Second-line status epilepticus treatment: comparison of phenytoin, valproate, and levetiracetam

Clonazepam Loading Dose in Status Epilepticus: Is More Always Better?

BACKGROUND AND OBJECTIVES

Benzodiazepines are the first treatment line in status epilepticus (SE). Despite their well-established benefit, benzodiazepines are frequently underdosed with potential detrimental consequences. In some European countries, clonazepam (CLZ) is commonly used as the first line treatment. The aim of this study was to explore the correlation between CLZ loading doses and SE outcome.

METHODS

This study included a retrospective analysis of a prospective registry in Lausanne, Switzerland (CHUV Lausanne University Hospital), including all SE episodes treated between February 2016 and February 2021. Only adults (> 16 years old) were included with CLZ used as the first treatment line. Post-anoxic SE were excluded because of significant differences in physiopathology and prognosis. Patient characteristics, SE features, the validated SE severity score (STESS), and treatment characteristics were prospectively recorded. We considered loading doses of 0.015 mg/kg or higher (following commonly recommended loading doses) as high doses. We analyzed outcome in terms of number of treatment lines after the CLZ, proportion of refractory episodes, intubation for airways protection, intubation for SE treatment, and mortality. We performed univariable analyses to investigate the association between loading doses and clinical response. A multivariable stepwise backward binary logistic regression was applied for adjusting for potential confounders. Multivariable linear regression was similarly used to analyze CLZ dose as a continuous variable.

RESULTS

We collected 251 SE episodes in 225 adult patients. Median CLZ loading dose was 0.010 mg/kg. CLZ high doses were used in 21.9% of SE episodes (in 43.8% for > 80% of the high dose). Thirteen percent of patients with SE were intubated for airways control, while intubation was needed in 12.7% for SE treatment. High CLZ loading doses were independently associated with younger age (median 62 versus 68 years old, p = 0.002), lesser weight (65 kg versus 75 kg, p = 0.001) and more frequent intubation for airways protection (23% vs 11%, p = 0.013), but differing CLZ dose was not associated with any outcome parameter.

CONCLUSION

CLZ high doses were more frequently used for SE treatment in younger patients with healthy weight and were more often associated with intubation for airways protection, probably as an adverse event. Varying CLZ dose did not alter outcome in SE, raising the possibility that commonly recommended doses are above what is needed, at least in some patients. Our results suggest that CLZ doses in SE may be individualized depending on the clinical setting.

Treatment of benzodiazepine-refractory status epilepticus: A retrospective, cohort study

INTRODUCTION

Status epilepticus (SE) is a frequent neurological emergency, derived from the failure of mechanisms responsible for seizure termination. The present study aims to compare the efficacy of the most common antiseizure medications (ASMs) employed for the treatment of benzodiazepine-refractory SE.

METHODS

We performed a retrospective cohort study of all SE episodes treated in our hospital between January 2016 and December 2020. Inclusion criteria were: age ≥ 18 years; a diagnosis of status epilepticus. Exclusion criteria were: status epilepticus resolved by initial therapy with benzodiazepines; impossibility to retrieve medical records. We considered as effective the ASM that was the last drug introduced or increased in dose before termination of SE and without changes in the co-medication.

RESULTS

A total of 244 episodes in 219 patients were included in the study. The mean age of the final study cohort was 63.6 ± 19.2, with 108 (49%) men. In the total cohort, phenytoin (PHT) showed the highest response rate (57.6%), followed by lacosamide (LCM) (40.7%) and valproate (VPA) (39.8%). The comparative efficacy among the different drugs was significantly different (p < 0.001). In the pairwise comparisons, VPA was superior to levetiracetam (LEV) (response rate: 39.75% vs 24.71%; p = 0.004), but not to LCM. Phenytoin had a significantly higher resolution rate compared to VPA (response rate: 57.63% vs 39.75%; p = 0.02) and LEV (response rate: 57.63% vs 24.71; p < 0.001). The clinical predictors of anaesthetics administration were a disorder of consciousness upon clinical presentation, previous diagnosis of epilepsy, and younger age.

CONCLUSION

In our cohort of SE, PHT showed higher effectiveness in terminating established SE, as well as refractory SE in the subgroup of patients treated with anaesthetics.

Optimizing Status Epilepticus Management in the Emergency Department: It's About Time

Status epilepticus (SE) is a frequent medical emergency that requires expedited treatment to avoid the ensuing high incidence of morbidity and mortality associated with prolonged seizures. Protracted seizure duration itself has the potential to result in maladaptive neuronal responses that can not only further increase seizure duration and worsen clinical outcomes but also lead to reduced responsiveness to pharmacotherapy. Benzodiazepines are consistently recommended as first-line treatment due to their rapid onset and efficacy in terminating seizures, followed by the emergent administration of an antiepileptic drug (AED). Various benzodiazepine and AED options are recommended and can be utilized in this setting, all with their own unique advantages and challenges. With time at a premium, agents should be selected that can be rapidly administered and have an advantageous pharmacokinetic profile in order to limit seizure duration and optimize outcomes. The intent of this review is to provide an outline of the importance of time-to-treatment implementation in this setting, assess the landscape of options that may provide timing advantages, and examine potential strategies for deploying expeditious therapy.

Does diabetes mellitus affect the safety profile of valproic acid for the treatment of status epilepticus? A retrospective cohort study

Background

In the treatment of status epilepticus less is known about the influence of comorbidities on the safety profile of anticonvulsive drugs. Especially patients with diabetes mellitus may be predisposed to certain adverse events that have been related to therapy with valproic acid. In this single-center retrospective cohort study we examined if the complications of the intravenous treatment with valproic acid is different in patients with or without diabetes.

Methods

Patients who were treated for status epilepticus with intravenous valproic acid between 2008 and 2020 were identified. Primary endpoint was the discontinuation of therapy with valproic acid due to adverse events. Relevant secondary endpoints were the functional status at the time of discharge from hospital in comparison to the premorbid state and the in-hospital mortality. Both groups (patients with or without diabetes) were compared by Mann–Whitney U-Test or Pearson´s Chi² test. To identify therapy with valproic acid as a risk factor of in-hospital mortality, a binary regression model was used.

Results

During the study period 408 patients and 482 episodes of status epilepticus were treated with intravenous valproic acid. Group comparisons did not reveal a significant difference in the rates of discontinuation of therapy. A difference was found in the rate of thrombocytopenia (p = 0.015), which occurred more often in patients with diabetes. In total, 36 hypoglycemic episodes could be identified, two occurred spontaneously under intravenous valproic acid. After correction for potential confounders, continuous therapy with valproic acid could not be confirmed as an independent risk factor for in-hospital mortality (p = 0.079). In patients with diabetes, the proportion of patients with a good functional state, indicated by the modified Rankin Scale, was significantly lower in both times (premorbid: 55% vs. 69%, p = 0.008; at discharge: 22% vs. 36%, p = 0.004).

Conclusions

Tolerability of the treatment with valproic acid was similar in patients with or without diabetes. Diabetes as a relevant comorbidity can signal a potentially increased risk of a poor outcome after status epilepticus.

Trial registration: The study was registered at the German Clinical Trials Register on 8 April 2022 (DRKS 00,027,836).

Supplementary Information

The online version contains supplementary material available at 10.1186/s42466-022-00212-w.

Nose to Brain Delivery of Phenytoin Sodium Loaded Nano Lipid Carriers: Formulation, Drug Release, Permeation and In Vivo Pharmacokinetic Studies

An acute epileptic seizure is a seizure emergency fatal condition that requires immediate medical attention. IV phenytoin sodium remains the second line therapeutic agent for the immediate treatment of status epilepticus. Phenytoin sodium formulated as nanolipid carriers (NLCs) seems to be promising as an intranasal delivery system for controlling acute seizures. Three different nanosized phenytoin sodium loaded NLCs (<50 nm, 50-100 nm and >100 nm) were prepared by melt emulsification and was further characterised. In vitro drug release studies showed immediate drug release from phenytoin sodium loaded NLCs of <50 nm size, which is highly essential for acute seizure control. The ex vivo permeation study indicated greater permeation from <50 nm sized NLC through the olfactory epithelium compared to thecontrol drug solution. Invivo pharmacokinetic studies revealed higher drug concentration in CSF/brain within 5 min upon intranasal administration of <50 nm sized phenytoin sodium NLCs than the control drug solution and marketed IV phenytoin sodium, indicating direct and rapid nose to brain drug transport through the olfactory epithelium. The study has shown that formulation strategies can enhance olfactory uptake, and phenytoin sodium NLCs of desired particle sizes (<50 nm) offer promising potential for nose to brain direct delivery of phenytoin sodium in treating acute epileptic seizures.

Early Exposure of Fosphenytoin, Levetiracetam, and Valproic Acid After High-Dose Intravenous Administration in Young Children With Benzodiazepine-Refractory Status Epilepticus

Fosphenytoin (FOS) and its active form, phenytoin (PHT), levetiracetam (LEV), and valproic acid (VPA) are commonly used second-line treatments of status epilepticus. However, limited information is available regarding LEV and VPA concentrations following high intravenous doses, particularly in young children. The Established Status Epilepticus Treatment Trial, a blinded, comparative effectiveness study of FOS, LEV, and VPA for benzodiazepine-refractory status epilepticus provided an opportunity to investigate early drug concentrations. Patients aged ≥2 years who continued to seizure despite receiving adequate doses of benzodiazepines were randomly assigned to FOS, LEV, or VPA infused over 10 minutes. A sparse blood-sampling approach was used, with up to 2 samples collected per patient within 2 hours following drug administration. The objective of this work was to report early drug exposure of PHT, LEV, and VPA and plasma protein binding of PHT and VPA. Twenty-seven children with median (interquartile range) age of 4 (2.5-6.5) years were enrolled. The total plasma concentrations ranged from 69 to 151.3 μg/mL for LEV, 11.3 to 26.7 μg/mL for PHT and 126 to 223 μg/mL for VPA. Free fraction ranged from 4% to 19% for PHT and 17% to 51% for VPA. This is the first report in young children of LEV concentrations with convulsive status epilepticus as well as VPA concentrations after a 40 mg/kg dose. Several challenges limited patient enrollment and blood sampling. Additional studies with a larger sample size are required to evaluate the exposure-response relationships in this emergent condition.

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

BACKGROUND

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

METHODS

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

DISCUSSION

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

TRIAL REGISTRATION

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

Levetiracetam versus Phenytoin for the Pharmacotherapy of Benzodiazepine-Refractory Status Epilepticus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Recent studies have shown conflicting results regarding the effectiveness of levetiracetam for treating benzodiazepine-refractory status epilepticus (SE) compared with phenytoin. Therefore, a meta-analysis was carried out to assess the value of levetiracetam versus phenytoin in the pharmacotherapy of benzodiazepine-refractory SE.

OBJECTIVE

The aim of this systematic review and meta-analysis was to compare the efficacy and safety of levetiracetam and phenytoin in the treatment of benzodiazepine-refractory SE.

METHODS

The MEDLINE, EMBASE, CENTRAL and ClinicalTrials.gov databases were searched for randomized controlled trials (RCTs) that had been conducted to evaluate levetiracetam versus phenytoin for benzodiazepine-refractory SE, to April 2020. The data were assessed using Review Manager 5.3 software. The risk ratio (RR) was analyzed using dichotomous outcomes, and calculated using a random-effect model.

RESULTS

We pooled 1850 patients from 12 RCTs. Patients in the levetiracetam group had a significantly higher rate of clinical seizure cessation than in the phenytoin group (75.2% vs. 67.8%; RR 1.14, 95% confidence interval [CI] 1.05-1.25, p = 0.003). Moreover, less adverse events were observed in the levetiracetam group than in the phenytoin group (17.8% vs. 21.4%; RR 0.82, 95% CI 0.70-0.97, p = 0.02). In subgroup analysis, clinical seizure cessation was achieved more frequently with a higher dose of levetiracetam (> 30 mg/kg) [RR 1.15, 95% CI 1.00-1.32, p = 0.05]. Furthermore, in the subgroup of children, levetiracetam showed a higher rate of clinical seizure cessation than phenytoin (RR 1.13, 95% CI 1.02-1.25, p = 0.02).

CONCLUSION

Pharmacotherapy for BZD-refractory SE by LEV is superior to PHT in efficacy and safety outcomes.

Status Epilepticus-Work-Up and Management in Children

Status epilepticus (SE) is one of the most common neurological emergencies in children and has a mortality of 2 to 4%. Admissions for SE are very resource-consuming, especially in refractory and super-refractory SE. An increasing understanding of the pathophysiology of SE leaves room for improving SE treatment protocols, including medication choice and timing. Selecting the most efficacious medications and giving them in a timely manner may improve outcomes. Benzodiazepines are commonly used as first line and they can be used in the prehospital setting, where most SE episodes begin. The diagnostic work-up should start simultaneously to initial treatment, or as soon as possible, to detect potentially treatable causes of SE. Although most etiologies are recognized after the first evaluation, the detection of more unusual causes may become challenging in selected cases. SE is a life-threatening medical emergency in which prompt and efficacious treatment may improve outcomes. We provide a summary of existing evidence to guide clinical decisions regarding the work-up and treatment of SE in pediatric patients.

Management of epileptic disorders using nanotechnology-based strategies for nose-to-brain drug delivery

INTRODUCTION

Epilepsy, a major neurological disorder affects about 1% of the Indian population. The discovery of noninvasive strategies for epilepsy presents a challenge for the scientists. Different types of nose-to-brain dosage-forms have been studied for epilepsy management. It aims to give new perspectives for developing new and existing anti-epileptic drugs. Combining nanotechnology with nose-to-brain approach can help in promoting the treatment efficacy by site-specific delivery. Also, it will minimize the side-effects and patient noncompliance observed in conventional administration routes. Peptide delivery can be an interesting approach for the management of epilepsy. Drug-loaded intranasal nanoformulations exhibit diverse prospective potentials in the management of epilepsy. Considering that, nanotherapy using nose-to-brain delivery as a prospective technique for the efficient management of epilepsy is reviewed.

AREAS COVERED

The authors have compiled all recently available data pertaining to the nose-to-brain delivery of therapeutics using nanotechnological strategies. The fundamental mechanism of nose-to-brain delivery, claims for intranasal delivery and medical devices for epilepsy are discussed.

EXPERT OPINION

Drug-loaded intranasal nanoformulations exhibit different prospective potentials in the management of epilepsy. Considering the foregoing research done in the field of nanotechnology, globally, authors propose nose-to-brain delivery of nanoformulations as a potential technique for the efficient management of epilepsy.

Drug Trials in Status Epilepticus: Current Evidence and Future Concepts

Status epilepticus (SE) is a neurologic emergency with high morbidity and mortality. After many advances in the field, several unanswered questions remain for optimal treatment after the early stage of SE. This narrative review describes some of the important drug trials for SE treatment that have shaped the understanding of the treatment of SE. The authors also propose possible clinical trial designs for the later stages of SE that may allow assessment of currently available and new treatment options. Status epilepticus can be divided into four stages for treatment purposes: early, established, refractory, and superrefractory. Ongoing convulsive seizures for more than 5 minutes or nonconvulsive seizure activity for more than 10 to 30 minutes is considered early SE. Failure to control the seizure with first-line treatment (usually benzodiazepines) is defined as established SE. If SE continues despite treatment with an antiseizure medicine, it is considered refractory SE, which is usually treated with additional antiseizure medicines or intravenous anesthetic agents. Continued seizures for more than 24 hours despite use of intravenous anesthetic agents is termed superrefractory SE. Evidence-based treatment recommendations from high-quality clinical trials are available for only the early stages of SE. Among the challenges for designing a treatment trial for the later stages SE is the heterogeneity of semiology, etiology, age groups, and EEG correlates. In many instances, SE is nonconvulsive in later stages and diagnosis is possible only with EEG. EEG patterns can be challenging to interpret and only recently have consensus criteria for EEG diagnosis of SE emerged. Despite having these EEG criteria, interrater agreement in EEG interpretation can be challenging. Defining successful treatment can also be difficult. Finally, the ethics of randomizing treatment and possibly using a placebo in critically ill patients must also be considered. Despite these challenges, clinical trials can be designed that navigate these issues and provide useful answers for how best to treat SE at various stages.

Treatment of Refractory Convulsive Status Epilepticus: A Comprehensive Review by the American Epilepsy Society Treatments Committee

Purpose:

Established tonic–clonic status epilepticus (SE) does not stop in one-third of patients when treated with an intravenous (IV) benzodiazepine bolus followed by a loading dose of a second antiseizure medication (ASM). These patients have refractory status epilepticus (RSE) and a high risk of morbidity and death. For patients with convulsive refractory status epilepticus (CRSE), we sought to determine the strength of evidence for 8 parenteral ASMs used as third-line treatment in stopping clinical CRSE.

Methods:

A structured literature search (MEDLINE, Embase, CENTRAL, CINAHL) was performed to identify original studies on the treatment of CRSE in children and adults using IV brivaracetam, ketamine, lacosamide, levetiracetam (LEV), midazolam (MDZ), pentobarbital (PTB; and thiopental), propofol (PRO), and valproic acid (VPA). Adrenocorticotropic hormone (ACTH), corticosteroids, intravenous immunoglobulin (IVIg), magnesium sulfate, and pyridoxine were added to determine the effectiveness in treating hard-to-control seizures in special circumstances. Studies were evaluated by predefined criteria and were classified by strength of evidence in stopping clinical CRSE (either as the last ASM added or compared to another ASM) according to the 2017 American Academy of Neurology process.

Results:

No studies exist on the use of ACTH, corticosteroids, or IVIg for the treatment of CRSE. Small series and case reports exist on the use of these agents in the treatment of RSE of suspected immune etiology, severe epileptic encephalopathies, and rare epilepsy syndromes. For adults with CRSE, insufficient evidence exists on the effectiveness of brivaracetam (level U; 4 class IV studies). For children and adults with CRSE, insufficient evidence exists on the effectiveness of ketamine (level U; 25 class IV studies). For children and adults with CRSE, it is possible that lacosamide is effective at stopping RSE (level C; 2 class III, 14 class IV studies). For children with CRSE, insufficient evidence exists that LEV and VPA are equally effective (level U, 1 class III study). For adults with CRSE, insufficient evidence exists to support the effectiveness of LEV (level U; 2 class IV studies). Magnesium sulfate may be effective in the treatment of eclampsia, but there are only case reports of its use for CRSE. For children with CRSE, insufficient evidence exists to support either that MDZ and diazepam infusions are equally effective (level U; 1 class III study) or that MDZ infusion and PTB are equally effective (level U; 1 class III study). For adults with CRSE, insufficient evidence exists to support either that MDZ infusion and PRO are equally effective (level U; 1 class III study) or that low-dose and high-dose MDZ infusions are equally effective (level U; 1 class III study). For children and adults with CRSE, insufficient evidence exists to support that MDZ is effective as the last drug added (level U; 29 class IV studies). For adults with CRSE, insufficient evidence exists to support that PTB and PRO are equally effective (level U; 1 class III study). For adults and children with CRSE, insufficient evidence exists to support that PTB is effective as the last ASM added (level U; 42 class IV studies). For CRSE, insufficient evidence exists to support that PRO is effective as the last ASM used (level U; 26 class IV studies). No pediatric-only studies exist on the use of PRO for CRSE, and many guidelines do not recommend its use in children aged <16 years. Pyridoxine-dependent and pyridoxine-responsive epilepsies should be considered in children presenting between birth and age 3 years with refractory seizures and no imaging lesion or other acquired cause of seizures. For children with CRSE, insufficient evidence exists that VPA and diazepam infusion are equally effective (level U, 1 class III study). No class I to III studies have been reported in adults treated with VPA for CRSE. In comparison, for children and adults with established convulsive SE (ie, not RSE), after an initial benzodiazepine, it is likely that loading doses of LEV 60 mg/kg, VPA 40 mg/kg, and fosphenytoin 20 mg PE/kg are equally effective at stopping SE (level B, 1 class I study).

Conclusions:

Mostly insufficient evidence exists on the efficacy of stopping clinical CRSE using brivaracetam, lacosamide, LEV, valproate, ketamine, MDZ, PTB, and PRO either as the last ASM or compared to others of these drugs. Adrenocorticotropic hormone, IVIg, corticosteroids, magnesium sulfate, and pyridoxine have been used in special situations but have not been studied for CRSE. For the treatment of established convulsive SE (ie, not RSE), LEV, VPA, and fosphenytoin are likely equally effective, but whether this is also true for CRSE is unknown. Triple-masked, randomized controlled trials are needed to compare the effectiveness of parenteral anesthetizing and nonanesthetizing ASMs in the treatment of CRSE.

Critical Care Management of Status Epilepticus at a Tertiary Care University Hospital

BACKGROUND

Status epilepticus (SE) is a neurological emergency associated with significant morbidity and mortality. The objective of this study was to review the critical care management of patients with SE focusing on antiepileptic drugs (AEDs) as well as to determine the optimal dosing strategies of phenytoin (PHT) and predictors of its effectiveness.

METHODS

A retrospective chart review of adult patients with SE admitted to the University of Alberta Hospital, Canada, was conducted.

RESULTS

Fifty-six admissions were included. Benzodiazepines (BDZs) were initially given in 89% of our patients. Following BDZs, PHT and levetiracetam were the most commonly initiated AEDs as first- and second-line agents and were deemed effective in 30/44 and 5/11 patients, respectively. Patients who received a PHT loading dose (LD) of 1000 mg were less likely to reach target levels compared with a weight-based LD ≥15 mg/kg (29% vs. 60%). Likewise, patients who received a maintenance dose (MD) of 300 mg/day were less likely to reach target compared with 400 mg/day or >5 mg/kg per day; however, this did not reach statistical significance. Three variables were found to be associated with PHT effectiveness: tonic-clonic SE (OR 5.01, 95% CI 1.02-24.7, p = 0.048), history of seizures and BMI <30 kg/m2 (OR 0.16, 95% CI 0.03-1.07, p = 0.059).

CONCLUSIONS

Further studies of the predictors of PHT effectiveness, specifically obesity, are necessary to help individualize care. Finally, we suggest that PHT should be loaded according to the guidelines as 20 mg/kg followed by an MD of at least 400 mg/day or >5 mg/kg per day.

Recommandations Formalisées d’Experts SRLF/SFMU : Prise en charge des états de mal épileptiques en préhospitalier, en structure d’urgence et en réanimation dans les 48 premières heures (A l’exclusion du nouveau-né et du nourrisson)

La Société de réanimation de langue française et la Société française de médecine d’urgence ont décidé d’élaborer de nouvelles recommandations sur la prise en charge de l’état mal épileptique (EME) avec l’ambition de répondre le plus possible aux nombreuses questions pratiques que soulèvent les EME : diagnostic, enquête étiologique, traitement non spécifique et spécifique. Vingt-cinq experts ont analysé la littérature scientifique et formulé des recommandations selon la méthodologie GRADE. Les experts se sont accordés sur 96 recommandations. Les recommandations avec le niveau de preuve le plus fort ne concernent que l’EME tonico-clonique généralisé (EMTCG) : l’usage des benzodiazépines en première ligne (clonazépam en intraveineux direct ou midazolam en intramusculaire) est recommandé, répété 5 min après la première injection (à l’exception du midazolam) en cas de persistance clinique. En cas de persistance 5 min après cette seconde injection, il est proposé d’administrer la seconde ligne thérapeutique : valproate de sodium, (fos-)phénytoïne, phénobarbital ou lévétiracétam. La persistance avérée de convulsions 30 min après le début de l’administration du traitement de deuxième ligne signe l’EMETCG réfractaire. Il est alors proposé de recourir à un coma thérapeutique au moyen d’un agent anesthésique intraveineux de type midazolam ou propofol. Des recommandations spécifiques à l’enfant et aux autres EME sont aussi énoncées.

Clinical outcomes and treatments effectiveness in status epilepticus resolved by antiepileptic drugs: A five-year observational study

Objective

To evaluate clinical outcomes and treatment effectiveness of status epilepticus finally resolved by nonbenzodiazepine antiepileptic drugs (AEDs).

Methods

All consecutive SE episodes observed from September 1, 2013, to September 1, 2018, and resolved by AEDs were considered. Diagnosis and classification of SE followed the 2015 ILAE proposal. Nonconvulsive status (NCSE) diagnosis was confirmed according to the Salzburg EEG criteria. The modified Rankin Scale and deaths at 30 days from onset were used to evaluate outcomes.

Results

A total of 277 status episodes (mean age 71 years; 61% female) were treated and resolved by antiepileptic drugs after 382 treatment trials. 68% of the SE resolved after AED use as first/second treatment line, while subsequent trials with AEDs gave an additional 32% resolution. A return to baseline conditions was observed in 48% of the patients, while overall mortality was 19% without significant changes across the study years. Mortality was higher in NCSE than in convulsive SE (22.5% vs 12.9%; P < .05), while mortality did not differ in SE episodes resolved by a first/second AED trial (17.2%) versus SE resolved by successive treatment trials (18.9%). The resolution rate of intravenous AEDs was 82% for valproate, 77% for lacosamide, 71% for phenytoin, and 62% for levetiracetam. No significant differences were found in head-to-head comparison, but for the valproate-levetiracetam one that was related to NCSE episodes in which valproate resulted to be effective in 86% of the trials while levetiracetam in 62% (P < .002).

Significance

A high short-term mortality, stable over time, was observed in SE despite resolution of seizures, especially in SE with nonconvulsive semiology. Comparative AED efficacy showed no significant differences except for higher resolution rate for valproate versus levetiracetam in NCSE.

Randomized Trial of Three Anticonvulsant Medications for Status Epilepticus

BACKGROUND

The choice of drugs for patients with status epilepticus that is refractory to treatment with benzodiazepines has not been thoroughly studied.

METHODS

In a randomized, blinded, adaptive trial, we compared the efficacy and safety of three intravenous anticonvulsive agents - levetiracetam, fosphenytoin, and valproate - in children and adults with convulsive status epilepticus that was unresponsive to treatment with benzodiazepines. The primary outcome was absence of clinically evident seizures and improvement in the level of consciousness by 60 minutes after the start of drug infusion, without additional anticonvulsant medication. The posterior probabilities that each drug was the most or least effective were calculated. Safety outcomes included life-threatening hypotension or cardiac arrhythmia, endotracheal intubation, seizure recurrence, and death.

RESULTS

A total of 384 patients were enrolled and randomly assigned to receive levetiracetam (145 patients), fosphenytoin (118), or valproate (121). Reenrollment of patients with a second episode of status epilepticus accounted for 16 additional instances of randomization. In accordance with a prespecified stopping rule for futility of finding one drug to be superior or inferior, a planned interim analysis led to the trial being stopped. Of the enrolled patients, 10% were determined to have had psychogenic seizures. The primary outcome of cessation of status epilepticus and improvement in the level of consciousness at 60 minutes occurred in 68 patients assigned to levetiracetam (47%; 95% credible interval, 39 to 55), 53 patients assigned to fosphenytoin (45%; 95% credible interval, 36 to 54), and 56 patients assigned to valproate (46%; 95% credible interval, 38 to 55). The posterior probability that each drug was the most effective was 0.41, 0.24, and 0.35, respectively. Numerically more episodes of hypotension and intubation occurred in the fosphenytoin group and more deaths occurred in the levetiracetam group than in the other groups, but these differences were not significant.

CONCLUSIONS

In the context of benzodiazepine-refractory convulsive status epilepticus, the anticonvulsant drugs levetiracetam, fosphenytoin, and valproate each led to seizure cessation and improved alertness by 60 minutes in approximately half the patients, and the three drugs were associated with similar incidences of adverse events. (Funded by the National Institute of Neurological Disorders and Stroke; ESETT ClinicalTrials.gov number, NCT01960075.).

Randomized trial of lacosamide versus fosphenytoin for nonconvulsive seizures

OBJECTIVE

The optimal treatment of nonconvulsive seizures in critically ill patients is uncertain. We evaluated the comparative effectiveness of the antiseizure drugs lacosamide (LCM) and fosphenytoin (fPHT) in this population.

METHODS

The TRENdS (Treatment of Recurrent Electrographic Nonconvulsive Seizures) study was a noninferiority, prospective, multicenter, randomized treatment trial of patients diagnosed with nonconvulsive seizures (NCSs) by continuous electroencephalography (cEEG). Treatment was randomized to intravenous (IV) LCM 400mg or IV fPHT 20mg phenytoin equivalents/kg. The primary endpoint was absence of electrographic seizures for 24 hours as determined by 1 blinded EEG reviewer. The frequency with which NCS control was achieved in each arm was compared, and the 90% confidence interval (CI) was determined. Noninferiority of LCM to fPHT was to be concluded if the lower bound of the CI for relative risk was >0.8.

RESULTS

Seventy-four subjects were enrolled (37 LCM, 37 fPHT) between August 21, 2012 and December 20, 2013. The mean age was 63.6 years; 38 were women. Seizures were controlled in 19 of 30 (63.3%) subjects in the LCM arm and 16 of 32 (50%) subjects in the fPHT arm. LCM was noninferior to fPHT (p = 0.02), with a risk ratio of 1.27 (90% CI = 0.88-1.83). Treatment emergent adverse events (TEAEs) were similar in both arms, occurring in 9 of 35 (25.7%) LCM and 9 of 37 (24.3%) fPHT subjects (p = 1.0).

INTERPRETATION

LCM was noninferior to fPHT in controlling NCS, and TEAEs were comparable. LCM can be considered an alternative to fPHT in the treatment of NCSs detected on cEEG. Ann Neurol 2018;83:1174-1185.

Meta-analysis and cost-effectiveness of second-line antiepileptic drugs for status epilepticus

Objective

Compare the cost and effectiveness of nonbenzodiazepine antiepileptic drugs (non-BZD AEDs) for treatment of BZD-resistant convulsive status epilepticus (SE).

Methods

Decision analysis model populated with effectiveness data from a systematic review and meta-analysis of the literature, and cost data from publicly available prices. The primary outcome was cost per seizure stopped ($/SS). Sensitivity analyses evaluated the robustness of the results across a wide variation of the input parameters.

Results

We included 24 studies with 1,185 SE episodes. The most effective non-BZD AED was phenobarbital (PB) with a probability of SS of 0.8 (95% confidence interval [CI]: 0.69–0.88), followed by valproate (VPA) (0.71 [95% CI: 0.61–0.79]), lacosamide (0.66 [95% CI: 0.51–0.79]), levetiracetam (LEV) (0.62 [95% CI: 0.5–0.73]), and phenytoin/fosphenytoin (PHT) (0.53 [95% CI: 0.39–0.67]). In pairwise comparisons, PB was more effective than PHT (p = 0.002), VPA was more effective than PHT (p = 0.043), and PB was more effective than LEV (p = 0.018). The most cost-effective non-BZD AED was LEV (incremental cost-effectiveness ratio [ICER]: $18.55/SS), followed by VPA (ICER: $94.44/SS), and lastly PB (ICER: $847.22/SS). PHT and lacosamide were not cost-effective compared to the other options. Sensitivity analyses showed marked overlap in cost-effectiveness, but PHT was consistently less cost-effective than LEV, VPA, and PB.

Conclusion

VPA and PB were more effective than PHT for SE. There is substantial overlap in the cost-effectiveness of non-BZD AEDs for SE, but available evidence does not support the preeminence of PHT, neither in terms of effectiveness nor in terms of cost-effectiveness.

Focal status epilepticus: a review of pharmacological treatment

INTRODUCTION

Status epilepticus (SE) is a neurological emergency associated with high morbidity and mortality. One prognostic factor is the type of SE. The purpose of this review is to analyse the most recent recommendations of different scientific societies and expert groups on the treatment of SE, and the latest studies, to assess the literature on the management of focal SE.

METHODS

We searched PubMed for studies published between 1 August 2008 and 1 August 2018 on the pharmacological treatment of focal SE and its different types in adults.

RESULTS

We identified 29 publications among reviews, treatment guidelines, meta-analyses, clinical trials, and case series on the treatment of SE. Only 3 of them accounted for whether SE was focal or generalised; 4 focused exclusively on focal SE, and 7 differentiated between convulsive and non-convulsive SE and also record the presence of focal seizures. Treatment recommendations for focal SE do not differ from those of generalised SE in stages I and II: initially intravenous lorazepam or diazepam, if the intravenous route is available, and otherwise intramuscular midazolam, followed by intravenous phenytoin, valproate, levetiracetam, or lacosamide if seizures persist. Use of anaesthetic drugs should be delayed for as long as possible in patients with refractory focal SE.

CONCLUSIONS

The available scientific evidence is insufficient to claim that pharmacological treatment of focal SE should be different from treatment for generalised SE. More studies with a greater number of patients are needed.

Factors predicting cessation of status epilepticus in clinical practice: Data from a prospective observational registry (SENSE)

OBJECTIVE

To investigate the initial termination rate of status epilepticus (SE) in a large observational study and explore associated variables.

METHODS

Data of adults treated for SE were collected prospectively in centers in Germany, Austria, and Switzerland, during 4.5 years. Incident episodes of 1,049 patients were analyzed using uni- and multivariate statistics to determine factors predicting cessation of SE within 1 hour (for generalized convulsive SE [GCSE]) and 12 hours (for non-GCSE) of initiating treatment.

RESULTS

Median age at SE onset was 70 years; most frequent etiologies were remote (32%) and acute (31%). GCSE was documented in 43%. Median latency between SE onset and first treatment was 30 minutes in GCSE and 150 minutes in non-GCSE. The first intravenous compound was a benzodiazepine in 86% in GCSE and 73% in non-GCSE. Bolus doses of the first treatment step were lower than recommended by current guidelines in 76% of GCSE patients and 78% of non-GCSE patients. In 319 GCSE patients (70%), SE was ongoing 1 hour after initiating treatment and in 342 non-GCSE patients (58%) 12 hours after initiating treatment. Multivariate Cox regression demonstrated that use of benzodiazepines as first treatment step and a higher cumulative dose of anticonvulsants within the first period of treatment were associated with shorter time to cessation of SE for both groups.

INTERPRETATION

In clinical practice, treatment guidelines were not followed in a substantial proportion of patients. This underdosing correlated with lack of cessation of SE. Our data suggest that sufficiently dosed benzodiazepines should be used as a first treatment step. ANN NEUROL 2019;85:421-432.

Clinical Efficacy and Safety of Injectable Levetiracetam Versus Phenytoin as Second-Line Therapy in the Management of Generalized Convulsive Status Epilepticus in Children: An Open-Label Randomized Controlled Trial

Background and Purpose

There is sparsity of quality evidence for the use of drugs after first-line benzodiazepines in convulsive status epilepticus in children. The aim of the study was to compare the clinical efficacy and safety of intravenous levetiracetam versus intravenous phenytoin as second-line drugs in the management of generalized convulsive status epilepticus in children.

Methods

This open-label randomized controlled trial was conducted in the Emergency Department of The Children's Hospital and The Institute of Child Health, Multan, Pakistan over a period of 4 years and 6 months from January 2014 to June 2018. This study included 600 children with generalized convulsive status epilepticus: 300 in the 40 mg/kg levetiracetam group, and 300 in the 20 mg/kg phenytoin group. Cessation of a clinical seizure (seizure cessation rate) within 30 minutes after the end of drug administration was the primary outcome in this study, and the presence or absence of adverse effects was noted as the secondary outcome. Data were analyzed using SPSS (version 20.0).

Results

The children in the levetiracetam and phenytoin were aged 3.5±0.2 and 3.4±0.2 years (mean±SD), respectively, their seizure durations before the start of treatment were 25.1±0.6 and 23.8±0.4 minutes, and their treatment efficacies were 278/300 (92.7%) and 259/300 (83.3%). Levetiracetam was significantly more effective than phenytoin (p=0.012), with no significant difference in safety. Adverse events were observed in eight children in the phenytoin group.

Conclusions

Levetiracetam is significantly more effective than phenytoin for the treatment of convulsive status epilepticus in children who have failed to respond to benzodiazepines.

Evaluation of Intravenous Phenytoin and Fosphenytoin Loading Doses: Influence of Obesity and Sex

BACKGROUND

Recommended loading doses (LDs) of phenytoin and fosphenytoin range from 10 to 25 mg/kg. Few studies have examined the LD requirements in male versus female patients and in patients who are obese.

OBJECTIVES

To examine the influence of obesity and sex on phenytoin LDs.

METHODS

This was a retrospective cohort study comparing free phenytoin or fosphenytoin serum concentrations following LDs in male versus female and nonobese versus obese patients. An equation used for determining LDs in obese patients was evaluated.

RESULTS

There were 141 nonobese and 54 obese patients. When adjusted for total body weight, the obese cohort received a smaller LD than the nonobese cohort (17 mg/kg, interquartile range [IQR] = 14.9-20.0, vs 20 mg/kg, IQR = 18.6-20.0, respectively; P < 0.001). There was no difference between the 2 cohorts in the measured free phenytoin concentration following the LD (obese: 1.7 µg/mL [IQR = 1.4-2.0]; nonobese: 1.8 µg/mL [IQR = 1.5-2.1]; P = 0.16). In the obese cohort, men received a significantly lower weight-based phenytoin dose compared with women (15 mg/kg [IQR = 14.0-19.2], vs 19.9 mg/kg [IQR = 15.0-20.0], respectively; P = 0.008). Postload free phenytoin concentrations were similar between the 2 groups (male: 1.6 µg/mL [IQR = 1.2-2.1]; female: 1.7 µg/mL [IQR = 1.4-2.0]; P = 0.24). Conclusion and Relevance: Phenytoin and fosphenytoin LDs of at least 15 mg/kg of actual body weight are more likely to lead to desired free phenytoin concentrations. Obese female patients need a larger weight-based dose than male patients to achieve similar postload phenytoin concentrations.

Pharmacology of new and developing intravenous therapies for the management of seizures and epilepsy

INTRODUCTION

Antiepileptic drugs (AEDs) are administered orally for chronic use. Parenteral formulations might be necessary when the oral route is not feasible (e.g. an impairment of consciousness, trauma, dysphagia, gastrointestinal illness) or for treatment of seizure emergencies. At present, few intravenous (IV) formulations are available on the market.

AREAS COVERED

The purpose of this review is to summarize the pharmacological characteristics and clinical applications of IV medications that have been recently introduced to the armamentarium of epilepsy therapy or are currently being developed. Apart from AEDs, other compounds belonging to different pharmacological classes (e.g. diuretics, anesthetics), which have shown potential effectiveness in seizure control, are taken into consideration, and the pathophysiological premises supporting their use for epilepsy treatment are illustrated. The authors give particular focus to immunomodulatory and immunosuppressive agents, which have become the therapeutic cornerstones for immune-mediated epilepsies, despite regulatory obstacles.

EXPERT OPINION

In several circumstances, especially in the case of seizure-related emergencies, clinical practice seems not match literature-based evidence, and several IV AEDs are still used off-label. Strong evidence derived from randomized clinical trials (RCTs) is needed to support the effectiveness and tolerability of any therapeutic approach, however common and "accepted' it may be, in order to guarantee patient safety and well-being.

Levetiracetam circulating concentrations and response in status epilepticus

INTRODUCTION

Intravenous levetiracetam (LEV) is broadly used in the treatment of status epilepticus (SE). A loading dose is usually infused, aiming to reach quickly the range of plasma concentrations considered as therapeutic (12-46 mg/l). The aim of the study was to evaluate the response to LEV in SE, correlated exposure assessed by plasma concentration monitoring, as well as calculated exposure parameters.

MATERIALS & METHODS

We retrospectively analyzed a SE registry, including patients since 2015 with at least one available LEV plasma level measured less than 36 h after loading. A Bayesian maximum likelihood approach based on a population pharmacokinetic model was used to estimate LEV exposure parameters. We compared plasma levels and pharmacokinetics parameter estimates between responders and nonresponders. Therapeutic response was defined as SE cessation within 24 h following LEV introduction without a need for additional antiepileptic drug (AED).

RESULTS

We included 29 patients (45 plasma levels). Variability was salient in LEV loading doses (ranging between 17 and 38 mg/kg) and monitoring practice. There was no difference in median plasma concentrations (19.5 versus 21.5 mg/l; p = 0.71), median estimated LEV exposure (25.8 versus 37.0 mg/l; p = 0.61), peak (30.4 versus 41.5 mg/l; p = 0.36), or residual levels after loading dose (14.4 versus 20.5 mg/l; p = 0.07) between responders and nonresponders.

CONCLUSIONS

Levetiracetam exposure does not seem to differ significantly between responders and nonresponders; greater exposure was not associated with better outcome. Loading doses of 30 mg/kg seem, however, appropriate to quickly reach the target exposure level. The short LEV half-life makes standardized sampling measurement necessary to obtain directly interpretable LEV levels.

New Developments in Refractory Status Epilepticus

Status epilepticus (SE) is a medical emergency and presents with either a continuous prolonged seizure or multiple seizures without full recovery of consciousness in between them. The goals of treatment are prompt recognition, early seizure termination, and simultaneous evaluation for any potentially treatable cause. Improved understanding of the pathophysiology has led to a more practical definition. New data have emerged regarding the safety and efficacy of alternative agents, which are increasingly used in the management of these patients. Continuous electroencephalogram monitoring is more widely used and has revealed a higher incidence of subclinical seizures than was previously thought.

Updates in Refractory Status Epilepticus

Refractory status epilepticus is defined as persistent seizures despite appropriate use of two intravenous medications, one of which is a benzodiazepine. It can be seen in up to 40% of cases of status epilepticus with an acute symptomatic etiology as the most likely cause. New-onset refractory status epilepticus (NORSE) is a recently coined term for refractory status epilepticus where no apparent cause is found after initial testing. A large proportion of NORSE cases are eventually found to have an autoimmune etiology needing immunomodulatory treatment. Management of refractory status epilepticus involves treatment of an underlying etiology in addition to intravenous anesthetics and antiepileptic drugs. Alternative treatment options including diet therapies, electroconvulsive therapy, and surgical resection in case of a focal lesion should be considered. Short-term and long-term outcomes tend to be poor with significant morbidity and mortality with only one-third of patients reaching baseline neurological status.

Design, synthesis, biological evaluation, homology modeling and docking studies of (E)-3-(benzo[d][1,3]dioxol-5-ylmethylene) pyrrolidin-2-one derivatives as potent anticonvulsant agents

A series of (E)-3-(benzo[d][1,3]dioxol-5-ylmethylene)pyrrolidin-2-one derivatives were designed, synthesized, and evaluated for their anticonvulsant activities. In the preliminary screening, compounds 5, 6a-6f and 6h-6i showed promising anticonvulsant activities in MES model, while 6f and 6g represented protection against seizures at doses of 100 mg/kg and 0.5 h in scPTZ model. The most active compound 6d had a high-degree protection against the MES-induced seizures with ED₅₀ value of 4.3 mg/kg and TD₅₀ value of 160.9 mg/kg after intraperitoneal (i.p.) injection in mice, which provided 6d in a high protective index (TD₅₀/ED₅₀) of 37.4 comparable to the reference drugs. Beyond that, 6d has been selected and evaluated in vitro experiment to estimate the activation impact. Apparently, 6d clearly inhibits the Na_v1.1 channel. Our preliminary results provide new insights for the development of small-molecule activators targeting specifically Na_v1.1 channels to design potential drugs for treating epilepsy. The computational parameters, such as homology modeling, docking study, and ADME prediction, were made to exploit the results.

Newer Antiepileptic Drugs for Status Epilepticus in Adults: What's the Evidence?

Status epilepticus (SE) is one of the most frequent neurological emergencies. Despite this, understanding of its pathophysiology and evidence regarding its management is limited. Rapid, effective, and well-tolerated treatment to achieve seizure cessation is advocated to prevent brain damage or potentially lethal outcomes. The last two decades have witnessed an exponential increase in the number of available antiepileptic drugs (AEDs). These compounds, especially lacosamide and levetiracetam, in view of their intravenous formulation, have been increasingly prescribed in SE. These and other newer AEDs present a promising profile in terms of tolerability, with few centrally depressive effects, favorable pharmacokinetic properties, and fewer drug interactions than classical AEDs; conversely, they are more expensive. There is still no clear evidence to suggest a specific beneficial impact of newer AEDs on SE outcome, preventing any strong recommendation regarding their prescription in SE. Further comparative studies are urgently required to clarify their place and optimal use in the armamentarium of SE treatment.

Risk factors of early adverse drug reactions with phenytoin: A prospective inpatient cohort

INTRODUCTION

Phenytoin (PHT) is an effective and inexpensive antiepileptic drug (AED). However, its use has been limited for fear of adverse drug reactions (ADRs) and is being replaced by newer AED, increasing the costs and causing major budget problems, particularly for developing countries.

OBJECTIVE

The objective of this study was to determine ADR frequency, explore, and establish related risk factors.

METHODS

Prospective data were collected from a cohort of inpatients using PHT for the first time. Pharmacovigilance was performed during hospitalization and after one month from the discharge. Clinical variables, plasma levels, and concomitant medications were collected and their association with the occurrence of different ADRs was explored.

RESULTS

One hundred patients were included: 59 were women, and mean age was 59±21years. Thirty-three patients presented ADR, all moderate and idiosyncratic. The most frequent were rash (17%), fever (10%), and elevated transaminases (10%). Female gender (85% vs 52%, p=0.029), younger age (mean age: 49 vs 62years, p=0.032), and higher PHT plasmatic levels after IV-PO load (mean plasmatic levels: 18.6 vs 13.9μg/mL, p=0.040) were found to be associated with rash. A higher number of concomitant medications were also found to be associated with the risk for developing any ADR. The multivariate analysis revealed an association between rash and younger age (cut-off: 35years old; relative risk (RR)=11.7; p=0.026), and higher PHT plasmatic levels (cut-off: 16μg/mL; RR=12.5; p=0.021); and increased risk of elevated transaminases with use of PHT inductors (RR=18; p=0.006). A longer hospital stay was found in patients who developed fever (mean: 43days, p<0.0001) and elevated transaminases (mean: 26days, p=0.041) compared with patients without ADR (mean: 17days).

CONCLUSIONS

Phenytoin is a widely used AED associated with easily detectable ADR through structured pharmacovigilance. The development of ADR is associated with longer hospital stays. Recognition of local risk factors may lead to ADR prevention in a near future. Larger studies are needed to better define PHT-related ADR risk profile and to individualize treatment regimens.

New Developments in Refractory Status Epilepticus

Status epilepticus (SE) is a medical emergency and presents with either a continuous prolonged seizure or multiple seizures without full recovery of consciousness in between them. The goals of treatment are prompt recognition, early seizure termination, and simultaneous evaluation for any potentially treatable cause. Improved understanding of the pathophysiology has led to a more practical definition. New data have emerged regarding the safety and efficacy of alternative agents, which are increasingly used in the management of these patients. Continuous electroencephalogram monitoring is more widely used and has revealed a higher incidence of subclinical seizures than was previously thought.

Newer Antiepileptic Drugs in Status Epilepticus: Prescription Trends and Outcomes in Comparison with Traditional Agents

INTRODUCTION

Newer antiepileptic drugs (AEDs) are increasingly prescribed; however, relatively limited data are available regarding their use in status epilepticus (SE) and the impact on outcome.

OBJECTIVES

The aim of this study was to explore the evolution in prescription patterns of newer and traditional AEDs in this clinical setting, and their association with prognosis.

METHODS

We analyzed our prospective adult SE registry over a 10-year period (2007-2016) and assessed the yearly use of newer and traditional AEDs and their association with mortality, return to baseline conditions at discharge, and SE refractoriness, defined as treatment resistance to two AEDs, including benzodiazepines.

RESULTS

In 884 SE episodes, corresponding to 719 patients, the prescription of at least one newer AED increased from 0.38 per SE episode in 2007 to 1.24 per SE episode in 2016 (mostly due to the introduction of levetiracetam and lacosamide). Traditional AEDs (excluding benzodiazepines) decreased over time from 0.74 in 2007 to 0.41 in 2016, correlating with the decreasing use of phenytoin. The prescription of newer AEDs was independently associated with a lower chance of return to baseline conditions at discharge (odds ratio [OR] 0.58, 95% confidence interval [CI] 0.40-0.84) and a higher rate of SE refractoriness (OR 19.84, 95% CI 12.76-30.84), but not with changes in mortality (OR 1.08, 95% CI 0.58-2.00).

CONCLUSION

We observed a growing trend in the prescription of newer AEDs in SE over the last decade; however, our findings might suggest an associated increased risk of SE refractoriness and new disability at hospital discharge. Pending prospective, comparative studies, this may justify some caution in the routine use of newer AEDs in SE.

Valproate Protein Binding Is Highly Variable in ICU Patients and Not Predicted by Total Serum Concentrations: A Case Series and Literature Review

STUDY OBJECTIVE

The free fraction of valproate (the pharmacologically active moiety, normally 5-10%) may vary significantly in critically ill patients, but this topic is understudied, with only four prior intensive care unit (ICU) case reports. The objective of this study was to evaluate the range of valproate plasma protein binding in ICU patients.

DESIGN

Observational study of consecutive ICU patients.

SETTING

Neurocritical and medical critical care services in a nonuniversity academic medical center.

PATIENTS

Consecutive ICU patients treated with valproate with serum albumin less than 4 g/dl.

MEASUREMENTS AND MAIN RESULTS

Simultaneous total and free trough serum valproate concentrations were measured as were serum creatinine, blood urea nitrogen, albumin, platelets, and transaminase values. The reference concentration range was 50-125 mg/L (total) and 5-17 mg/L (free). Valproate concentrations were categorized as within reference range, low, or high, and as concordant if both concentrations were in the same category. Data are reported as median (interquartile range). Fifteen patients (nine men) were evaluated. The median age was 63 (34-70) years. The valproate dose was 3 g/day (35 mg/kg/day). No patient had a valproate free fraction of 5-10%; the median was 48%, and the range was 15-89%. Total and free concentrations showed poor correlation (0.43) and were concordant in only two patients (both in the reference range). Free valproate concentration was poorly predicted by an equation correcting for albumin (r = 0.45). Suspected adverse drug events occurred in 10 patients: hyperammonemia in 7 of 12 tested (58%), elevated transaminases in 2 of 15 (13%), and thrombocytopenia in 5 of 15 (33%).

CONCLUSIONS

Protein binding of valproate was highly inconsistent in this cohort of ICU patients, and total valproate concentrations did not predict free concentrations, even when correcting for albumin. Additional research to define best practice for dosing and monitoring valproate and the relationship between free valproate concentrations and clinical or adverse effects in ICU patients is needed.

[Not Available]

Zusammenfassung. Der Status epilepticus, vor allem der konvulsive tonisch-klonische (Grand mal) Status epilepticus, ist ein Notfall, der zu einer sofortigen Behandlung führen muss. Die frühe Behandlung ist effektiver als der spätere Beginn, ebenso wie der Einsatz standardisierter Therapieprotokolle. Nach der Gabe von Benzodiazepinen muss die Aufdosierung eines Antikonvulsivums (Levetiracetam, Valproat oder Phenytoin) erfolgen, um das Wiederauftreten von Anfällen zu verhindern. Beim refraktären Status epilepticus werden die Anästhetika Propofol oder Midazolam (oder Thiopental) vorzugsweise unter EEG-Ableitung mit einem Burst-Suppressions-Muster eingesetzt. Neben der raschen Therapie sollte die Diagnostik nach der Ursache des Status epilepticus nicht vergessen werden. Insbesondere bei Persistenz sollte immer auch die Überprüfung der Diagnose erfolgen, um das Vorliegen eines Pseudostatus nicht-epileptischer Anfälle nicht zu übersehen.

The use and yield of continuous EEG in critically ill patients: A comparative study of three centers

OBJECTIVE

Continuous EEG (cEEG) monitoring of critically ill patients has gained widespread use, but there is substantial reported variability in its use. We analyzed cEEG and antiseizure drug (ASD) usage at three high volume centers.

METHODS

We utilized a multicenter cEEG database used daily as a clinical reporting tool in three tertiary care sites (Emory Hospital, Brigham and Women's Hospital and Yale - New Haven Hospital). We compared the cEEG usage patterns, seizure frequency, detection of rhythmic/periodic patterns (RPP), and ASD use between the sites.

RESULTS

5792 cEEG sessions were analyzed. Indication for cEEG monitoring and recording duration were similar between the sites. Seizures detection rate was nearly identical between the three sites, ranging between 12.3% and 13.6%. Median time to first seizure and detection rate of RPPs were similar. There were significant differences in doses of levetiracetam, valproic acid, and lacosamide used between the three sites.

CONCLUSIONS

There was remarkable uniformity in seizure detection rates within three high volume centers. In contrast, dose of ASD used frequently differed between the three sites.

SIGNIFICANCE

These large volume data are in line with recent guidelines regarding cEEG use. Difference in ASD use suggests discrepancies in how cEEG results influence patient management.

The SAMUKeppra study in prehospital status epilepticus: lessons for future study

In the Lancet Neurology article "Prehospital treatment with levetiracetam plus clonazepam or placebo plus clonazepam in status epilepticus (SAMUKeppra): a randomised, double-blind, phase 3 trial" the authors conducted a prehospital, randomized controlled study to determine which treatment is more effective for status epilepticus (SE): benzodiazepine alone, or in combination with levetiracetam (LEV). Although the study had negative results, several aspects of the trial design likely masked any added effect that LEV may have had in controlling SE, including: higher doses of benzodiazepines, lower thresholds for determining cessation of SE, and a smaller sample size. Regardless, the study reaffirms the effectiveness and importance of early and adequate benzodiazepine dosing and helps guide us in designing future studies for treatment of SE.