Systemic effects of generalized convulsive status epilepticus

Super-refractory status epilepticus in a woman with Aeromonas caviae meningitis: a rare case report and review of the literature

Currently, there is a lack of knowledge regarding Aeromonas caviae meningitis. We report the first case of super-refractory status epilepticus (SRSE) in a woman with Aeromonas caviae meningitis. The case report demonstrates that this condition can lead to severe SRSE. Effective treatment for epilepsy is crucial for improving the prognosis for similar patients. According to Gomes et al.'s consensus protocol for SRSE, using a combination of up to one anesthetic drug and three non-anesthetic anti-epileptic drugs may be helpful and important in managing SRSE that is caused by Aeromonas caviae meningitis.

[S2k guidelines: status epilepticus in adulthood : Guidelines of the German Society for Neurology]

This S2k guideline on diagnosis and treatment of status epilepticus (SE) in adults is based on the last published version from 2021. New definitions and evidence were included in the guideline and the clinical pathway. A seizures lasting longer than 5 minutes (or ≥ 2 seizures over more than 5 mins without intermittend recovery to the preictal neurological state. Initial diagnosis should include a cCT or, if possible, an MRI. The EEG is highly relevant for diagnosis and treatment-monitoring of non-convulsive SE and for the exclusion or diagnosis of psychogenic non-epileptic seizures. As the increasing evidence supports the relevance of inflammatory comorbidities (e.g. pneumonia) related clinical chemistry should be obtained and repeated over the course of a SE treatment, and antibiotic therapy initiated if indicated.Treatment is applied on four levels: 1. Initial SE: An adequate dose of benzodiazepine is given i.v., i.m., or i.n.; 2. Benzodiazepine-refractory SE: I.v. drugs of 1st choice are levetiracetam or valproate; 3. Refractory SE (RSE) or 4. Super-refractory SE (SRSE): I.v. propofol or midazolam alone or in combination or thiopental in anaesthetic doses are given. In focal non-convulsive RSE the induction of a therapeutic coma depends on the circumstances and is not mandatory. In SRSE the ketogenic diet should be given. I.v. ketamine or inhalative isoflorane can be considered. In selected cased electroconvulsive therapy or, if a resectable epileptogenic zone can be defined epilepsy surgery can be applied. I.v. allopregnanolone or systemic hypothermia should not be used.

Association of systemic secondary brain insults and outcome in patients with convulsive status epilepticus: A post hoc study of a randomized controlled trial

OBJECTIVE

To evaluate the association between systemic factors (mean arterial blood pressure, arterial partial pressures of carbon dioxide and oxygen, body temperature, natremia, and glycemia) on day 1 and neurologic outcomes 90 days after convulsive status epilepticus.

METHODS

This was a post hoc analysis of the Evaluation of Therapeutic Hypothermia in Convulsive Status Epilepticus in Adults in Intensive Care (HYBERNATUS) multicenter open-label controlled trial, which randomized 270 critically ill patients with convulsive status epilepticus requiring mechanical ventilation to therapeutic hypothermia (32°C-34°C for 24 hours) plus standard care or standard care alone between March 2011 and January 2015. The primary endpoint was a Glasgow Outcome Scale score of 5, defining a favorable outcome, 90 days after convulsive status epilepticus.

RESULTS

The 172 men and 93 women had a median age of 57 years (45-68 years). Among them, 130 (49%) had a history of epilepsy, and 59 (29%) had a primary brain insult. Convulsive status epilepticus was refractory in 86 (32%) patients, and total seizure duration was 67 minutes (35-120 minutes). The 90-day outcome was unfavorable in 126 (48%) patients. In multivariate analysis, none of the systemic secondary brain insults were associated with outcome; achieving an unfavorable outcome was associated with age >65 years (odds ratio [OR] 2.17, 95% confidence interval [CI] 1.20-3.85; p = 0.01), refractory convulsive status epilepticus (OR 2.00, 95% CI 1.04-3.85; p = 0.04), primary brain insult (OR 2.00, 95% CI 1.02-4.00; p = 0.047), and no bystander-witnessed seizure onset (OR 2.49, 95% CI 1.05-5.59; p = 0.04).

CONCLUSIONS

In our population, systemic secondary brain insults were not associated with outcome in critically ill patients with convulsive status epilepticus.

CLINICALTRIALSGOV IDENTIFIER

NCT01359332.

The Role of Secondary Brain Insults in Status Epilepticus: A Systematic Review

(1) Background: Little is known about the impact of pathophysiological mechanisms that underlie the enhancement of excitotoxicity and the neuronal consequences of status epilepticus (SE), as well as the clinical consequences of secondary brain insults (SBI) in patients with SE on outcome; (2) Methods: Electronic searches were conducted in May 2020 using Medline via PubMed, Embase, and Google Scholar (#CRD42019139092). Experimental studies of animals or randomized, observational, controlled trials of patients with SE in indexed journals were included. There were no language or date restrictions for the published literature included in this review. Information was extracted on study design, sample size, SBI characteristics, and primary and secondary outcomes, including the timing of evaluation; (3) Results: Among the 2209 articles responding to our inclusion criteria, 56 were included in this systematic review. There are numerous experimental data reporting the deleterious effects associated with each of the SBI in animals exposed to SE. In humans, only the effect of target temperature management in hypothermia (32-34 °C) has been explored. (4) Conclusions: There is little experimental evidence that favors the control of secondary brain insult after SE. Further studies are required to assess the neuroprotective interest of secondary brain insult control after SE in humans.

Pharmacotherapy for Refractory and Super-Refractory Status Epilepticus in Adults

Patients with prolonged seizures that do not respond to intravenous benzodiazepines and a second-line anticonvulsant suffer from refractory status epilepticus and those with seizures that do not respond to continuous intravenous anesthetic anticonvulsants suffer from super-refractory status epilepticus. Both conditions are associated with significant morbidity and mortality. A strict pharmacological treatment regimen is urgently required, but the level of evidence for the available drugs is very low. Refractory complex focal status epilepticus generally does not require anesthetics, but all intravenous non-anesthetizing anticonvulsants may be used. Most descriptive data are available for levetiracetam, phenytoin and valproate. Refractory generalized convulsive status epilepticus is a life-threatening emergency, and long-term clinical consequences are eminent. Administration of intravenous anesthetics is mandatory, and drugs acting at the inhibitory gamma-aminobutyric acid (GABA)_A receptor such as midazolam, propofol and thiopental/pentobarbital are recommended without preference for one of those. One in five patients with anesthetic treatment does not respond and has super-refractory status epilepticus. With sustained seizure activity, excitatory N-methyl-d-aspartate (NMDA) receptors are increasingly expressed post-synaptically. Ketamine is an antagonist at this receptor and may prove efficient in some patients at later stages. Neurosteroids such as allopregnanolone increase sensitivity at GABA_A receptors; a Phase 1/2 trial demonstrated safety and tolerability, but randomized controlled data failed to demonstrate efficacy. Adjunct ketogenic diet may contribute to termination of difficult-to-treat status epilepticus. Randomized controlled trials are needed to increase evidence for treatment of refractory and super-refractory status epilepticus, but there are multiple obstacles for realization. Hitherto, prospective multicenter registries for pharmacological treatment may help to improve our knowledge.

Systemic Complications Following Status Epilepticus

PURPOSE OF REVIEW

Status epilepticus (SE) is a multisystem disorder. Initially, complications of a massive catecholamine release followed by the side effects of medical therapies, impact patients' outcomes. The aim of this article is to provide an updated summary of the systemic complications following SE.

RECENT FINDINGS

In recent years, the importance of the multifaceted nature of SE and its relationship with clinical outcomes has been increasingly recognized. The cumulative systemic effects of prolonged seizures and their treatment contribute to morbidity and mortality in this condition. Most systemic complications after SE are predictable. Anticipating their occurrence and respecting a number of simple guidelines may improve the prognosis of these patients.

Seizures - just the tip of the iceberg: Critical care management of super-refractory status epilepticus

Super-refractory status epilepticus (SRSE) is defined as status epilepticus (SE) that continues or recurs 24 h or more after the onset of anesthetic therapy, including those cases where SE recurs on the reduction or withdrawal of anesthesia. Although SRSE is a rare clinical problem, it is associated with high mortality and morbidity rates. This article reviews the treatment approaches and the systemic complications commonly encountered in patients with SRSE. As evident in our search of literature, therapy for SRSE and its complications have been based on clinical reports and expert opinions since there is a lack of controlled and randomized trials. Even though this complex condition starts as a neurological disorder, because of the associated systemic complications, it can be considered as a multisystem disorder requiring scrupulous attention and deliberate efforts to prevent, detect, and treat these systemic effects. We have critically reviewed the intensive care management for SRSE per se as well as its associated systemic complications. We believe that a good recovery can occur even after prolonged and severe SRSE as long as the systemic complications are detected early and managed appropriately.

Progressive development of cardiomyopathy following altered autonomic activity in status epilepticus

Seizures are associated with altered autonomic activity, which has been implicated in the development of cardiac dysfunction and structural damage. This study aimed to investigate the involvement of the autonomic nervous system in seizure-induced cardiomyopathy. Male Sprague-Dawley rats (320–350 g) were implanted with EEG/ECG electrodes to allow simultaneous telemetric recordings during seizures induced by intrahippocampal (2 nmol, 1 μl/min) kainic acid and monitored for 7 days. Seizure activity occurred in conjunction with increased heart rate (20%), blood pressure (25%), and QTc prolongation (15%). This increased sympathetic activity was confirmed by the presence of raised plasma noradrenaline levels at 3 h post-seizure induction. By 48 h post-seizure induction, sympathovagal balance was shifted in favor of sympathetic dominance, as indicated by both heart rate variability (LF/HF ratio of 3.5 ± 1.0) and pharmacological autonomic blockade. Functional cardiac deficits were evident at 7 and 28 days, as demonstrated by echocardiography showing a decreased ejection fraction (14% compared with control, P < 0.05) and dilated cardiomyopathy present at 28 days following seizure induction. Histological changes, including cardiomyocyte vacuolization, cardiac fibrosis, and inflammatory cell infiltration, were evident within 48 h of seizure induction and remained present for up to 28 days. These structural changes most probably contributed to an increased susceptibility to aconitine-induced arrhythmias. This study confirms that prolonged seizure activity results in acute and chronic alterations in cardiovascular control, leading to a deterioration in cardiac structure and function. This study further supports the need for modulation of sympathetic activity as a promising therapeutic approach in seizure-induced cardiomyopathy.

Evaluation of Cardiovascular Risk Factors in the Wistar Audiogenic Rat (WAR) Strain

Introduction

Risk factors for life-threatening cardiovascular events were evaluated in an experimental model of epilepsy, the Wistar Audiogenic Rat (WAR) strain.

Methods

We used long-term ECG recordings in conscious, one year old, WAR and Wistar control counterparts to evaluate spontaneous arrhythmias and heart rate variability, a tool to assess autonomic cardiac control. Ventricular function was also evaluated using the pressure-volume conductance system in anesthetized rats.

Results

Basal RR interval (RRi) was similar between WAR and Wistar rats (188±5 vs 199±6 ms). RRi variability strongly suggests that WAR present an autonomic imbalance with sympathetic overactivity, which is an isolated risk factor for cardiovascular events. Anesthetized WAR showed lower arterial pressure (92±3 vs 115±5 mmHg) and exhibited indices of systolic dysfunction, such as higher ventricle end-diastolic pressure (9.2±0.6 vs 5.6±1 mmHg) and volume (137±9 vs 68±9 μL) as well as lower rate of increase in ventricular pressure (5266±602 vs 7320±538 mmHg.s-1). Indices of diastolic cardiac function, such as lower rate of decrease in ventricular pressure (-5014±780 vs -7766±998 mmHg.s^-1) and a higher slope of the linear relationship between end-diastolic pressure and volume (0.078±0.011 vs 0.036±0.011 mmHg.μL), were also found in WAR as compared to Wistar control rats. Moreover, Wistar rats had 3 to 6 ventricular ectopic beats, whereas WAR showed 15 to 30 ectopic beats out of the 20,000 beats analyzed in each rat.

Conclusions

The autonomic imbalance observed previously at younger age is also present in aged WAR and, additionally, a cardiac dysfunction was also observed in the rats. These findings make this experimental model of epilepsy a valuable tool to study risk factors for cardiovascular events in epilepsy.

Prolonged atrial fibrillation precipitated by new-onset seizures and marijuana abuse

We report a case of prolonged atrial fibrillation (AF) precipitated by new-onset generalized tonic-clonic convulsions and marijuana abuse in a developmentally normal 18-year-old adolescent with a structurally normal heart. Our case highlights an interesting association and a unique pathophysiology between generalized tonic-clonic convulsions, marijuana abuse, and AF. We suggest that seizures and marijuana abuse should be considered in the differential diagnosis of the etiology of AF in children.

Potential links between neurological disease and Tako-Tsubo cardiomyopathy: a literature review

Tako-Tsubo cardiomyopathy (TTC), is defined as a fully reversible acute deterioration of left-ventricular (LV) function, which is mainly found in women after an episode of emotional or physical stress (e.g. psychosocial stress, sepsis, surgery). The underlying mechanisms remain unclear. There is evidence suggesting a possible link between neurological disease and TTC. The pathophysiology of the several neurologic diseases has been reviewed searching for possible mechanisms that could lead to TTC in these patients.

Utility of laboratory tests for children in the emergency department with a first seizure

OBJECTIVE

The objective of the study was to evaluate the factors associated with abnormal laboratory findings in patients visiting the emergency department (ED) after having their first seizure.

METHODS

We included ED patients with first seizures and divided them into groups based on normal and abnormal laboratory results for serum levels of sodium, potassium, calcium, and glucose. We evaluated the differences in age, sex, the presence of fever, the presence of gastrointestinal symptoms, the duration and pattern of the seizure, and whether the seizure was still present at the ED.

RESULTS

We evaluated 240 patients. Among them, abnormalities were found in 83 (34.8%) of 238 for serum sodium, 16 (6.7%) of 238 for potassium, 11 (6.2%) of 177 for calcium, and 121 (52.3%) of 231 for glucose. In the serum sodium and calcium group, no differences in associated factors between patients with and without abnormal laboratory results were found. However, results revealed differences in seizure duration between patients with and without abnormal laboratory glucose results (P = 0.005) and in age between patients with normal and abnormal potassium results (P = 0.002).

CONCLUSIONS

There was no significant association among the factors of sex, fever, gastrointestinal symptoms, seizure duration, and seizures in patients who came to the ED with electrolyte abnormalities after a first seizure. However, glucose level abnormalities may have an association with increased seizure duration. We still do not have any suggestions as to which associated factors should be considered when doing common blood examinations in these patients.

Management of refractory status epilepticus in adults: still more questions than answers

Refractory status epilepticus (RSE) is defined as status epilepticus that continues despite treatment with benzodiazepines and one antiepileptic drug. RSE should be treated promptly to prevent morbidity and mortality; however, scarce evidence is available to support the choice of specific treatments. Major independent outcome predictors are age (not modifiable) and cause (which should be actively targeted). Recent recommendations for adults suggest that the aggressiveness of treatment for RSE should be tailored to the clinical situation. To minimise intensive care unit-related complications, focal RSE without impairment of consciousness might initially be approached conservatively; conversely, early induction of pharmacological coma is advisable in generalised convulsive forms of the disorder. At this stage, midazolam, propofol, or barbiturates are the most commonly used drugs. Several other treatments, such as additional anaesthetics, other antiepileptic or immunomodulatory compounds, or non-pharmacological approaches (eg, electroconvulsive treatment or hypothermia), have been used in protracted RSE. Treatment lasting weeks or months can sometimes result in a good outcome, as in selected patients after encephalitis or autoimmune disorders. Well designed prospective studies of RSE are urgently needed.

Treatment strategies for refractory status epilepticus

PURPOSE OF REVIEW

Status epilepticus is one of the most common emergencies in neurology, and every third patient does not respond to adequate first-line treatment. Refractory status epilepticus may be associated with increased morbidity and mortality, and new treatment options are urgently required. This review critically discusses recently published data regarding the role of 'new' antiepileptic drugs, the efficacy and safety of anesthetic agents, and the overall clinical outcome that is an integral part of treatment decisions.

RECENT FINDINGS

In complex partial status epilepticus, levetiracetam may be administered after failure of first-line and/or second-line agents. Lacosamide may be an interesting new adjunct, but reliable data are pending. In the treatment of refractory generalized convulsive status epilepticus, propofol seems to be as efficient as barbiturates. The latter are associated with prolonged ventilation times due to redistribution kinetics, whereas the former bears the risk of propofol infusion syndrome if administered continuously. Even after prolonged treatment with anesthetics over weeks, survival with satisfactory functional outcome is possible.

SUMMARY

Unambiguous recommendations regarding treatment strategies for refractory status epilepticus are limited by a lack of reliable data. Therefore, randomized controlled trials or at least prospective observational studies based on strict protocols incorporating long-term outcome data are urgently required.

Methods for ECG evaluation of indicators of cardiac risk, and susceptibility to aconitine-induced arrhythmias in rats following status epilepticus

Lethal cardiac arrhythmias contribute to mortality in a number of pathological conditions. Several parameters obtained from a non-invasive, easily obtained electrocardiogram (ECG) are established, well-validated prognostic indicators of cardiac risk in patients suffering from a number of cardiomyopathies. Increased heart rate, decreased heart rate variability (HRV), and increased duration and variability of cardiac ventricular electrical activity (QT interval) are all indicative of enhanced cardiac risk. In animal models, it is valuable to compare these ECG-derived variables and susceptibility to experimentally induced arrhythmias. Intravenous infusion of the arrhythmogenic agent aconitine has been widely used to evaluate susceptibility to arrhythmias in a range of experimental conditions, including animal models of depression and hypertension, following exercise and exposure to air pollutants, as well as determination of the antiarrhythmic efficacy of pharmacological agents. It should be noted that QT dispersion in humans is a measure of QT interval variation across the full set of leads from a standard 12-lead ECG. Consequently, the measure of QT dispersion from the 2-lead ECG in the rat described in this protocol is different than that calculated from human ECG records. This represents a limitation in the translation of the data obtained from rodents to human clinical medicine. Status epilepticus (SE) is a single seizure or series of continuously recurring seizures lasting more than 30 min, and results in mortality in 20% of cases. Many individuals survive the SE, but die within 30 days. The mechanism(s) of this delayed mortality is not fully understood. It has been suggested that lethal ventricular arrhythmias contribute to many of these deaths. In addition to SE, patients experiencing spontaneously recurring seizures, i.e. epilepsy, are at risk of premature sudden and unexpected death associated with epilepsy (SUDEP). As with SE, the precise mechanisms mediating SUDEP are not known. It has been proposed that ventricular abnormalities and resulting arrhythmias make a significant contribution. To investigate the mechanisms of seizure-related cardiac death, and the efficacy of cardioprotective therapies, it is necessary to obtain both ECG-derived indicators of risk and evaluate susceptibility to cardiac arrhythmias in animal models of seizure disorders. Here we describe methods for implanting ECG electrodes in the Sprague-Dawley laboratory rat (Rattus norvegicus), following SE, collection and analysis of ECG recordings, and induction of arrhythmias during iv infusion of aconitine. These procedures can be used to directly determine the relationships between ECG-derived measures of cardiac electrical activity and susceptibility to ventricular arrhythmias in rat models of seizure disorders, or any pathology associated with increased risk of sudden cardiac death.

Lovastatin decreases the synthesis of inflammatory mediators in the hippocampus and blocks the hyperthermia of rats submitted to long-lasting status epilepticus

Statins may act on inflammatory responses, decreasing oxidative stress and also reducing temperature after a brain ischemic insult. Previous data have indicated that statins protect neurons from death during long-lasting status epilepticus (SE) and attenuate seizure behaviors in animals treated with kainic acid. In this context, the study described here aimed to investigate the effect of lovastatin on body temperature and on mRNA expression levels of hippocampal cytokines such as interleukin-1β, interleukin-6, tumor necrosis factor α, and kinin B1 and B2 receptors of rats submitted to pilocarpine-induced SE. Quantitative real-time polymerase chain reaction showed a significant decrease in mRNA expression of interleukin-1β, interleukin-6, tumor necrosis factor α, and kinin B1 receptor in animals with SE treated with lovastatin, compared with untreated animals with SE (P<0.001). Lovastatin also reduced SE-induced hyperthermia, indicating that mechanisms related to brain protection are triggered by this drug under conditions associated with acute excitotoxicity or long-lasting SE.

Status epilepticus induces cardiac myofilament damage and increased susceptibility to arrhythmias in rats

Status epilepticus (SE) is a seizure or series of seizures that persist for >30 min and often results in mortality. Death rarely occurs during or immediately following seizure activity, but usually within 30 days. Although ventricular arrhythmias have been implicated in SE-related mortality, the effects of this prolonged seizure activity on the cardiac function and susceptibility to arrhythmias have not been directly investigated. We evaluated myocardial damage, alterations in cardiac electrical activity, and susceptibility to experimentally induced arrhythmias produced by SE in rats. SE resulted in seizure-related increases in blood pressure, heart rate, and the first derivative of pressure, as well as modest, diffuse myocyte damage assessed by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling staining. Ten to twelve days following seizures, electrocardiographic recordings showed arrhythmogenic alterations in cardiac electrical activity, denoted by prolonged QT interval corrected for heart rate and QT dispersion. Finally, SE increased susceptibility to experimentally induced (intravenous aconitine) cardiac arrhythmias. These data suggest that SE produces tachycardic ischemia following the activation of the sympathetic nervous system, resulting in cardiac myofilament damage, arrhythmogenic alterations in cardiac electrical activity, and increased susceptibility to ventricular arrhythmias.

Status epilepticus produces chronic alterations in cardiac sympathovagal balance

PURPOSE

Status epilepticus (SE) activates the autonomic nervous system, increasing sympathetic nervous system control of cardiac function during seizure activity. However, lasting effects of SE on autonomic regulation of the heart, which may contribute to mortality following seizure activity, are unknown. Therefore, autonomic control of cardiac function was assessed following SE.

METHODS

Using Sprague-Dawley rats after 1-2 weeks of recovery from lithium-pilocarpine-induced SE or control procedures, we tested overall sympathovagal control of the heart, the individual contributions of the sympathetic and parasympathetic components of the autonomic nervous system, and baroreflex sensitivity.

RESULTS

SE induced a chronic shift in sympathovagal balance toward sympathetic dominance resulting from decreased parasympathetic activity. Baroreflex sensitivity to increased blood pressure was also decreased, likely resulting from diminished vagal activation.

DISCUSSION

Chronic alterations in autonomic regulation of cardiac function, characterized by increased sympathetic dominance, occur following SE and likely contribute to subsequent increased cardiac risk and mortality.

Kv4.2 knockout mice demonstrate increased susceptibility to convulsant stimulation

PURPOSE

Kv4.2 subunits contribute to the pore-forming region of channels that express a transient, A-type K(+) current (A-current) in hippocampal CA1 pyramidal cell dendrites. Here, the A-current plays an important role in signal processing and synaptic integration. Kv4.2 knockout mice show a near elimination of the A-current in area CA1 dendrites, producing increased excitability in this region. In these studies, we evaluated young adult Kv4.2 knockout mice for spontaneous seizures and the response to convulsant stimulation in the whole animal in vivo and in hippocampal slices in vitro.

METHODS

Electroencephalogram electrode-implanted Kv4.2 knockout and wild-type mice were observed for spontaneous behavioral and electrographic seizures. The latency to seizure and status epilepticus onset in Kv4.2 knockout and wild-type mice was assessed following intraperitoneal injection of kainate. Extracellular field potential recordings were performed in hippocampal slices from Kv4.2 knockout and wild-type mice following the bath application of bicuculline.

RESULTS

No spontaneous behavioral or electrographic seizures were observed in Kv4.2 knockout mice. Following kainate, Kv4.2 knockout mice demonstrated a decreased seizure and status epilepticus latency as well as increased mortality compared to wild-type littermates. The background strain modified the seizure susceptibility phenotype in Kv4.2 knockout mice. In response to bicuculline, slices from Kv4.2 knockout mice exhibited an increase in epileptiform bursting in area CA1 as compared to wild-type littermates.

DISCUSSION

These studies show that loss of Kv4.2 channels is associated with enhanced susceptibility to convulsant stimulation, supporting the concept that Kv4.2 deficiency may contribute to aberrant network excitability and regulate seizure threshold.

Generalised convulsive status epilepticus in Singapore: clinical outcomes and potential prognostic markers

PURPOSE

To study the characteristics, outcomes and prognostic markers of convulsive status epilepticus (SE) in Singapore.

METHODS

62 adult admissions to the National University Hospital Singapore from 2002 to 2005 were studied. Ethnicity, history of epilepsy, educational subnormality, neuroimaging, seizure duration, length of stay, Modified Rankin Scale (MRS) pre and post discharge, blood glucose, creatine kinase, potassium, white cell and platelet count were recorded. An MRS> or =3 at discharge was defined as a poor outcome. ROCs of significant variables were plotted to identify the best test cut-offs.

RESULTS

Mean age was 59.2 years (range 20-94). 75.9% patients had epilepsy. Mean length of stay was 14 days (range 1-75). Univariate analyses revealed age (p=0.01, OR 1.075, 95% CI 1.030-1.122), length of stay in ICU (p=0.03, OR 1.299, 95% CI 1.014-1.665) and hospital (p=0.014, OR 1.203, 95% CI 1.038-1.393) and hyperglycemia (p=0.045, OR 1.327, 95% CI 1.007-1.750) associated with poor outcome. Test cut-off values for prognostic markers were established: age> or =55 years (ROC 0.790, sensitivity 72.3, specificity 85.7, PPV9 4.4%, NPV 48.8%) and serum glucose> or =7 mmol/L (ROC 0.737, sensitivity 72.3, specificity 80.0, PPV 93.5%, NPV 36.4%). A discriminant model using these variables was then constructed with probability scores for poor outcome.

DISCUSSION

Age, hyperglycemia and length of stay in hospital influenced outcome from convulsive SE in the local population with hyperglycemia being a novel prognostic marker. Some prognostic markers cited in the literature differed, highlighting the possibility that these indicators may vary across population groups.

[Management of refractory status epilepticus from a neurologic and neuropediatric perspective]

Status epilepticus is a frequent neurologic emergency that is refractory to benzodiazepines and phenytoin in 60% to 70% of cases. Patients commonly require management in an intensive care unit incorporating aggressive treatment with intravenous anaesthetics. Treatment guidelines commonly comment on initial pharmacologic management in detail, as they can refer to data from randomised controlled trials. In contrast, recommendations for the management of refractory status epilepticus often are sparse, as they rely on data from retrospective or uncontrolled prospective studies only. Since status epilepticus is refractory in every third patient, a critical analysis of the available data and a review focussing on the further management of this condition are urgently needed. The Koenigstein Team, a panel of expert epileptologists and neuropediatricians, discussed at its 31(st) meeting in March 2006 the clinical and experimental aspects and implicit prognostic variables of refractory status epilepticus. Here we present the results of that discussion and state recommendations from a neurologic and neuropediatric perspective for current und future management of refractory status epilepticus.

The anaesthetic and intensive care of status epilepticus

PURPOSE OF REVIEW

Status epilepticus refractory to first and second-line anticonvulsants represents an outstanding challenge to the medical team. This review covers new insights into the anaesthetic and intensive care of status epilepticus.

RECENT FINDINGS

In the anaesthetic treatment of status epilepticus, barbiturates, midazolam, or propofol are the drugs of choice, but the lack of controlled prospective data as yet does not allow the recommendation of a preference for one of the substances, unequivocally. Recent observational studies reported on inhalational anaesthetics and supplementary nonanaesthetics such as levetiracetam or topiramate that may be administered if status epilepticus is not controlled by intravenous anaesthetics. Nonpharmacological approaches including resective surgery, brain stimulation, and hypothermia may be applied in selected patients, only. Psychogenic nonepileptic status epilepticus commonly mimics refractory generalized convulsive status epilepticus, and clinical features discerning the two conditions are presented. The underlying cause is the major contributor for a difficult-to-treat 'malignant' course of status epilepticus and together with age determines mortality and functional outcome.

SUMMARY

The common substances administered for the anaesthetic treatment of status epilepticus require assessment in a prospective randomized controlled trial. Alternative pharmacological or nonpharmacological approaches need further studies as well before they can be recommended as part of the therapeutic regime.

Aetiology, course and outcome of children admitted to paediatric intensive care with convulsive status epilepticus: a retrospective 5-year review

A retrospective case note study of the aetiology and course of children in convulsive status epilepticus (CSE) admitted to a large paediatric intensive care unit (PICU) was undertaken between January 1999 and April 2004. Status epilepticus was defined as a prolonged (>30 min) tonic-clonic seizure irrespective of whether the seizure had stopped prior to admission to PICU. During this period, 137 (74 male) children aged 1 month to 15 years were admitted to PICU with 147 episodes of status epilepticus. Forty-seven of the 137 children (34%) were admitted following a prolonged febrile seizure. Thirty-eight of the 137 children (28%) had a remote symptomatic cause for the CSE, 24 (18%) were admitted for an acute symptomatic cause and 15 (11%) were admitted with an acute exacerbation of a pre-existing idiopathic/cryptogenic epilepsy. Six children had a progressive encephalopathy and no cause was identified in the remaining 7 of the 137 children (5%). Forty-nine (36%) of the 137 children had pre-existing epilepsy. The mean duration of CSE was 44 min. Forty-nine (36%) children admitted to PICU who had received a benzodiazepine with either phenobarbital or phenytoin, required further treatment to terminate the presenting episode of CSE. Forty-two of these 49 were treated with thiopentone anaesthesia and the remaining 7 with a continuous infusion of midazolam, successfully terminating status in all. No child died. Of the 70 children considered to be previously neurologically and developmentally normal prior to admission, only 1 child demonstrated a new gross neurological abnormality at the time of latest follow-up. Seven patients (5%) developed new or de novo epilepsy.

Status epilepticus as an initial manifestation of neurosyphilis: a case report

Seizures and focal neurologic deficits may be the complications of neurosyphilis, but status epilepticus as a presenting picture of neurosyphilis is rare. We describe a 41-year-old man with an acute onset of expressive dysphasia, followed by persistent seizure state and severe complications of systemic medical problems. An extensive laboratory evaluation confirmed the diagnosis of neurosyphilis and diabetes mellitus. Brain magnetic resonance imaging showed edematous change in the left cingulate gyrus, left temporal lobe, and peri-Rolandic area, which suggested an inflammatory process. Due to varied clinical manifestations of neurosyphilis, we underscore the importance of considering neurosyphilis among the possible causes of status epilepticus and any central nervous system diseases.

Outcome of paediatric convulsive status epilepticus: a systematic review

We did a systematic review on the outcome of paediatric convulsive status epilepticus (CSE) and investigated the role of biological and non-biological variables in reported outcomes. The methodological quality of the 63 studies that met our inclusion criteria was assessed. Study design, type of study, and length of follow-up influenced the outcome. The studies with highest methodological quality are associated with better outcome: short-term mortality between 2.7% and 5.2% and morbidity other than epilepsy less than 15%. The incidence of subsequent epilepsy is not increased after cryptogenic CSE. Causal factor is the main determinant of outcome and the effect of age or duration is difficult to separate from the underlying cause. The risk of sequelae in unprovoked and febrile CSE is low. There is some evidence that CSE, especially febrile CSE, might cause hippocampal injury, although its role in the development of mesial temporal sclerosis is unknown.

Limbic Self-sustaining Status Epilepticus in Rats Is Not Associated with Hyperthermia

PURPOSE

To evaluate the impact of limbic status epilepticus on temperature.

METHODS

The perforant path in freely moving rats was stimulated electrically for 120 min to induce self-sustaining status epilepticus (SSSE). For 150 min after the end of stimulation, epidural temperature and electrographic and clinical seizure activity were assessed in animals with limbic and motor SSSE, as well as in animals without development of SE.

RESULTS

Temperature in all animals with SSSE was elevated by 1.5+/-0.8 degrees C after the end of stimulation compared with baseline values (p<0.01). In animals with pure limbic SE, temperature decreased continuously to baseline values over the 150-min period of observation. In contrast, in animals with motor SSSE, temperature remained elevated during continuing epileptic activity and was still significantly higher 150 min after the end of stimulation compared with baseline (p<0.01). In animals that did not develop SSSE, temperature was not changed after the end of electrical stimulation and in the 150 min thereafter compared with baseline values.

CONCLUSIONS

The results indicate that hyperthermia as seen in SE is the consequence of motor convulsions and not of epileptic activity itself, as seen in limbic SSSE.

A comparison of three NMDA receptor antagonists in the treatment of prolonged status epilepticus

Three different classes of NMDA receptor antagonists were compared for their effectiveness in terminating prolonged status epilepticus (SE), induced by continuous hippocampal stimulation. Animals were treated after 150 min of SE by intraperitoneal administration of increasing doses of 3-((R,S)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP), MK-801 (dizocilpine), ifenprodil, or saline. EEG recordings were used to determine seizure termination. The first experiment (n = 57 animals) determined the most effective anticonvulsant dose of each agent by determining its ability to terminate SE within the next 300 min. Five control rats treated with normal saline after 150 min of SE continued to exhibit continuous seizures for the next 300 min. All drugs were administered after 150 min of SE. CPP terminated seizures with an ED(50) of 6.4 mg/kg; the maximal effective dose was 15 mg/kg. MK-801 has an ED(50) of 1.4 mg/kg; the maximal effective dose was 2 mg/kg. Ifenprodil was maximally effective at 30 mg/kg. However, an ED(50) could not be calculated. In a subsequent experiment, the NMDA antagonists were compared for their ability to terminate prolonged SE within 60 min of their administration at the most effective dose. MK-801 (2.0 mg/kg) terminated SE in 6 of 10 animals within 60 min, CPP (15 mg/kg) terminated it in 1 of 9 animals; ifenprodil (30 mg/kg) did not terminate it in any of 9 animals treated. In the 300 min following administration, CPP (6/9) and MK-801 (6/10) were equally efficacious in terminating SE but ifenprodil (2/7) was less effective (P = 0.065, chi-square test). The results indicate that the non-competitive NMDA receptor antagonist MK-801 was superior to the competitive antagonist CPP and the pH-sensitive site antagonist ifenprodil, in terminating prolonged experimental SE.

Effect of sleep on epilepsy

There is an extremely intimate relationship between sleep and epilepsy. In this manuscript I will review the influence that sleep has on epilepsy. Sleep is a potent activator of interictal epileptiform discharges. Sharp waves are infrequent during wakefulness in benign focal epilepsy of childhood, but may occur in runs of several discharges per page in sleep. The interictal discharges become almost continuous in non-REM sleep in the syndrome of encephalopathy with electrical status epilepticus during slow wave sleep. In some patients with West syndrome a hypsarrhythmia pattern may only appear in sleep whereas in others there may be an increase in discharges in a semiperiodic fashion resulting in a burst-suppression like pattern. Seizures appear to have a very close relationship with sleep in certain epilepsy syndromes. In benign focal epilepsy of childhood the seizures occur almost exclusively in sleep, while supplementary sensorimototor area seizures tend to occur in clusters during sleep. Juvenile myoclonic epilepsy has a close relationship with the sleep-wake cycle with seizures tending to occur predominantly on awakening. I also discuss the role of sleep and sleep deprivation in the EEG evaluation of epilepsy.

Neuroprotective strategies in epilepsy

Dr. Carlen reviews the evidence that seizures may cause cell death and discusses possible strategies for preventing seizure-induced brain damage.

Prehospital Treatment of Status Epilepticus with Benzodiazepines Is Effective and Safe

Benzodiazepines are an effective and safe treatment of status epilepticus and serial seizures when used in an out-of-hospital setting. Intravenously administered lorazepam is somewhat superior to diazepam for the treatment of status epilepticus. Treatment of status epilepticus should be initiated when seizures have lasted 5-7 minutes.

Prehospital Treatment of Status Epilepticus with Benzodiazepines is Effective and Safe

Benzodiazepines are an effective and safe treatment of status epilepticus and serial seizures when used in an out-of-hospital setting. Intravenously administered lorazepam is somewhat superior to diazepam for the treatment of status epilepticus. Treatment of status epilepticus should be initiated when seizures have lasted 5–7 minutes.

[Pathophysiology of epileptic seizures and status epilepticus]

Primary and secondary epileptogenesis involves multiple genetic and acquired factors. Epileptogenesis is a complex result of combined factors including membrane factors, neurotransmitter and environmental factors. Ion channel-related diseases, GABA and glutamate dysfunction, and glial reaction intervene in different epileptic conditions. The understanding of the mechanisms which emphasize initiation and maintenance of status epilepticus (SE) are in progress. Prognosis of SE is related to the duration of epileptic activity and to the acute cerebral and systemic consequences. Delayed cellular and molecular alterations after SE are responsible for secondary epileptogenesis. Glutamate receptor activation is the main key point leading to an excessive intraneuronal accumulation of ionic calcium by which a cascade of reactions is induced. Apoptotic neuronal death, glial reaction axonal sprouting and neurogenesis contribute to a state of hyperexcitability and hypersynchrony. A better understanding of underlying mechanisms of epileptogenesis may serve the development of new drugs with both anticonvulsant and antiepileptic (prevention or neuroprotection) actions.

Nonconvulsive status epilepticus in theophylline toxicity

CASE REPORT

A 53-year-old cocaine user was on chronic therapy with theophylline, albuterol, and ipratropium for asthma and nifedipine for hypertension. Acute asthma treatment that increased the serum theophylline to 35 micrograms/mL was associated with tonic clonic seizures followed by bizarre, lateralized posturing. Electroencephalogram seizure activity lasting 10 days was consistent with nonconvulsive status epilepticus, Complex Partial, type II. Theophylline was considered the probable instigator of this underdiagnosed neurologic disorder.

Seizures

Seizures are one of the most common neurologic emergencies. This article reviews the emergency evaluation and treatment of seizures, including status epilepticus. Pseudoseizures related to drugs, alcohol, and pregnancy are also discussed.

Treatment of refractory status epilepticus with propofol: clinical and pharmacokinetic findings

PURPOSE

We compared propofol with high-dose barbiturates in the treatment of refractory status epilepticus (RSE) and propose a protocol for the administration of propofol in RSE in adults, correlating propofol's effect with plasma levels.

METHODS

Sixteen patients with RSE were included; 8 were treated primarily with high-dose barbiturates and 8 were treated primarily with propofol.

RESULTS

Both groups of patients had multiple medical problems and a subsequent high mortality. A smaller but not statistically significant fraction of patients had their seizures controlled with propofol (63%) than with high-dose barbiturate therapy (82%). The time from initiation of high-dose barbiturate therapy to attainment of control of RSE was longer (123 min) than the time to attainment of seizure control in the group receiving propofol (2.6 min, p = 0.002). Plasma concentrations of propofol associated with control of SE were 14 microM +/- 4 (2.5 microg/ml). Recurrent seizures were common when propofol infusions were suddenly discontinued but not when the infusions were gradually tapered.

CONCLUSIONS

If used appropriately, propofol infusions can effectively and quickly terminate many but not all episodes of RSE. Propofol is a promising agent for use in treating RSE, but more studies are required to determine its true value in comparison with other agents.

Status epilepticus in children and adults

Status epilepticus (SE) in children and adults is one of the most common neurology problems confronting the intensivist. Recognition of SE is usually straightforward, but may be complicated by the effects of other diseases or therapies. Emergent treatment is necessary to prevent further brain damage. This article reviews protocols for standard treatments of SE patients and includes recommendations for the management of refractory SE.

MR spectroscopic imaging and diffusion-weighted MRI for early detection of kainate-induced status epilepticus in the rat

Previous studies have shown that reduction of N-acetyl-aspartate (NAA) is correlated with the degree of neuronal loss at 3 days after kainate-induced status epilepticus in the rat. In this study, magnetic resonance spectroscopic imaging (MRSI), measurement of NAA and lactate, T2-weighted MRI, and diffusion-weighted MRI were used to study early alterations in rat piriform cortex at 12 and 26 h after kainate administration. The major findings are that decreased NAA signal, increased lactate signal, and decreased apparent diffusion coefficient (ADC) were observed at 12 h, with little evidence of histological and T2-weighted MRI changes. These results support the hypothesis that NAA, lactate signals, and ADC provide sensitive methods for detection of early and minimal brain damage in vivo.

Cardiac hypertrophy secondary to status epilepticus in the rat

Status epilepticus was induced in rats by sequential injections of lithium and pilocarpine. Seizure activity was aborted by a combination of MK-801 and diazepam, with status duration ranging from 3 to 180 min. When the hearts were examined 8-12 days later, rats that had experienced an episode of status epilepticus had significantly heavier hearts than did controls. The nature of the cardiac tissue changes was not examined, and deserves further study.