilepticus.

Levetiracetam in nonconvulsive status epilepticus in a child with Angelman syndrome

Children with Angelman syndrome have an increased risk of developing a nonconvulsive status epilepticus. Although the urgency to treat nonconvulsive status epilepticus depends on the underlying illness, most clinicians and authors agree that treatment should be focused to rapidly terminate this condition. Until now, the use of levetiracetam to treat nonconvulsive status epilepticus in children is based only on some case reports. Our case further supports this treatment regime for a subgroup of children with a special risk of nonconvulsive status epilepticus and developmental delay.

Status epilepticus

Status epilepticus (SE) in adults is a state of continuous seizures lasting more than 5 minutes, or rapidly recurrent seizures without regaining consciousness. The overall US and European estimated crude incidence rate of SE ranges from 6.8 to 41/100,000/yr. The etiologies of SE include primary central nervous system pathologies and systemic disorders. The two basic mechanisms involved in the genesis of SE are an excess of excitatory activity and a loss of normal inhibitory neurotransmission. Mortality associated with SE can be as high as 26% for the average adult. Early recognition and treatment are important for improving the chances for a good outcome. The first line of treatment is an intravenous benzodiazepine, with lorazepam being the current preferred agent. All patients with SE who remain with altered awareness 20 to 30 minutes after cessation of clinical seizures should undergo electroencephalographic studies, because up to 20% of patients without clinical evidence of seizures after initial treatment can have nonconvulsive SE.

Nonconvulsive status epilepticus

Nonconvulsive status epilepticus (NCSE) is a heterogeneous disorder with multiple subtypes. Although attempts have been made to define and classify this disorder, there is yet no universally accepted definition or classification that encompasses all subtypes or electroclinical scenarios. Developing such a classification scheme is becoming increasingly important, because NCSE is more common than previously thought, with a bimodal peak, in children and the elderly. Recent studies have also shown a high incidence of NCSE in the critically ill. Although strong epidemiological data are lacking, NCSE constitutes about 25-50% of all cases of status epilepticus. For the purposes of this review, we propose an etiological classification for NCSE including NCSE in metabolic disorders, NCSE in coma, NCSE in acute cerebral lesions, and NCSE in those with preexisting epilepsy with or without epileptic encephalopathy. NCSE is still underrecognized, yet potentially fatal if untreated. Diagnosis can be established using an electroencephalogram (EEG) in most cases, sometimes requiring continuous monitoring. However, in comatose patients, diagnosis can be difficult, and the EEG can show a variety of rhythmic or periodic patterns, some of which are of unclear significance. Although some subtypes of NCSE are easily treatable, such as absence status epilepticus, others do not respond well to treatment, and debate exists over how aggressively clinicians should treat NCSE. In particular, the appropriate treatment of NCSE in patients who are critically ill and/or comatose is not well established, and large-scale trials are needed. Overall, further work is needed to better define NCSE, to determine which EEG patterns represent NCSE, and to establish treatment paradigms for different subtypes of NCSE.

Epileptic fits and epilepsy in the elderly: general reflections, specific issues and therapeutic implications

Seizures and epilepsy are commonly encountered in the elderly. Diagnosis is not always straightforward as reliable history is often difficult to obtain and EEG findings can be non-specific. When to treat and how may be difficult choices as adequate studies in elderly are rather scarce. Treatment should be based on careful assessment and comparison of risk/benefit profiles of various anti-epileptic drugs (AEDs) in this specific elderly population. Since most AEDs are effective in terms of seizure control in the elderly, the choice of treatment is often determined by tolerability, pharmacokinetic profile and drug interactions of AEDs. As recently introduced AEDs have a better safety profile compared to older agents it seems logical to initiate treatment in the frail elderly patient with those more modern AEDs. In this review some distinctive clinical features of epilepsy in the elderly are discussed in three sections (general issues, special issues and selected treatment options with special reference to medicinal treatment).

Acute confusion or altered mental state: consider nonconvulsive status epilepticus

BACKGROUND

The diagnosis of nonconvulsive status epilepticus (NCSE) is particularly challenging in elderly patients. Confusion, personality change, dysphasia, subtle motor activity and nystagmus may be the only presenting signs.

OBJECTIVE

To review current knowledge about NCSE with special focus on older people.

METHODS

Systematic review of the current literature via Medline search.

CONCLUSION

Although prospective studies are still lacking, NCSE may be one of the most frequently missed diagnoses in patients presenting with altered mental status. Elderly patients are at particular risk of diagnostic errors because of the broad range of presentations of NCSE, significant comorbidities (especially cerebrovascular disease), limited awareness of this particular seizure emergency or difficulties with access to electroencephalography. Although diagnostic criteria and treatment remain controversial, the diagnosis of NCSE is important because it is potentially reversible.

New GABA-modulating 1,2,4-oxadiazole derivatives and their anticonvulsant activity

A series of 3- and 5-aryl-1,2,4-oxadiazole derivatives were prepared and tested for anticonvulsant activity in a variety of models. These 1,2,4-oxadiazoles exhibit considerable activity in both pentylenetetrazole (PTZ) and maximal electroshock seizure (MES) models. Compound 10 was protective in the PTZ model in rats with an oral ED(50) of 25.5mg/kg and in the MES model in rats with an oral ED(50) of 14.6mg/kg. Neurotoxicity (rotarod) was observed with an ED(50) of 335mg/kg. We found several oxadiazoles that acted as selective GABA potentiating compounds with no interaction to the benzodiazepine binding site.

Levetiracetam in nonconvulsive status epilepticus in childhood: a case report

The authors report the case of a child with cerebral palsy and refractory epilepsy who developed nonconvulsive status epilepticus without acute medical cause treated successfully with levetiracetam. In accordance with other studies whose authors hypothesized that aggressive treatment may worsen the prognosis in elderly patients with nonconvulsive status epilepticus, the present authors successfully used a more conservative approach to the treatment of nonconvulsive status epilepticus in their patient. This case suggests that levetiracetam is a useful option for the treatment of nonconvulsive status epilepticus in childhood, in accordance with some authors who have described the anticonvulsant effects of levetiracetam in experimental status epilepticus and in status epilepticus in adults and in children with continuous spike waves during slow sleep.

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

Non-convulsive status epilepticus (NCSE) is one of the great diagnostic and therapeutic challenges of modern neurology. Because the clinical features of this disorder may be very discrete and sometimes hard to differentiate from normal behaviour, NCSE is usually overlooked and consequently not treated properly. It is important to be familiar with the clinical subtypes such as absence, simple and complex partial, and subtle status epilepticus because each requires tailored management. In order to improve overall care of patients with NCSE, strict diagnostic criteria are needed that should be based on clinical alterations and ictal electroencephalographic changes. NCSE should be terminated rapidly to prevent patients from serious injuries, particularly if consciousness is impaired.

Palliative Care Consultation in the Process of Organ Donation after Cardiac Death

Palliative care consultation has been demonstrated to be useful in many situations in which expert symptom management, communication around sensitive issues, and family support may serve to enhance or improve care. The process of organ donation is an example of this concept, specifically the process of donation after cardiac death (DCD). DCD allows patients with severe, irreversible brain injuries that do not meet standard criteria for brain death to donate organs when death is declared by cardiopulmonary criteria. The DCD method of donation has been deemed an ethically appropriate means of organ donation and is supported by the organ procurement and medical communities, as well as the public. The palliative care (PC) team can make a significant contribution to the care of the patient and family in the organ donation process. In this paper we describe the controlled DCD process at one institution that utilizes the PC team to provide expert end-of-life care, including comprehensive medical management and family support. PC skills and principles applicable to the DCD process include communication, coordination of care, and skillful ventilator withdrawal. If death occurs within 90 minutes of withdrawal of life support, organs may be successfully recovered for transplantation. If the patient survives longer than 90 minutes, his or her care continues to be provided by the PC team. Palliative care can contribute to standardizing quality end-of-life care practices in the DCD process and provide education for involved personnel. Further experience, research and national discussions will be helpful in refining these practices, to make this difficult and challenging experience as gentle and supportive as possible for the courageous families who participate in this process.

Treatment of convulsive status epilepticus

Status epilepticus (SE) is a medical and neurological emergency requiring prompt and aggressive treatment, particularly for elderly individuals in whom comorbid conditions may increase the severity of consequences in SE. Generalized convulsive status epilepticus (GCSE) is the most common and life-threatening type of SE. It may be overt or subtle in its presentation. Most cases are overt, but as the duration of GCSE increases, its presentation may become more subtle. Progressive electroencephalographic changes also occur during GCSE. A predictable sequence of five electroencephalographic patterns has been identified: (1) discrete seizures with interictal slowing, (2) merging seizures with waxing and waning ictal discharges, (3) continuous ictal sharp or spike-wave discharges, (4) continuous ictal discharges with episodes of generalized flattening, and (5) periodic epileptiform discharges superimposed on a relatively flat background. Several factors affect the prognosis of GCSE, including etiology, age, seizure type, gender, and duration. GCSE may lead to systemic complications and neuronal damage and is often fatal if untreated or inadequately treated. Treatment of GCSE should begin with basic life support measures and monitoring. Ideally, pharmacological treatment should be easy to administer and fast acting. Analysis of data on elderly patients with overt GCSE from a Veterans Affairs cooperative study revealed that success rates of first-line treatment were 71.4% for phenobarbital, 63.0% for lorazepam, 53.3% for diazepam followed by phenytoin, and 41.5% for phenytoin alone. In elderly patients with subtle GCSE, success rates for first-line treatment were 30.8% for phenobarbital, 14.3% for lorazepam, 11.8% for phenytoin, and 5.6% for diazepam followed by phenytoin. Because each drug has advantages and disadvantages, the choice of which agent to use as first-line treatment depends on individual patient characteristics.

[Clinical features, diagnosis, and treatment of dysphoric states and psychoses associated with epilepsy]

Although dysphoric states and psychoses represent clinically relevant psychiatric complications in patients with epilepsy, their symptomatologies are complex and therefore frequently underrecognized and undertreated in daily psychiatric routine. Detecting dysphoric states and psychoses secondary to the psychotropic effects of various antiepileptic drugs is often challenging, even for the most experienced psychiatrists. This article gives an overview of epidemiology, clinical features, diagnosis, and therapy of interictal, peri-ictal, and alternative dysphoric states and psychoses in patients with epilepsy. Further, potential drug interactions between antiepileptic and psychiatric medications are discussed.

Elders with epilepsy

Why is it important to learn about epilepsy in the elderly? The answers are many. As this article has highlighted, compared with younger individuals epilepsy is more common and the causes are more structural and symptomatic than in younger patients (particularly stroke). The clinical presentation is different in the elderly. The diagnosis is more difficult and often delayed. The most common seizures are simple partial and complex partial seizures, which are more often extratemporal in location. Confusion and memory problems are common presenting symptoms and postictal deficits often are prolonged. The prognosis for epilepsy in the elderly generally is favorable for seizure control, but if untreated, depression and quality of life suffer and seizures frequently recur. Seizures respond well at lower serum concentrations of antiepileptic drugs but these patients are also more sensitive (less tolerant) to side effects at lower doses than younger adults.