Diagnosis and treatment of status epilepticus on a neurological intensive care unit

The A to F of functional status in the acute setting: A scoping review

Functional status (FSt) describes the phenomenon of prolonged non-epileptic attacks that may be misidentified as Status Epilepticus (SE). The early differentiation between epileptic and functional status is crucial in order to avoid unnecessarily invasive and costly medical escalation in the latter group, including the hazards of overmedication, intubation and intensive care admission. The authors conducted a literature review of available studies describing cases of functional status to extract the common aspects of FSt seizure semiology, investigations used to differentiate from SE, and guidance for managing FSt. A search was carried out using Medline, Embase and PsychInfo databases and 3909 papers were extracted for review. 30 papers were found relevant for inclusion, describing 260 cases of FSt. FSt was found to occur more commonly in younger, female patients with a family history of epilepsy, co-morbid psychiatric diagnosis and following a recent traumatic event. Common clinical features of FSt during and after, the events were identified. While video-EEG remains the gold standard investigation for differentiating FSt from SE, many of the included studies considered the utility of other investigation modalities including serum markers and neuroimaging. One key shortcoming identified within the literature reviewed was a lack of well-defined guidance on the acute management of FSt. We offer an A-F step management plan for the immediate and longer term assessment and treatment of FSt.

Pre-hospital and emergency department treatment of convulsive status epilepticus in adults: an evidence synthesis

BACKGROUND

Convulsive status epilepticus is defined as ≥ 5 minutes of either continuous seizure activity or repetitive seizures without regaining consciousness. It is regarded as an emergency condition that requires prompt treatment to avoid hospitalisation and to reduce morbidity and mortality. Rapid pre-hospital first-line treatment of convulsive status epilepticus is currently benzodiazepines, administered either by trained caregivers in the community (e.g. buccal midazolam, rectal diazepam) or by trained health professionals via intramuscular or intravenous routes (e.g. midazolam, lorazepam). There is a lack of clarity about the optimal treatment for convulsive status epilepticus in the pre-hospital setting.

OBJECTIVES

To assess the current evidence on the clinical effectiveness and cost-effectiveness of treatments for adults with convulsive status epilepticus in the pre-hospital setting.

DATA SOURCES

We searched major electronic databases, including MEDLINE, EMBASE, PsycInfo®, CINAHL, CENTRAL, NHS Economic Evaluation Database, Health Technology Assessment Database, Research Papers in Economics, and the ISPOR Scientific Presentations Database, with no restrictions on publication date or language of publication. Final searches were carried out on 21 July 2020.

REVIEW METHODS

Systematic review of randomised controlled trials assessing adults with convulsive status epilepticus who received treatment before or on arrival at the emergency department. Eligible treatments were any antiepileptic drugs offered as first-line treatments, regardless of their route of administration. Primary outcomes were seizure cessation, seizure recurrence and adverse events. Two reviewers independently screened all citations identified by the search strategy, retrieved full-text articles, extracted data and assessed the risk of bias of the included trials. Results were described narratively.

RESULTS

Four trials (1345 randomised participants, of whom 1234 were adults) assessed the intravenous or intramuscular use of benzodiazepines or other antiepileptic drugs for the pre-hospital treatment of convulsive status epilepticus in adults. Three trials at a low risk of bias showed that benzodiazepines were effective in stopping seizures. In particular, intramuscular midazolam was non-inferior to intravenous lorazepam. The addition of levetiracetam to clonazepam did not show clear advantages over clonazepam alone. One trial at a high risk of bias showed that phenobarbital plus optional phenytoin was more effective in terminating seizures than diazepam plus phenytoin. The median time to seizure cessation from drug administration varied from 1.6 minutes to 15 minutes. The proportion of people with recurrence of seizures ranged from 10.4% to 19.1% in two trials reporting this outcome. Across trials, the rates of respiratory depression among participants receiving active treatments were generally low (from 6.4% to 10.6%). The mortality rate ranged from 2% to 7.6% in active treatment groups and from 6.2% to 15.5% in control groups. Only one study based on retrospective observational data met the criteria for economic evaluation; therefore, it was not possible to draw any robust conclusions on cost-effectiveness.

LIMITATIONS

The limited number of identified trials and their differences in terms of treatment comparisons and outcomes hindered any meaningful pooling of data. None of the included trials was conducted in the UK and none assessed the use of buccal midazolam or rectal diazepam. The review of economic evaluations was hampered by lack of suitable data.

CONCLUSIONS

Both intravenous lorazepam and intravenous diazepam administered by paramedics are more effective than a placebo in the treatments of adults with convulsive status epilepticus, and intramuscular midazolam is non-inferior to intravenous lorazepam. Large well-designed clinical trials are needed to establish which benzodiazepines are more effective and preferable in the pre-hospital setting.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42020201953.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Evidence Synthesis programme and will be published in full in Health Technology Assessment; Vol. 26, No. 20. See the NIHR Journals Library website for further project information.

Psychogenic nonepileptic seizures treated as epileptic seizures in the emergency department

OBJECTIVES

We aimed to estimate the rate of psychogenic nonepileptic seizures (PNES) among patients presenting to an emergency department with presumed seizures. We also wanted to identify factors that can assist health care professionals in determining whether these events are likely to be epileptic or nonepileptic.

METHODS

We performed two retrospective audits on patients who were treated for seizures in the department of emergency medicine at the Princess Alexandra Hospital, Brisbane, Australia. Exploratory analyses and logistic regressions were conducted to investigate the characteristics of the presentations and the relationships between our variables of interest.

RESULTS

In the group of all presentations with presumed seizures over a 3-month period (n = 157), a total of 151 presentations (96.2%) presentations were given a primary diagnosis of epileptic seizures. Of these 151 presentations, only 84 (55.6%) presented with epileptic seizures and 40 (26.5%) actually presented with PNES. In the group of patients who presented with prolonged and/or multiple events (n = 213) over a 1-year period, 196 (92.0%) were treated as epileptic seizures. Of these 196 presentations, only 85 (43.4%) presented with epileptic seizures and 97 (49.5%) actually presented with PNES. Several factors were identified to help risk stratify between epileptic seizures and PNES: Duration of events and of the postictal phase, number of events, presence of a structural brain pathology, mental health history, lactate levels and presence of tongue bite, incontinence, and/or vomiting.

SIGNIFICANCE

A large proportion of people who present to emergency departments with events resembling epileptic seizures actually have PNES rather than epilepsy-particularly those patients who present with prolonged and/or multiple events. The rate of misdiagnosis was high. Efforts need to be made to recognize patients with psychogenic nonepileptic seizures earlier and diagnose them correctly to avoid unnecessary iatrogenic harm and to provide adequate treatment.

Functional neurological disorder in the emergency department

We provide a narrative review of functional neurological disorder (FND, or conversion disorder) for the emergency department (ED). Diagnosis of FND has shifted from a "rule-out" disorder to one now based on the recognition of positive clinical signs, allowing the ED physician to make a suspected or likely diagnosis of FND. PubMed, Google Scholar, academic books, and a hand search through review article references were used to conduct a literature review. We review clinical features and diagnostic pitfalls for the most common functional neurologic presentations to the ED, including functional limb weakness, functional (nonepileptic) seizures, and functional movement disorders. We provide practical advice for discussing FND as a possible diagnosis and suggestions for initial steps in workup and management plans.

The first-line management of psychogenic non-epileptic seizures (PNES) in adults in the emergency: a practical approach

Distinguishing non-epileptic events, especially psychogenic non-epileptic seizures (PNES), from epileptic seizures (ES) constitutes a diagnostic challenge. Misdiagnoses are frequent, especially when video-EEG recording, the gold-standard for PNES confirmation, cannot be completed. The issue is further complicated in cases of combined PNES with ES. In emergency units, a misdiagnosis can lead to extreme antiepileptic drug escalade, unnecessary resuscitation measures (intubation, catheterization, etc.), as well as needless biologic and imaging investigations. Outside of the acute window, an incorrect diagnosis can lead to prolonged hospitalization or increase of unhelpful antiepileptic drug therapy. Early recognition is thus desirable to initiate adequate treatment and improve prognosis. Considering experience-based strategies and a thorough review of the literature, we aimed to present the main clinical clues for physicians facing PNES in non-specialized units, before management is transferred to epileptologists and neuropsychiatrists. In such conditions, patient recall or witness-report provide the first orientation for the diagnosis, recognizing that collected information may be inaccurate. Thorough analysis of an event (live or based on home-video) may lead to a clinical diagnosis of PNES with a high confidence level. Indeed, a fluctuating course, crying with gestures of frustration, pelvic thrusting, eye closure during the episode, and the absence of postictal confusion and/or amnesia are highly suggestive of PNES. Moreover, induction and/or inhibition tests of PNES have a good diagnostic value when positive. Prolactinemia may also be a useful biomarker to distinguish PNES from epileptic seizures, especially following bilateral tonic-clonic seizures. Finally, regardless the level of certainty in the diagnosis of the PNES, it is important to subsequently refer the patient for epileptological and neuropsychiatric follow-up.

The coexistence of psychogenic nonepileptic and epileptic seizures in the same patient is more frequent than expected: Is there any clinical feature for defining these patients?

OBJECTIVES

This study aimed to investigate the prevalence of psychogenic nonepileptic seizures (PNES) and PNES-epilepsy coexistence within all video-electroencephalography (EEG) monitoring unit (VEMU) referrals and to identify semiological and electrophysiological features to differentiate patients with PNES-epilepsy coexistence from PNES-only.

METHODS

We retrospectively reviewed medical files, VEMU reports, and videos of 1983 adult patients. Demographical, historical, clinical, neuroimaging, and electrophysiological parameters of all patients were recorded. We classified patients into five groups as definite PNES-only, definite PNES-epilepsy coexistence, definite PNES-probable epilepsy coexistence, probable PNES-definite epilepsy coexistence, and probable PNES-only. We defined a "definite" group when we saw the ictal EEG and/or video recording of the seizure. The "probable" term is used when there is strong evidence from the history of a particular seizure type and suggestive interictal EEGs without video recordings.

RESULTS

Two hundred and three of 1983 patients (10.23%) had PNES. Sixty-six of patients with PNES (32.51%) had definite PNES-epilepsy coexistence. When probable cases were included, the PNES-epilepsy coexistence ratio was 53.69% within all patients with PNES. The prevalence of PNES-epilepsy coexistence was 3.32% within all our VEMU referrals. Lower high school graduation rate, earlier age of disease onset, history of status epilepticus, febrile convulsion and brain surgery, use of three or more antiepileptic drugs, and abnormal magnetic resonance imaging (MRI) findings supported PNES-epilepsy coexistence (p < 0.05). On the contrary, seizure duration longer than 10 min was in favor of PNES-only (p < 0.05).

CONCLUSIONS

The prevalence of PNES-epilepsy coexistence might be more frequent in VEMUs than expected. Some demographic and semiological features and electrophysiological findings might be useful in differentiating patients with PNES-epilepsy coexistence from patients with PNES-only.

PNESSE 1: Psychogenic status and status epilepticus: Could they be distinguished retrospectively? A survey among neurologists

OBJECTIVE

The aim of this study was to evaluate neurologists' reliability in recognizing retrospectively a diagnosis of psychogenic status and status epilepticus (SE) based solely on clinical semiology, as reported in medical charts.

METHODS

This is a retrospective analysis of medical records of patients with suspected SE, diagnosed with psychogenic status and SE, proven by video-electroencephalography (EEG) monitoring, over a two-year period, from January 1st 2012 to December 31st 2013. Eight additional patients outside this time frame were included in this series because they had video-EEG proven psychogenic status, and they met all the inclusion criteria. The group with SE was divided into symptomatic SE (SSE) if a precipitating factor was identified, and undetermined SE (USE) if none were identified. Twenty-two neurologists from the CHU de Grenoble-Alpes were asked to fill out a survey where they were asked to score, for each patient, their agreement, using Likert scales, for the respective diagnoses of psychogenic status and SE. Their opinions were based on a provided written sheet summarizing the clinical description of the event and patients' clinical context. Neurologists were blinded to video-EEG monitoring results and final diagnosis. The level of agreement, disagreement, and the homogeneity of neurologist's responses according to the final diagnosis were then calculated. Finally, clinical data, as provided in the event's clinical description and context, considered as highly relevant by neurologists to establish an accurate diagnosis were gathered.

RESULTS

Eighteen neurologists completed the survey for 48 patients, including 11 diagnosed with psychogenic status and 37 with SE (30 with SSE and 7 with USE). For patients diagnosed with SE, the presence of a precipitating factor increased the likelihood and the homogeneity among neurologists of a diagnosis of SE (77%), with a specificity (Sp) of 96% and a positive predictive value of 95%. The lack of a precipitating factor significantly decreased the diagnosis likelihood of SE (55%) with a predictive value of 82%. For patients diagnosed with psychogenic status, most of neurologists agreed with the diagnosis of psychogenic status (69%) with a predictive value of 82%, although heterogeneity in the diagnosis was found. According to neurologists participating in this study, most significant terms, found in the medical charts, helping to distinguish SE from psychogenic status were "stereotypical movements", "limb myoclonus", "epilepsy", and "vigilance alteration". To differentiate psychogenic status from SE, most relevant terms used by neurologists were "resistance to eyes opening", "anarchic movements", "prolonged motor manifestations", "limb tremor" and "opisthotonus". However, analysis of the distribution of the terms among the different groups (SSE, USE, and psychogenic status) showed no significant difference.

SIGNIFICANCE

This study is in line with previous literature highlighting the difficulty in retrospectively differentiating SE from psychogenic status based on clinical events description recorded in the medical chart.

Potential consequences of high-dose infusion of ketamine for refractory status epilepticus: case reports and systematic literature review

Our goal was to provide comprehensive data on the effectiveness of ketamine in refractory status epilepticus (RSE) and to describe the potential consequences of long-term ketamine infusion. Ketamine, an N-methyl D-aspartate (NMDA) receptor antagonist, blocks excitatory pathways contributing to ongoing seizure. While ketamine use is standard in anaesthetic induction, no definitive protocol exists for its use in RSE, and little is known about its adverse effects in long-term, high-dose administration. We present two cases of RSE that responded rapidly to ketamine infusion, both with fatal outcomes secondary to metabolic acidosis and cardiovascular collapse. We performed a systematic review of the application and consequences of ketamine use in RSE. PubMed, Ovid, MEDLINE and PMC were searched for articles describing ketamine treatment for RSE according to a predetermined search strategy and inclusion criteria. The systematic review revealed wide discrepancies in ketamine dosing (infusion maintenance dose range 0.0075-10.5 mg/kg/hour), but good outcomes in medically managed RSE (75% of studies reported moderate or complete seizure control in adults, 62.5% in paediatrics). Additionally, literature review elucidated a potentially causal relationship between prolonged ketamine infusion and both cardiovascular and metabolic dysregulation. Ketamine is effective in RSE by antagonising excitotoxic NMDA receptors. However, there is high variability in ketamine dosing and scarce data on its safety in long-term infusion. Metabolic acidosis and haemodynamic instability associated with the use of long-term, high-dose ketamine infusions must be of concern to clinicians administering ketamine to critically ill patients.

Ketamine for Refractory Status Epilepticus: A Systematic Review

BACKGROUND

Ketamine is an emerging third-line medication for refractory status epilepticus, a medical and neurological emergency requiring prompt and appropriate treatment. Owing to its pharmacological properties, ketamine represents a practical alternative to conventional anaesthetics.

OBJECTIVE

The objective of this study was to assess the efficacy and safety of ketamine to treat refractory status epilepticus in paediatric and adult populations.

METHODS

We conducted a literature search using the PubMed database, Cochrane Database of Systematic Reviews and ClinicalTrials.gov website.

RESULTS

We found no results from randomised controlled trials. The literature included 27 case reports accounting for 30 individuals and 14 case series, six of which included children. Overall, 248 individuals (29 children) with a median age of 43.5 years (range 2 months to 67 years) were treated in 12 case series whose sample size ranged from 5 to 67 patients (median 11). Regardless of the status epilepticus type, ketamine was twice as effective if administered early, with an efficacy rate as high as 64% in refractory status epilepticus lasting 3 days and dropping to 32% when the mean refractory status epilepticus duration was 26.5 days. Ketamine doses were extremely heterogeneous and did not appear to be an independent prognostic factor. Endotracheal intubation, a negative prognostic factor for status epilepticus, was unnecessary in 12 individuals (10 children), seven of whom were treated with oral ketamine for non-convulsive status epilepticus.

CONCLUSIONS

Although ketamine has proven to be effective in treating refractory status epilepticus, available studies are hampered by methodological limitations that prevent any firm conclusion. Results from two ongoing studies (ClinicalTrials.gov identification number: NCT02431663 and NCT03115489) and further clinical trials will hopefully confirm the better efficacy and safety profile of ketamine compared with conventional anaesthetics as third-line therapy in refractory status epilepticus, both in paediatric and adult populations.

Psychogenic non-epileptic seizures: aetiology, diagnosis and management

Psychogenic non-epileptic seizures (PNES) have a significant impact on most patients in terms of distress, disability, loss of income and iatrogenic harm. Three-quarters of patients with PNES are initially misdiagnosed and treated for epilepsy. Misdiagnosis exposes patients to multiple iatrogenic harms and prevents them from accessing psychological treatment. In most cases, the patient's history (and witness accounts) should alert clinicians to the likely diagnosis of PNES. Since this diagnosis may be resisted by patients and may involve ‘un-diagnosing’ epilepsy, video-electroencephalogram recording of typical seizures is often helpful. The underlying causes of PNES are diverse: a model combining predisposing, precipitating and perpetuating factors is a useful way of conceptualising their aetiology. The initial step of treatment should be to limit iatrogenic harm. There is some evidence for the effectiveness of psychotherapy.

An update on the recognition and treatment of non-convulsive status epilepticus in the intensive care unit

INTRODUCTION

Non-convulsive status epilepticus (NCSE) is a complex and diverse condition which is often an under-recognised entity in the intensive care unit. When NCSE is identified the optimal treatment strategy is not always clear. Areas covered: This review is based on a literature review of the key literature in the field over the last 5-10 years. The articles were selected based on their importance to the field by the authors. Expert commentary: This review discusses the complex situations when a neurological consultation may occur in a critical care setting and provides an update on the latest evidence regarding the recognition of NCSE and the decision making around determining the aggressiveness of treatment. It also considers the ictal-interictal continuum of conditions which may be met with, particularly in the era of continuous EEG, and provides an approach for dealing with these. Suggestions for how the field will develop are discussed.

How reliable is ictal duration to differentiate psychogenic nonepileptic seizures from epileptic seizures?

We sought to investigate (1) differences in ictal duration between psychogenic nonepileptic seizures (PNES) and epileptic seizures (ES), (2) the odds of being PNES when seizures last ≥5min, and (3) the value of ictal duration as a diagnostic test to differentiate PNES from ES. We retrospectively reviewed video-EEG recordings and tabulated ictal durations of all PNES and ES. We estimated the mean ictal durations of PNES and ES using linear mixed models. The odds of being PNES when seizures last ≥5min were estimated using logistic regression. We used receiver operating characteristics (ROC) curves to study the overall diagnostic accuracy of ictal duration in differentiating PNES from ES. We studied 441 ES and 341 PNES recorded from 138 patients. The mean ictal duration of PNES (148.7s, 95% CI: 115.2-191.8) was significantly longer (p<0.001) than that of ES (47.7s, 95% CI: 37.6-60.6). The odds of being PNES was about 24 times higher (Odds ratio: 23.8, 95% CI: 7.9-71.3) when the ictal duration was ≥5min. The ROC curve yielded an area under the curve of 0.80 (95% CI 0.73-0.88). Youden's index identified 123.5s as the optimal threshold to diagnose PNES with 65% sensitivity and 93% specificity. Our results indicate that ictal duration is a useful test to raise suspicion of PNES. When a seizure lasts ≥5min, it is 24 times more likely to be PNES with the potential risk of misdiagnosis as status epilepticus.

25 years of advances in the definition, classification and treatment of status epilepticus

PURPOSE

Status epilepticus (SE) requires not only urgent symptomatic treatment with antiepileptic drugs but also rapid identification and treatment of its cause. This narrative review summarizes the most important advances in classification and treatment of SE.

METHOD

Data sources included MEDLINE, EMBASE, ClinicalTrials.gov, and back tracking of references in pertinent studies, reviews, and books.

RESULTS

SE is now defined as "a condition resulting either from the failure of the mechanisms responsible for seizure termination or from the initiation of mechanisms, which lead to abnormally, prolonged seizures (after time point t1). It is a condition, which can have long-term consequences (after time point t2), including neuronal death, neuronal injury, and alteration of neuronal networks, depending on the type and duration of seizures." A new diagnostic classification system of SE introduces four axes: semiology, aetiology, EEG correlates, and age. For the acute treatment intravenous benzodiazepines (lorazepam, diazepam, clonazepam) and intramuscular midazolam appear as most effective treatments for early SE. In children, buccal or intranasal midazolam are useful alternatives. In established SE intravenous antiepileptic drugs (phenytoin, valproate, levetiracetam, phenobarbital, and lacosamide) are in use. Treatment options in refractory SE are intravenous anaesthetics; ketamine, magnesium, steroids and other drugs have been used in super-refractory SE with variable outcomes.

CONCLUSION

Over the past 25 years major advances in definition, classification and understanding of its mechanisms have been achieved. Despite this up to 40% of patients in early status cannot be controlled with first line drugs. The treatment of super-refractory status is still an almost evidence free zone.

How do doctors in training react to seizures?

BACKGROUND AND AIMS

There are scant data on how doctors approach seizures in the acute setting. We sought to study (a) exposure to seizure disorders as well as relevant training and (b) reactions to seizures in the acute setting, among medical residents undergoing physician training.

METHODS

The exposure to and training on seizure disorders were assessed using a structured questionnaire first. Then, they were tested with 20 videos consisting of 10 epileptic seizures (ESs) and 10 psychogenic nonepileptic seizures (PNESs). After each video, we asked three questions to test (a) the diagnosis and the practice of administration of benzodiazepines to terminate the seizure, (b) the estimation of seizure duration, and (c) the practice of intubation. The accuracy of diagnosis was measured by the area under the summary receiver operating characteristics curve (AUC). The difference between true seizure duration and estimated duration was evaluated using paired-sample t-test.

RESULTS

A total of 48 trainees participated in the study. The majority witnessed seizures in movies (37, 77.1%) and television (35, 72.9%). Only 12 (25%) received bedside teaching on seizure disorders. Their diagnostic accuracy of seizures was very poor (AUC=0.54). Participants significantly underestimated the duration of seizures. Thirty-five doctors made an illogical decision to intubate but not to terminate the seizure with intravenous benzodiazepine.

CONCLUSIONS

The diagnostic accuracy of seizures is poor among trainees, and their estimates of seizure duration are unreliable. Our study highlights potential pitfalls in the acute management of seizures and the need for more training on seizure disorders.

(S)-Ketamine in Refractory and Super-Refractory Status Epilepticus: A Retrospective Study

OBJECTIVE

The aim was to describe the safety and efficacy of (S)-ketamine [(S)-KET] in a series of patients with refractory and super-refractory status epilepticus (RSE and SRSE) in a specialized neurological intensive care unit (NICU).

METHODS

We retrospectively analyzed the data of patients with RSE and SRSE treated with (S)-KET in the NICU, Salzburg, Austria, from 2011 to 2015. Data collection included demographic features, clinical presentation, diagnosis, electroencephalogram (EEG) data, anticonvulsant treatment, timing, and duration of treatment with (S)-KET. Outcomes were seizure control and death.

RESULTS

A total of 42 patients (14 women) with RSE and SRSE were treated with (S)-KET. The median duration of status epilepticus (SE) was 10 days [first quartile (Q1) 5.0, Q3 21.0]; the median latency from SE onset to the first administration of (S)-KET was 3 days (Q1 2.0, Q3 6.8). Prior to (S)-KET administration, patients had received a median of two (Q1 2.0, Q3 3.0) anesthetics and three (Q1 2.0, Q3 4.0) antiepileptic drugs. Forty percent of patients (17/42) received propofol: 65 % prior to (S)-KET; 35 % at the same time with (S)-KET. Seven patients received a median bolus of (S)-KET of 200 mg (Q1 200, Q3 250) followed by a continuous infusion, while 35 started with a continuous infusion (maximum rate median 2.55 mg/kg/h; Q1 2.09, Q3 3.22). In 64 % of patients (27/42), (S)-KET was the last drug before SE cessation; in five patients, it was given with propofol at the same time. Median duration of administration was 4 days (Q1 2.0, Q3 6.8). Overall (S)-KET treatment was well tolerated, adverse effects were not observed, and overall mortality was 45.2 %.

CONCLUSIONS

Treatment of SRSE in adult patients with (S)-KET led to resolution of status in 64 %. No adverse events were found, indicating a favorable safety profile.

Pharmacotherapy for Status Epilepticus

Status epilepticus (SE) represents the most severe form of epilepsy. It is one of the most common neurologic emergencies, with an incidence of up to 61 per 100,000 per year and an estimated mortality of 20 %. Clinically, tonic-clonic convulsive SE is divided into four subsequent stages: early, established, refractory, and super-refractory. Pharmacotherapy of status epilepticus, especially of its later stages, represents an "evidence-free zone," due to a lack of high-quality, controlled trials to inform clinical decisions. This comprehensive narrative review focuses on the pharmacotherapy of SE, presented according to the four-staged approach outlined above, and providing pharmacological properties and efficacy/safety data for each antiepileptic drug according to the strength of scientific evidence from the available literature. Data sources included MEDLINE and back-tracking of references in pertinent studies. Intravenous lorazepam or intramuscular midazolam effectively control early SE in approximately 63-73 % of patients. Despite a suboptimal safety profile, intravenous phenytoin or phenobarbital are widely used treatments for established SE; alternatives include valproate, levetiracetam, and lacosamide. Anesthetics are widely used in refractory and super-refractory SE, despite the current lack of trials in this field. Data on alternative treatments in the later stages are limited. Valproate and levetiracetam represent safe and effective alternatives to phenobarbital and phenytoin for treatment of established SE persisting despite first-line treatment with benzodiazepines. To date there are no class I data to support recommendations for most antiepileptic drugs for established, refractory, and super-refractory SE. Limiting the methodologic heterogeneity across studies is required and high-class randomized, controlled trials to inform clinicians about the best treatment in established and refractory status are needed.

YouTube as a potential learning tool to help distinguish tonic-clonic seizures from nonepileptic attacks

Medical students are increasingly turning to the website YouTube as a learning resource. This study set out to determine whether the videos on YouTube accurately depict the type of seizures that a medical student may search for. Two consultant epileptologists independently assessed the top YouTube videos returned following searches for eight terms relating to different categories of seizures. The videos were rated for their technical quality, concordance of diagnosis with an epileptologist-assigned diagnosis, and efficacy as a learning tool for medical education. Of the 200 videos assessed, 106 (63%) met the inclusion criteria for further analysis. Technical quality was generally good and only interfered with the diagnostic process in 8.5% of the videos. Of the included videos, 40.6-46.2% were judged to depict the purported diagnosis with moderate agreement between raters (75% agreement, κ=0.50). Of the videos returned after searching "tonic-clonic seizure", 28.6-35.7% were judged to show nonepileptic seizures with almost perfect interrater agreement (92.9% agreement, κ=0.84). Of the videos returned following the search "pseudoseizure", 77.8-88.9% of videos were judged to show nonepileptic seizures with substantial agreement (88.9% agreement, κ=0.61). Across all search terms, 19.8-33% of videos were judged as potentially useful as a learning resource, with fair agreement between raters (75.5% agreement, κ=0.38). These findings suggest that the majority of videos on YouTube claiming to show specific seizure subtypes are inaccurate, and YouTube should not be recommended as a learning tool for students. However, a small group of videos provides excellent demonstrations of tonic-clonic and nonepileptic seizures, which could be used by an expert teacher to demonstrate the difference between epileptic and nonepileptic seizures.

Psychogenic non-epileptic seizures in an Irish tertiary referral centre for epilepsy

Objectives: To examine the prevalence, psychiatric co-morbidity and management of psychogenic non-epileptic seizures (PNES) in patients admitted to a tertiary referral Epilepsy Monitoring Unit (EMU).

Methods: Medical records of patients admitted to the EMU between 2003 and 2005 were examined and data from neurological, neuropsychiatric and neuropsychological assessments were analysed.

Results: Over a three year period 224 patients were referred to the EMU and 44 (20%) were diagnosed with psychogenic non-epileptic seizures (PNES). A total of 13 people (6%) were diagnosed with both PNES and epilepsy. Of those diagnosed with PNES 34 (75%) were referred to psychology services for cognitive behavioural therapy (CBT) and 26 (58%) were followed-up by psychiatry services.

Conclusions: The prevalence rates for PNES and co-existing PNES and epilepsy are consistent with previous reports. Rates of psychiatric co-morbidity were less than would be expected in this clinical population. Clear evidence-based guidelines to manage people with PNES are required.

Requirement for cardiac telemetry during intravenous phenytoin infusion: guideline fact or guideline fiction?

Guidelines recommend the use of cardiac telemetry when phenytoin is administered intravenously. Clinical areas where telemetry is available may not always be the most suitable place to monitor and treat these sick patients. We sought to clarify the evidence regarding the need for cardiac telemetry during intravenous infusion of phenytoin.

Early ketamine to treat refractory status epilepticus

BACKGROUND

Management of refractory status epilepticus (SE) involves administration of intravenous γ-aminobutyric acid (GABA(A)) receptor agonists, such as benzodiazepines, barbiturates, or propofol. Animal models suggest that reductions in synaptic GABA(A) receptors may cause these drugs to become less effective as the duration of SE increases. This may explain the large doses that are commonly required to control seizures, which in turn contributes to a high incidence of complications, including hypotension and the need for vasopressors. In contrast, expression of excitatory N-methyl-D-aspartate (NMDA) receptors increases with prolonged SE and their stimulation by glutamate may propagate seizure activity. Ketamine is a NMDA-receptor antagonist that is considered promising as treatment for refractory SE. Compared with other anaesthetic drugs, ketamine produces less hypotension.

METHODS

This report describes a patient who developed worsening hypotension with escalating doses of midazolam and propofol in the context of non-convulsive SE. He was therefore treated with ketamine within hours of being diagnosed.

RESULTS

Ketamine was immediately efficacious at reducing the frequency, amplitude, and duration of seizures. The dose was rapidly titrated upwards using quantitative continuous EEG monitoring, until seizures were completely abolished. SE did not recur with weaning of sedatives and he went on to have an excellent recovery. A small number of previous reports have found ketamine to abort late SE. In most cases, ketamine was administered several days into the course, and outcomes were poor even though seizures were controlled.

CONCLUSION

Larger series and phase I clinical trial(s) of ketamine for treatment of refractory SE seem warranted.

When do psychogenic nonepileptic seizures occur on a video/EEG telemetry unit?

To maximize the efficiency of diagnostic video/EEG telemetry, we retrospectively studied the occurrence of clinical events during admission in 254 patients. One hundred fifty-nine patients had psychogenic nonepileptic seizures (PNES) and 95 had epileptic seizures (ES). Twenty-five with PNES and none with ES had an event before or during electrode placement (P<0.0001). In the remaining 229, the initial event occurred within 48 hours of electrode placement in 98.5% patients with PNES and 100.0% of patients with ES. Time to occurrence of initial event did not differ between groups (P=0.69). 17.1% patients with PNES and 51.6% with ES had events between 12 AM and 6 AM (P=0.001). In conclusion, during diagnostic video/EEG telemetry, most patients who experience PNES or ES have diagnostic, typical events within 2 days. Although time to initial event after electrode placement does not differ between diagnoses, events prior to or during placement are most likely PNES and events at night are most likely ES.

Stertorous breathing is a reliably identified sign that helps in the differentiation of epileptic from psychogenic non-epileptic convulsions: An audit

Stertorous breathing may occur after epileptic convulsions, but does not typically occur after psychogenic non-epileptic convulsions. During an 18-month audit at a tertiary referral centre in the United Kingdom, we analysed 75 convulsions arising in 45 patients and found that nursing and ancillary staff can be easily trained to reliably identify the presence or absence of stertorous breathing after a convulsion. No patient with a final diagnosis of purely psychogenic non-epileptic seizures (17 out of 45 patients) was judged to have stertorous respiration. Stertorous breathing was present in 41 out of 44 interpretable video recordings from patients with epileptic convulsions proven on videotelemetry. We suggest that a history or evidence (e.g. video) of stertorous breathing may help in distinguishing epileptic from psychogenic non-epileptic convulsive seizures.

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.

Generalised convulsive status epilepticus: an overview

Generalised convulsive status epilepticus is one of the most common emergencies encountered in clinical practice. This review discusses the recent understanding of this life-threatening condition with reference to the definition, pathophysiology, evaluation, complications, refractory status and prognosis. Besides epilepsy, other neurological and medical illnesses could be associated with status epilepticus. The goals of management and pharmacological approach are outlined, considering the available evidence. Prompt recognition and timely intervention, including pre-hospital treatment, are therapeutically beneficial. Refractory status should be managed in intensive care units under close monitoring. More evidence is needed for evolving the optimal treatment. A suitable treatment protocol would guide in avoiding the pitfalls at various points along the management pathway.

The approach to patients with "non-epileptic seizures"

Up to one fifth of patients who present to specialist clinics with seizures do not have epilepsy. The majority of such patients suffer from psychologically mediated episodes; dissociative seizures, often referred to as "non-epileptic seizures". This paper describes the diagnostic evaluation of seizure disorders, including clinical assessment and the role of special investigations. The organic and psychiatric imitators of epilepsy are outlined and findings on psychiatric assessment are reviewed. This group of patients often proves difficult to engage in appropriate treatment and an approach to explaining the diagnosis is described. As yet there are no controlled trials of treatment in this disorder but preliminary evidence suggests cognitive behavioural therapy is both a rational and promising way forward.

Status epilepticus: an evidence based guide

Writing this article enabled Matthew Walker to revisit the few randomised controlled trials of status epilepticus. This confirmed how poor the data are and that there is little evidence to support one treatment regimen over another

Wood's lamp employed as a provocative technique to identify pseudoseizures

We present a case of a 12-year-old female who presented to the emergency department with ictal phenomena suggestive of pseudoseizures. A Wood's lamp was successfully employed to induce the stereotypic phenomena and thereby identify the ictal events as nonepileptiform. Use of the Wood's lamp has not previously been reported as a provocative stimulus to induce pseudoseizures. Given its noninvasive nature and ready availability, the Wood's lamp should be considered for identification of pseudoseizures.

Ketamine for refractory status epilepticus: a case of possible ketamine-induced neurotoxicity

A 44-year-old man with treated neurosyphilis presented with subclinical status epilepticus (SE) refractory to intravenous high-dose lorazepam, phenytoin, and valproic acid over 4 days. Ketamine infusion was instituted after low-dose propofol sedation with gradual control of electrographic seizures over 72h. Reevaluation 3 months later revealed diffuse cerebellar and worsened cerebral atrophy, consistent with animal models of N-methyl-D-aspartate antagonist-mediated neurotoxicity. Animal studies of prolonged ketamine therapy are required before widespread human use in SE.

Progress in clinical neurosciences: Status epilepticus: a critical review of management options

Although generalized tonic-clonic status epilepticus (SE) is frequently seen, an evidence-based approach to management is limited by a lack of randomized clinical studies. Clinical practice, therefore, relies on a combination of expert recommendations, local hospital guidelines and dogma based on individual preference and past successes. This review explores selected and controversial aspects of SE in adults and provides a critical appraisal of currently recommended management strategies.

Status epilepticus

Status epilepticus is a medical emergency that requires rapid and vigorous treatment to prevent neuronal damage and systemic complications. Failure to diagnose and treat status epilepticus accurately and effectively results in significant morbidity and mortality. Cerebral metabolic decompensation occurs after approximately 30 min of uncontrolled convulsive activity, and the window for treatment is therefore limited. Therapy should proceed simultaneously on four fronts: termination of seizures; prevention of seizure recurrence once status is controlled; management of precipitating causes of status epilepticus; management of the complications. This article reviews current opinions about the classification, aetiology and pathophysiology of adult generalised convulsive status epilepticus and details practical management strategies for treatment of this life-threatening condition.

Treatment of status epilepticus

The approach to treatment of status epilepticus has changed because of the demonstration of decreased mortality with rapid intervention, completion of a randomized, double-blind VA Cooperative study comparing first-line agents, and further understanding of the pathophysiologic changes discovered in experimental animal studies. This article reviews the treatments of generalized convulsive status epilepticus in the prehospital, emergency department, and intensive care unit settings.

Pediatric status epilepticus: a perspective from Saudi Arabia

The purpose of this study was to assess risk factors and management of status epilepticus and non-status epilepticus seizures at a community hospital in Saudi Arabia. The research design was a prevalence study of a convenience sample of pediatric seizure episodes admitted to a 350-bed hospital from 1992 to 1997. The mean age at presentation was 2 years, 10 months, 43% of patients had no history of seizures, and 17% were transferred from other hospitals. Fifty-nine (28%) of 212 seizure episodes were status epilepticus (SE). These SE episodes were significantly more likely than non-SE episodes to be associated with a history of seizures, prior antiepileptic drug (AED) therapy, the presence of an acute etiology, and prolonged duration of seizures before hospitalization. SE episodes were also significantly more likely than non-SE episodes to receive an inappropriate AED, to require intensive care unit admission, to suffer morbidity, and to have SE recurrence at follow-up; however, the difference in mortality was not significant. In conclusion, children with SE were more likely than those with non-SE seizures to have a history of seizures and acute brain insults, prolonged seizure duration before hospitalization, and less optimal management and outcomes. Management of SE in this referral population can be improved by more rapid access to appropriate medical care.

Status epilepticus: new concepts

Generalized convulsive status epilepticus is a neurological emergency characterized by abnormally prolonged seizures. This review emphasizes recent developments that bear on our understanding of the pathophysiology and management of status epilepticus. Topics include GABAA receptor modulation during prolonged seizures, the role of genetics in susceptibility to status epilepticus, neuron-specific enolas, the Veterans Administration Cooperative Study Group trial comparison of various drug regimens, utility of the electroencephalogram in patient monitoring, emerging drug therapies and patient management in out-of-hospital settings.

Role of propofol in refractory status epilepticus

OBJECTIVE

To provide a review of the proposed mechanism of action, clinical efficacy, adverse effects, and therapeutic considerations associated with the use of propofol in the management of patients with refractory status epilepticus.

DATA SOURCES

A MEDLINE database (January 1966-April 1998) was searched for literature pertaining to status epilepticus and propofol. Additional literature was obtained from the references of selected articles identified in the search. Information from all articles published in English was considered for inclusion in the article.

DATA SYNTHESIS

Propofol is a unique, nonbarbiturate, anesthetic agent possessing anticonvulsant properties, although the exact anticonvulsant mechanism is unknown. Several case reports and two small, open, uncontrolled studies have described the efficacy of propofol in refractory status epilepticus. Most of these clinical reports discuss the utility of propofol after traditional treatment regimens have failed or are not tolerated. Initiation of propofol usually resulted in termination of seizure activity and/or electroencephalographic burst suppression within seconds that was sustained during the drug's use. Additionally, propofol was well tolerated. Advantages of propofol compared with traditional barbiturate anesthetic agents include better cardiovascular tolerability and a more favorable pharmacokinetic profile, allowing for rapid assessment of efficacy and neurologic assessment upon drug withdrawal. Propofol has been associated with a variety of neuroexcitatory adverse events such as opisthotonos, muscle rigidity, and choreoathetoid movements. Additionally, although the data are inconclusive, propofol has also been reported to cause seizures.

CONCLUSIONS

Propofol has shown promising results in the management of refractory status epilepticus when traditional therapies have failed or were not tolerated; however, controlled clinical trials are needed to better assess the comparative efficacy, neurologic adverse effects, and clinical outcome to better define its role in refractory status epilepticus.

The epidemiology and management of status epilepticus

Status epilepticus refers to a prolonged seizure state, usually taken as lasting 30 min or longer. This review considers recent studies of the epidemiology of status epilepticus; these have confirmed the high incidence and the high associated mortality and morbidity. Advances in the management of status epilepticus are also reviewed but despite these advances there is still a lack of good comparative studies on which to base treatment regimens.