Levetiracetam versus phenytoin for second-line treatment of convulsive status epilepticus in children (ConSEPT): an open-label, multicentre, randomised controlled trial

Continuous EEG use and status epilepticus treatment in Australasia: a practice survey of Australian and New Zealand epileptologists

Objective

Continuous electroencephalography (cEEG) is increasingly used to detect non-convulsive seizures in critically ill patients but is not widely practised in Australasia. Use of cEEG is also influencing the management of status epilepticus (SE), which is rapidly evolving. We aimed to survey Australian and New Zealand cEEG use and current treatment of SE

Methods

A web-based survey was distributed to Epilepsy Society of Australia (ESA) members, between October and November 2019. Adult and paediatric neurologists/epileptologists with ESA membership involved in clinical epilepsy care and cEEG interpretation were invited to participate.

Results

Thirty-five paediatric/adult epileptologists completed the survey, 51% with over 10 years of consultant experience. cEEG was always available for only 31% of respondents, with the majority having no or only ad hoc access to cEEG. Lack of funding (74%) and personnel (71%) were the most common barriers to performing cEEG. Although experience with SE was common, responses varied regarding treatment approaches for both convulsive and non-convulsive SE. Escalation to anaesthetic treatment of convulsive SE tended to occur later than international guideline recommendations. There was general agreement that formal training in cEEG and national guidelines for SE/cEEG were needed.

Conclusions

cEEG availability remains limited in Australia, with lack of funding and resourcing being key commonly identified barriers. Current opinions on the use of cEEG and treatment of SE vary reflecting the complexity of management and a rapidly evolving field. An Australian-based guideline for the management of SE, including the role of cEEG is recommended.

Emergency management of the paediatric patient with convulsive status epilepticus

This guideline addresses the emergency management of convulsive status epilepticus (CSE) in children and infants older than 1 month of age. It replaces a previous position statement from 2011, and includes a new treatment algorithm and table of recommended medications based on new evidence and reflecting the evolution of clinical practice over the past several years. This statement emphasizes the importance of timely pharmacological management of CSE, and includes some guidance for diagnostic approach and supportive care.

La prise en charge d’urgence du patient pédiatrique en état de mal épileptique convulsif

Les présentes lignes directrices portent sur la prise en charge d’urgence de l’état de mal épileptique convulsif chez les nourrissons âgés de plus d’un mois et les enfants. Elles remplacent un document de principes publié en 2011 et comprennent un nouvel algorithme thérapeutique, de même qu’un tableau des médicaments recommandés en fonction de nouvelles données probantes qui reflètent l’évolution de la pratique clinique des quelques dernières années. Le présent document de principes souligne l’importance d’un traitement pharmacologique rapide de l’état de mal épileptique convulsif et contient des conseils relativement à la démarche diagnostique et aux soins de soutien.

Update on the management of status epilepticus

PURPOSE OF REVIEW

Randomized controlled trials investigating the initial pharmacological treatment of status epilepticus have been recently published. Furthermore, status epilepticus arising in comatose survivors after cardiac arrest has received increasing attention in the last years. This review offers an updated assessment of status epilepticus treatment in these different scenarios.

RECENT FINDINGS

Initial benzodiazepines underdosing is common and correlates with development of status epilepticus refractoriness. The recently published ESETT trial provides high-level evidence regarding the equivalence of fosphenytoin, valproate, and levetiracetam as a second-line option. Myoclonus or epileptiform transients on electroencephalography occur in up to 1/3 of patients surviving a cardiac arrest. Contrary to previous assumptions regarding an almost invariable association with death, at least 1/10 of them may awaken with reasonably good prognosis, if treated. Multimodal prognostication including clinical examination, EEG, somatosensory evoked potentials, biochemical markers, and neuroimaging help identifying patients with a chance to recover consciousness, in whom a trial with antimyoclonic compounds and at times general anesthetics is indicated.

SUMMARY

There is a continuous, albeit relatively slow progress in knowledge regarding different aspect of status epilepticus; recent findings refine some treatment strategies and help improving patients' outcomes. Further high-quality studies are clearly needed to further improve the management of these patients, especially those with severe, refractory status epilepticus forms.

A retrospective cohort study of super-refractory status epilepticus in a tertiary neuro-ICU setting

PURPOSE

Over the last decade, the range of treatments available for the management of super-refractory status epilepticus (SRSE) has expanded. However, it is unclear whether this has had an impact on its high mortality and morbidity. The aim of this study was to investigate whether there has been a change in the outcome of SRSE over time in a neurological intensive care unit (ICU) within a tertiary centre.

METHODS

Analysis of a retrospective cohort of 53 admissions from 45 patients to the neurological ICU at the National Hospital for Neurology and Neurosurgery, Queen Square, London, between January 2004 and September 2018.

RESULTS

Significant reductions were observed in both duration of SRSE over time and in the time spent in ICU, suggesting that treatment quality has improved over time. A median of four antiseizure drugs (ASDs) were given prior to seizure resolution. In 23 % resolution of SRSE occurred following optimisation of current treatment rather than introduction of a new ASD. The mortality rate was very low at 11 % by 6 months; however, there was no indication of improvement in outcome as all surviving patients had a modified Rankin scale score of 3-5 upon discharge from ICU, classified as moderate-to-severe disability.

CONCLUSION

Neither the survival rate nor the outcome score changed significantly over time, suggesting that changes in the treatment of SRSE have had no impact on patient outcome.

Pediatric emergency medicine literature 2020

Most children are treated at general Emergency Departments (EDs) and not specialized pediatric EDs. Therefore, it is crucial for emergency medicine physicians to be aware of recent developments in pediatric emergency medicine. Often impactful articles on pediatric emergency medicine are not published in the journals regularly studied by general emergency medicine physicians. We selected ten studies that we found impactful, robust, and relevant for practicing general emergency physicians. This review includes studies of status epilepticus, cardiac arrest, asthma, infant fever, wound care, rapid sequence intubation, coronavirus, and trauma.

Intramuscular Midazolam for treatment of Status Epilepticus

INTRODUCTION

Status epilepticus (SE) is a common neurological and medical emergency. It has high mortality and morbidity rates, which typically correlate with seizure semiology and duration; therefore, prompt and proper pharmacological intervention is paramount. In a pre-hospital setting, establishing venous access can be difficult, so other routes of drug administration should be considered.

AREAS COVERED

The paper summarizes the data from the literature and provides an evaluation of the efficacy and safety of intramuscular midazolam (IM MDZ) as it pertains to the management of acute seizures and SE.

EXPERT OPINION

The cascade of events involved in the genesis and sustenance of seizures, if not promptly stopped, lead to the perpetuation of the condition and may contribute to the refractoriness of pharmacological treatment. Hence, non-venous routes for drug administration were developed to allow untrained personnel to rapidly stop seizures. Among benzodiazepines (BDZs), IM MDZ is at least as effective and safe as other intravenously administered BDZs. Moreover, thanks to IM MDZ's favorable pharmacodynamic and pharmacokinetic profile, it is a promising alternative to other non-venous drugs such as intranasal-MDZ, buccal-MDZ, and rectal-diazepam in the pre-hospital management of SE cases with motor features.

Safety, tolerability, and pharmacokinetics of weight-based IV loading dose of lacosamide in the ICU

Among the newer antiseizure medications, lacosamide (LCM) has been increasingly used for acute seizures and status epilepticus in intensive care unit (ICU). We reviewed retrospectively weight-based dosing of IV LCM in patients admitted to ICU with acute seizures and status epilepticus. We have analyzed 354/382 patient treated with IV LCM in ICU during the years 2013-2016. Data collected were age, total body weight, body mass index (BMI), loading dose, post-IV infusion LCM blood level, duration of infusion, blood pressure, heart rate, oxygen saturation, mean arterial pressures, and documented initiation of pressor agents during or within in 30 min of infusion. Larger doses >8 mg/kg of IV LCM that can be safely administered in ICU patients produce effective plasma levels of 15-20 μg/ml with relatively constant volume of distribution.

Early Use of Antiseizure Medication in Mechanically Ventilated Traumatic Brain Injury Cases: A Retrospective Pediatric Health Information System Database Study

OBJECTIVES

Traumatic brain injury is a leading cause of morbidity and mortality in children. Post-traumatic seizures occur in 25% of children with severe traumatic brain injury and may worsen outcomes. Our objective was to use a retrospective cohort study to examine the association between the early seizure occurrence and the choice of early antiseizure medication in children with traumatic brain injury.

DESIGN

Retrospective cohort study using the Pediatric Health Information Systems database, 2010-2017.

SETTING

Fifty-one U.S. children's hospitals.

PATIENTS

Children (< 18 yr old at admission) with diagnostic codes for traumatic brain injury who were mechanically ventilated at the time of admission and with hospital length of stay greater than 24 hours.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 3,479 children were identified via coding and including in the analysis. Patients receiving antiseizure medication starting day 0 with levetiracetam were compared with those receiving phenytoin. The outcome was seizure occurrence, identified using validated International Classification of Diseases, 9th Revision, Clinical Modification and International Classification of Diseases, 10th Revision, Clinical Modification diagnosis codes. The median (interquartile range) age of patients was 4 (1-11) years, and the most common mechanism of injury was motor vehicle accident, occurring in 960 of patients (27%). A total of 2,342 patients (67%) received levetiracetam on day 0 and 1,137 patients (33%) received phenytoin on day 0. Totally 875 patients (37%) receiving levetiracetam on day 0 developed seizures, compared with 471 patients (41%) receiving phenytoin on day 0 (p = 0.02). Upon multivariable analysis adjusting for age, injury by child abuse, subdural hemorrhage, ethnicity, and admission year, children receiving phenytoin on day 0 were 1.26 (95% CI, 1.07-1.48) times more likely to be associated with post-traumatic seizure occurrence, compared with children receiving levetiracetam on day 0 (p = 0.01).

CONCLUSIONS

Early administration of levetiracetam was associated with less-frequent seizure occurrence than early administration of phenytoin in mechanically ventilated children with traumatic brain injury. Additional studies are necessary to determine if the association is causal or due to unmeasured confounders and/or selection bias.

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.

Emergency Neuropharmacology

Management of acute neurologic disorders in the emergency department is multimodal and may require the use of medications to decrease morbidity and mortality secondary to neurologic injury. Clinicians should form an individualized treatment approach with regard to various patient specific factors. This review article focuses on the pharmacotherapy for common neurologic emergencies that present to the emergency department, including traumatic brain injury, central nervous system infections, status epilepticus, hypertensive emergencies, spinal cord injury, and neurogenic shock.

Preferential Antiseizure Medications in Pediatric Patients with Convulsive Status Epilepticus: A Systematic Review and Network Meta-Analysis

BACKGROUND AND OBJECTIVE

The optimal choice for first- and second-line antiseizure medications for pediatric patients with convulsive status epilepticus remains ambiguous. The present study aimed to estimate the comparative effect on the efficacy and safety of different antiseizure medications in pediatric patients with status epilepticus and provide evidence for clinical practice.

METHODS

We searched PubMed, EMBASE, and the Cochrane Library for eligible randomized controlled trials. Inclusion criteria included: (1) pediatric patients; (2) diagnosis of status epilepticus; and (3) randomized controlled trials. Exclusion criteria were: (1) mixed population without a pediatric subgroup analysis; (2) not status epilepticus; (3) received the study drug prior to admission; (4) sample size fewer than 30; and (5) not randomized controlled trials. Primary outcome was seizure cessation. Secondary outcomes were seizure recurrence within 24 h, respiratory depression, and admission to an intensive care unit. The hierarchy of competing antiseizure medications was presented using the surface under the cumulative ranking curve.

RESULTS

Eight first-line antiseizure medication studies involving 1686 participants and eight second-line antiseizure medication studies involving 1711 participants were eligible for analysis. Midazolam, diazepam, lorazepam, and paraldehyde were administered as first-line antiseizure medications. Valproate, phenobarbital, phenytoin, fosphenytoin, and levetiracetam were investigated as second-line antiseizure medications. No significant differences were observed across first- and second-line antiseizure medications. Midazolam ranked the best for primary and secondary outcomes among the first-line antiseizure medications. Phenobarbital ranked the best for seizure cessation and a lower risk of admission to the intensive care unit. Valproate had superiority in preventing recurrence within 24 h. Levetiracetam had the lowest probability of developing respiratory depression.

CONCLUSIONS

This study demonstrated the hierarchy of competing interventions. Midazolam could be a better option for first-line treatment. Phenobarbital, levetiracetam, and valproate had their respective superiority in the second-line intervention. This study may provide useful information for clinical decision making under different circumstances.

Levetiracetam as an alternative to phenytoin for second-line emergency treatment of children with convulsive status epilepticus: the EcLiPSE RCT

BACKGROUND

Convulsive status epilepticus is the most common neurological emergency in children. Its management is important to avoid or minimise neurological morbidity and death. The current first-choice second-line drug is phenytoin (Epanutin, Pfizer Inc., New York, NY, USA), for which there is no robust scientific evidence.

OBJECTIVE

To determine whether phenytoin or levetiracetam (Keppra, UCB Pharma, Brussels, Belgium) is the more clinically effective intravenous second-line treatment of paediatric convulsive status epilepticus and to help better inform its management.

DESIGN

A multicentre parallel-group randomised open-label superiority trial with a nested mixed-method study to assess recruitment and research without prior consent.

SETTING

Participants were recruited from 30 paediatric emergency departments in the UK.

PARTICIPANTS

Participants aged 6 months to 17 years 11 months, who were presenting with convulsive status epilepticus and were failing to respond to first-line treatment.

INTERVENTIONS

Intravenous levetiracetam (40 mg/kg) or intravenous phenytoin (20 mg/kg).

MAIN OUTCOME MEASURES

Primary outcome - time from randomisation to cessation of all visible signs of convulsive status epilepticus. Secondary outcomes - further anticonvulsants to manage the convulsive status epilepticus after the initial agent, the need for rapid sequence induction owing to ongoing convulsive status epilepticus, admission to critical care and serious adverse reactions.

RESULTS

Between 17 July 2015 and 7 April 2018, 286 participants were randomised, treated and consented. A total of 152 participants were allocated to receive levetiracetam and 134 participants to receive phenytoin. Convulsive status epilepticus was terminated in 106 (70%) participants who were allocated to levetiracetam and 86 (64%) participants who were allocated to phenytoin. Median time from randomisation to convulsive status epilepticus cessation was 35 (interquartile range 20-not assessable) minutes in the levetiracetam group and 45 (interquartile range 24-not assessable) minutes in the phenytoin group (hazard ratio 1.20, 95% confidence interval 0.91 to 1.60; p = 0.2). Results were robust to prespecified sensitivity analyses, including time from treatment commencement to convulsive status epilepticus termination and competing risks. One phenytoin-treated participant experienced serious adverse reactions.

LIMITATIONS

First, this was an open-label trial. A blinded design was considered too complex, in part because of the markedly different infusion rates of the two drugs. Second, there was subjectivity in the assessment of 'cessation of all signs of continuous, rhythmic clonic activity' as the primary outcome, rather than fixed time points to assess convulsive status epilepticus termination. However, site training included simulated demonstration of seizure cessation. Third, the time point of randomisation resulted in convulsive status epilepticus termination prior to administration of trial treatment in some cases. This affected both treatment arms equally and had been prespecified at the design stage. Last, safety measures were a secondary outcome, but the trial was not powered to demonstrate difference in serious adverse reactions between treatment groups.

CONCLUSIONS

Levetiracetam was not statistically superior to phenytoin in convulsive status epilepticus termination rate, time taken to terminate convulsive status epilepticus or frequency of serious adverse reactions. The results suggest that it may be an alternative to phenytoin in the second-line management of paediatric convulsive status epilepticus. Simple trial design, bespoke site training and effective leadership were found to facilitate practitioner commitment to the trial and its success. We provide a framework to optimise recruitment discussions in paediatric emergency medicine trials.

FUTURE WORK

Future work should include a meta-analysis of published studies and the possible sequential use of levetiracetam and phenytoin or sodium valproate in the second-line treatment of paediatric convulsive status epilepticus.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN22567894 and European Clinical Trials Database EudraCT number 2014-002188-13.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 58. See the NIHR Journals Library website for further project information.

Levetiracetam vs. phenytoin as 2nd-line treatment for status epilepticus: A systematic review and meta-analysis

OBJECTIVE

The objective of the study was to perform a systematic review and meta-analysis to evaluate the efficacy and safety of levetiracetam (LEV) or phenytoin (PHT) as second-line treatment for status epilepticus (SE).

METHODS

PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Latin American and Caribbean Health Sciences Literature (LILACS), Scopus, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and Google Scholar were assessed for prospective randomized trials comparing LEV with PHT as second-line treatment of SE published from inception until December 18th, 2019. The primary outcome was seizure cessation. Data were analyzed using a random-effects model. Quality analysis was performed using version 2 of the Cochrane risk-of-bias tool (RoB 2). The study protocol was registered on PROSPERO (CRD42020136417).

RESULTS

Nine studies with a total of 1732 patients were included. Overall, seizure cessation occurred in 657 of 887 (74%) of patients in the LEV group and 600 of 845 (71%) in the PHT group. Treatment success did not differ significantly between groups, and the relative risk (RR) was 1.05 (95% confidence interval (CI): 0.98-1.12; I² = 53%). Six of the studies were at low risk of bias, one study had some risk, and two studies had high risk.

CONCLUSIONS

The use of LEV or PHT as second-line agents after benzodiazepine (BZD) for the treatment of SE was not associated with a difference in seizure cessation. Because there are minimal differences in efficacy at this time, clinicians should consider alternative factors when deciding on an antiepileptic drug (AED).

Efficacy and safety profile of intravenous levetiracetam versus phenytoin in convulsive status epilepticus and acute repetitive seizures in children

PURPOSE

Although phenytoin is one of the most commonly used antiepileptic drugs (AEDs), it has potential serious side effects and drug interactions. Levetiracetam is a relatively newer AED with favorable pharmacokinetics and could be an effective and safer option for the treatment of convulsive status epilepticus (CSE). We aimed to compare the efficacy and safety profile of intravenous levetiracetam and phenytoin as second-line treatment agents in children with CSE and acute repetitive seizures (ARS).

METHOD

Two hundred seventy-seven patients aged between 1 month and 18 years who received intravenous levetiracetam or phenytoin as a second-line AED with the diagnosis of CSE or ARS were retrospectively evaluated. Drug efficacy was defined as control of seizures without the need for any additional medication after completion of the infusion and no recurrence in the following 12 h. The primary outcome was drug efficacy. The secondary outcomes included application of an additional second-line AED, induction of anesthesia, and admission to the intensive care unit (ICU), and drug-related adverse reactions.

RESULTS

No differences were found between the two treatment groups with regard to patient characteristics and seizure type. The efficacy of levetiracetam was higher than that of phenytoin (77.6% vs 57.7%, P = 0.011) in children with CSE. There was no significant difference between the efficacy rates of levetiracetam and phenytoin for ARS (55.8% vs 58.8%, P = 0.791). Overall, drug efficacy was 70.9% for levetiracetam and 58.1% for phenytoin (P = 0.048). For CSE, the need for additional second-line treatment, anesthesia induction, and ICU admission was higher in the phenytoin group (P = 0.001, P = 0.038, P = 0.02, respectively). Drug-related adverse reactions were more frequent in the phenytoin group than the levetiracetam group (23.3% vs 1.4%; P < 0.001). The most common adverse reaction in the phenytoin group was hypotension. Phenytoin-related anaphylaxis was detected in one patient. No serious adverse effects related to levetiracetam were observed.

CONCLUSIONS

Intravenous levetiracetam seems as effective as intravenous phenytoin in emergency treatment of children with ARS and more effective for CSE in stopping the seizure with less risk of recurrence. Levetiracetam has fewer cardiovascular side effects and has a safer profile than phenytoin. Intravenous levetiracetam is a favorable option as a first second-line AED for pediatric seizures.

Pharmacokinetic Monitoring of Levetiracetam in Portuguese Refractory Epileptic Patients: Effect of Gender, Weight and Concomitant Therapy

Levetiracetam is a second-generation antiepileptic drug, widely used in the treatment of focal and generalized epilepsy due to its pharmacokinetic and safety profiles. Its pharmacokinetic monitoring is ascribed as useful to personalize its dosing regimen. The aim of the present study was to describe, for the first time, the pharmacokinetics of levetiracetam in Portuguese refractory epileptic patients. Therefore, a retrospective study was carried out on 65 Portuguese refractory epileptic patients (pharmacokinetic study: 48; validation study: 17) admitted to the Refractory Epilepsy Centre of the Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal. The pharmacokinetic parameters of levetiracetam were estimated by applying a one-compartment model with first-order absorption and elimination analysis. Male patients showed higher distribution volume (Vd/F) and oral clearance (CL/F) than female patients (median Vd/F: 52.40 L in males and 38.60 L in females, p = 0.011; median CL/F: 4.71 L/h in males and 3.91 L/h in females, p = 0.028). Higher values of Vd/F (p = 0.026) and CL/F (p = 0.003) were also found in overweight patients relative to normal weight and obese patients. Carbamazepine was the co-administered antiepileptic drug that mostly affected the pharmacokinetics of levetiracetam, increasing both Vd/F (61.30 L with carbamazepine and 39.10 L without carbamazepine, p = 0.007) and CL/F (6.71 L/h with carbamazepine and 3.91 L/h without carbamazepine, p < 0.001). The pharmacokinetics of levetiracetam was affected by gender, body mass index, and co-administration of carbamazepine. This study highlights the impact of several factors on the CL/ and Vd/F of levetiracetam when administered to refractory epileptic patients. The importance of its pharmacokinetic monitoring in clinical pharmacy stands out, thereby enabling the optimization of antiepileptic drug therapy.

The burden of decisional uncertainty in the treatment of status epilepticus

OBJECTIVE

Treatments for convulsive status epilepticus (SE) have a wide range of effectiveness. The estimated effectiveness of non-intravenous benzodiazepines (non-IV BZDs) ranges from approximately 70% to 90% and the estimated effectiveness of non-benzodiazepine antiseizure medications (non-BZD ASMs) ranges from approximately 50% to 80%. This study aimed to quantify the clinical and economic burden of decisional uncertainty in the treatment of SE.

METHODS

We performed a decision analysis that evaluates how decisional uncertainty on treatment choices for SE impacts hospital admissions, intensive care unit (ICU) admissions, and costs in the United States. We evaluated treatment effectiveness based on the available literature.

RESULTS

Use of a non-IV BZD with high estimated effectiveness, like intranasal midazolam, rather than one with low estimated effectiveness, like rectal diazepam, would result in a median (p₂₅ -p₇₅ ) reduction in hospital admissions from 6 (3.9-8.8) to 1.1 (0.7-1.8) per 100 cases and associated cost reductions of $638 ($289-$1064) per pediatric patient and $1107 ($972-$1281) per adult patient. For BZD-resistant SE, use of a non-BZD ASM with high estimated effectiveness, like phenobarbital, rather than one with low estimated effectiveness, like phenytoin/fosphenytoin, would result in a reduction in ICU admissions from 9.1 (7.3-11.2) to 3.9 (2.6-5.5) per 100 cases and associated cost reduction of $1261 ($445-$2223) per pediatric patient and $319 ($-93-$806) per adult patient. Sensitivity analyses showed that relatively minor improvements in effectiveness may lead to substantial reductions in downstream hospital admissions, ICU admissions, and costs.

SIGNIFICANCE

Decreasing decisional uncertainty and using the most effective treatments for SE may substantially decrease hospital admissions, ICU admissions, and costs.

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.

Status Epilepticus in Children

For various reasons, status epilepticus in children is different than in adults. Pediatric specificities include status epilepticus epidemiology, underlying etiologies, pathophysiological mechanisms, and treatment options. Relevant data from the literature are presented for each of them, and questions remaining open for future studies on status epilepticus in childhood are listed.

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.

Intramuscular Versus Buccal Midazolam for Pediatric Seizures: A Randomized Double-Blinded Trial

BACKGROUND

We compared the efficacy and safety of intramuscular with buccal midazolam as first-line treatment for active seizures in children brought to the emergency department.

METHODS

In a double-blind, double-dummy randomized trial, patients with an active seizure lasting more than five minutes received blinded treatments on arrival. We employed deferred consent. The proportion of patients with cessation of seizure within five minutes of drug administration was the primary efficacy outcome; proportions needing additional medication to control seizure, duration of seizure activity, and side effects were secondary outcomes.

RESULTS

We enrolled 150 children presenting with active seizure, age range 4.5 to 167.5 months. Cessation of seizure occurred in 61% of the intramuscular and 46% of the buccal treatment groups, (P = 0.07, difference 15.5%, 95% confidence interval for the difference -1.0 to 32.0%). Proportions requiring additional anti-seizure treatment were 39% in the intramuscular and 51% in the buccal groups. Mean duration of seizure activity after administration of study medication was 15.9 minutes (S.D. 28.7) in the intramuscular and 17.8 minutes (S.D. 27.5) in the buccal group. One patient in the intramuscular group developed respiratory depression and hypotension; there were no side effects attributed to investigational treatment in the buccal group.

CONCLUSIONS

Efficacy and safety of intramuscular midazolam as first-line treatment for pediatric seizures compare favorably to that of buccal midazolam.

Clinical Effectiveness of Levetiracetam Compared to Fosphenytoin in the Treatment of Benzodiazepine Refractory Convulsive Status Epilepticus

OBJECTIVES

To determine whether levetiracetam is an alternative to fosphenytoin to control Benzodiazepine Refractory Status Epilepticus (BRSE) in pediatric population and also to compare the acute drug related side-effects and ventilation requirement among the both arms of anti-epileptic drug therapy.

METHODS

All consecutive children admitted with BRSE were randomized to group A, who received fosphenytoin at 20 mg/kg phenytoin equivalents (PE) dose and group B who received levetiracetam at 40 mg/kg over 10 min. Time to terminate seizure (response latency) was measured. If seizure remained refractory after 20 min of test drug administration, appropriate drug escalation was made according to pediatrician's discretion. All primary and secondary outcome measures were compared between the two therapeutic groups.

RESULTS

Of 61 children enrolled over 18 mo period, 29 (47.5%) were randomized to group A and 32 (52.5%) were randomized to Group B. Baseline characteristics were comparable between the two groups. Among 61 children, 58(98%) required Pediatric Intensive Care Unit (PICU) admission and among those 5(8.2%) children required mechanical ventilation. Duration of PICU stay, hospital stay, the response latency and seizure recurrence were compared between both groups. Significant number of children received additional anti-epileptic drugs (AEDs) in fosphenytoin group [9/29(31%)] compared to levetiracetam group [2/32(7%)] to control seizure.

CONCLUSIONS

Levetiracetam may be an effective alternative to fosphenytoin in management of BRSE in children but multicentric trials with large sample size are needed to substantiate this observation.

Establishing a research network

Multicentre research provides advantages over single-centre research by maximising available patient numbers while pooling varied expertise and resources available across different participating investigators and sites. The increased complexity of multicentre regulatory approvals, communication and study management, can be mitigated by the formation of a research network where multicentre efforts move from ad hoc, single projects to formalised ongoing collaboration. Network research helps prioritise research efforts and importantly fosters the development of a collaborative track record in terms of research expertise, research capacity and grant success. It also has the potential to rapidly change patient care across many hospitals as research results will be more generalizable and definitive. This paper sets out the key elements of network research, its benefits and possible challenges drawing on the example of PREDICT (Paediatric Research in Emergency Departments International Collaborative) an established paediatric emergency research network in Australia and New Zealand.

Efficacy, Safety, and Economics of Intravenous Levetiracetam for Status Epilepticus: A Systematic Review and Meta-Analysis

Objective

To evaluate efficacy, safety, and economics profiles of intravenous levetiracetam (LEV) for status epilepticus (SE).

Methods

We searched PubMed, Embase, the Cochrane Library, Clinicaltrials.gov, and OpenGrey.eu for eligible studies published from inception to June 12^th 2019. Meta-analyses were conducted using random-effect model to calculate odds ratio (OR) of included randomized controlled trials (RCTs) with RevMan 5.3 software.

Results

A total of 478 studies were obtained. Five systematic reviews (SRs)/meta-analyses, 9 RCTs, 1 non-randomized trial, and 27 case series/reports and 1 economic study met the inclusion criteria. Five SRs indicated no statistically significant difference in rates of seizure cessation when LEV was compared with lorazepam (LOR), phenytoin (PHT), or valproate (VPA). Pooled results of included RCTs indicated no statistically significant difference in seizure cessation when LEV was compared with LOR [OR = 1.04, 95% confidence interval (CI) 0.37 to 2.92], PHT (OR = 0.90, 95% CI 0.64 to 1.27), and VPA (OR = 1.47, 95% CI 0.81 to 2.67); and no statistically significant difference in seizure freedom within 24 h compared with LOR [OR = 1.83, 95% CI 0.57 to 5.90] and PHT (OR = 1.08, 95% CI 0.63 to 1.87). Meanwhile, LEV did not increase the risk of mortality during hospitalization compared with LOR (OR = 1.03, 95% CI 0.31 to 3.39), PHT (OR = 0.89, 95% CI 0.37 to 2.10), VPA (OR = 1.28, 95% CI 0.32 to 5.07), and placebo (plus clonazepam, OR = 0.73, 95% CI 0.16 to 3.38). LEV had lower need for artificial ventilation (OR = 0.23, 95% CI 0.06 to 0.92) and a lower risk of hypotension (OR = 0.15, 95% CI 0.03 to 0.84) compared to LOR. A trend of lower risk of hypotension and higher risk of agitation was found when LEV was compared with PHT. Case series and case report studies indicated psychiatric and behavioral adverse events of LEV. Cost-effectiveness evaluations indicated LEV as the most cost-effective non-benzodiazepines anti-epileptic drug (AED).

Conclusions

LEV has a similar efficacy as LOR, PHT, and VPA for SE, but a lower need for ventilator assistance and risk of hypotension, thus can be used as a second-line treatment for SE. However, more well-conducted studies to confirm the role of intravenous LEV for SE are still needed.

Thiamylal anaesthetic therapy for febrile refractory status epilepticus in children

PURPOSE

To evaluate barbiturate anaesthetic therapy using thiamylal for febrile refractory status epilepticus (fRSE) in children.

METHODS

This was a review of a prospectively-collected database between April 2012-March 2016 for fRSE cases treated with thiamylal anaesthetic therapy in a single paediatric hospital in Japan. The sample comprised 23 children (median age, 23 months) with fRSE that underwent thiamylal anaesthetic therapy for convulsive seizures lasting longer than 60 min, sustained after intravenous administration of benzodiazepine and non-benzodiazepine anticonvulsants. The intervention comprised protocol-based thiamylal anaesthetic therapy with bolus administration. We measured the dose and time required to achieve the burst suppression pattern (BSP) on electroencephalography, seizure recurrence, death, neurological sequelae, and complications.

RESULTS

All patients except one reached the BSP. The thiamylal median dose until reaching the BSP was 27.5 mg/kg, and the median time from thiamylal administration to reaching the BSP was 109.5 min. There was one case of immediate treatment failure and one of withdrawal seizure, but no breakthrough seizure. No deaths occurred during treatment, and neurological sequelae occurred in four cases (17%). Vasopressors were administered in all cases. Other complications included 11 cases of pneumonia and one of enterocolitis.

CONCLUSION

We revealed the time and dose required to reach the BSP with thiamylal anaesthetic therapy using bolus administration in children. Our results suggested that reaching the BSP with bolus administration requires markedly less time than without bolus administration, rarely causes seizure recurrence in paediatric fRSE, and causes haemodynamic dysfunction and infections as often as observed without bolus administration.

Status epilepticus - time is brain and treatment considerations

PURPOSE OF REVIEW

Status epilepticus is a neurological emergency associated with high morbidity and mortality. There is a lack of robust data to guide the management of this neurological emergency beyond the initial treatment. This review examines recent literature on treatment considerations including the choice of continuous anesthetics or adjunctive anticonvulsant, the cause of the status epilepticus, and use of nonpharmacologic therapies.

RECENT FINDINGS

Status epilepticus remains undertreated and mortality persists to be unchanged over the past 30 years. New anticonvulsant choices, such as levetiracetam and lacosamide have been explored as alternative emergent therapies. Anecdotal reports on the use of other generation anticonvulsants and nonpharmacologic therapies for the treatment of refractory and super-refractory status epilepticus have been described.Finally, recent evidence has examined etiology-guided management of status epilepticus in certain patient populations, such as immune-mediated, paraneoplastic or infectious encephalitis and anoxic brain injury.

SUMMARY

Randomized clinical trials are needed to determine the role for newer generation anticonvulsants and nonpharmacologic modalities for the treatment of epilepticus remains and evaluate the long-term outcomes associated with continuous anesthetics.

Efficacy of levetiracetam, fosphenytoin, and valproate for established status epilepticus by age group (ESETT): a double-blind, responsive-adaptive, randomised controlled trial

BACKGROUND

Benzodiazepine-refractory, or established, status epilepticus is thought to be of similar pathophysiology in children and adults, but differences in underlying aetiology and pharmacodynamics might differentially affect response to therapy. In the Established Status Epilepticus Treatment Trial (ESETT) we compared the efficacy and safety of levetiracetam, fosphenytoin, and valproate in established status epilepticus, and here we describe our results after extending enrolment in children to compare outcomes in three age groups.

METHODS

In this multicentre, double-blind, response-adaptive, randomised controlled trial, we recruited patients from 58 hospital emergency departments across the USA. Patients were eligible for inclusion if they were aged 2 years or older, had been treated for a generalised convulsive seizure of longer than 5 min duration with adequate doses of benzodiazepines, and continued to have persistent or recurrent convulsions in the emergency department for at least 5 min and no more than 30 min after the last dose of benzodiazepine. Patients were randomly assigned in a response-adaptive manner, using Bayesian methods and stratified by age group (<18 years, 18-65 years, and >65 years), to levetiracetam, fosphenytoin, or valproate. All patients, investigators, study staff, and pharmacists were masked to treatment allocation. The primary outcome was absence of clinically apparent seizures with improved consciousness and without additional antiseizure medication at 1 h from start of drug infusion. The primary safety outcome was life-threatening hypotension or cardiac arrhythmia. The efficacy and safety outcomes were analysed by intention to treat. This study is registered in ClinicalTrials.gov, NCT01960075.

FINDINGS

Between Nov 3, 2015, and Dec 29, 2018, we enrolled 478 patients and 462 unique patients were included: 225 children (aged <18 years), 186 adults (18-65 years), and 51 older adults (>65 years). 175 (38%) patients were randomly assigned to levetiracetam, 142 (31%) to fosphenyltoin, and 145 (31%) were to valproate. Baseline characteristics were balanced across treatments within age groups. The primary efficacy outcome was met in those treated with levetiracetam for 52% (95% credible interval 41-62) of children, 44% (33-55) of adults, and 37% (19-59) of older adults; with fosphenytoin in 49% (38-61) of children, 46% (34-59) of adults, and 35% (17-59) of older adults; and with valproate in 52% (41-63) of children, 46% (34-58) of adults, and 47% (25-70) of older adults. No differences were detected in efficacy or primary safety outcome by drug within each age group. With the exception of endotracheal intubation in children, secondary safety outcomes did not significantly differ by drug within each age group.

INTERPRETATION

Children, adults, and older adults with established status epilepticus respond similarly to levetiracetam, fosphenytoin, and valproate, with treatment success in approximately half of patients. Any of the three drugs can be considered as a potential first-choice, second-line drug for benzodiazepine-refractory status epilepticus.

FUNDING

National Institute of Neurological Disorders and Stroke, National Institutes of Health.

Comparison of Phenytoin, Valproate and Levetiracetam in Pediatric Convulsive Status Epilepticus: A Randomized Double-blind Controlled Clinical Trial

OBJECTIVE

To compare the efficacy of phenytoin, valproate, and levetiracetam in the management of pediatric convulsive status epilepticus.

DESIGN

Randomized double-blind controlled clinical trial.

SETTING

Pediatric critical care division in a tertiary care institute from June, 2016 to December, 2018.

PARTICIPANTS

110 children aged three month to 12 year with convulsive status epilepticus.

INTERVENTION

Patients not responding to 0.1 mg/kg intravenous lorazepam were randomly assigned (1:1:1) to receive 20 mg/kg of phenytoin (n=35) or valproate (n=35) or levetiracetam (n=32) over 20 minutes. Patients with nonconvulsive status epilepticus, recent hemorrhage, platelet count less than 50,000 or International normalized ratio (INR) more than 2, head injury or neurosurgery in the past one-month, liver or kidney disease, suspected or known neurometabolic or mitochondrial disorders or structural malformations, and allergy to study drugs; and those who were already on any one of the study drugs for more than one month or had received one of the study drugs for current episode, were excluded.

OUTCOME MEASURE

The primary outcome was the proportion of patients that achieved control of convulsive status epilepticus at the end of 15 minutes after completion of the study drug infusion. Secondary outcomes were time to control of seizure, rate of adverse events, and the requirement of additional drugs to control seizure, length of ventilation, hospital stay, and functional status after three months (Glasgow Outcome Scale).

RESULTS

The study was stopped after the planned mid-interim analysis for futility. Intention to treat analysis was done. There was no difference in primary outcome in phenytoin (31/35, 89%), valproate (29/35, 83%), and levetiracetam (30/32, 94%) (P=0.38) groups. There were no differences between the groups for secondary outcomes. One patient in the phenytoin group had a fluid-responsive shock, and one patient in the valproate group died due to encephalopathy and refractory shock.

CONCLUSIONS

Phenytoin, valproate, and levetiracetam were equally effective in controlling pediatric convulsive status epilepticus.

Levetiracetam versus phenytoin for the treatment of established status epilepticus: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

To compare the efficacy and safety of levetiracetam and phenytoin for the treatment of established status epilepticus.

METHODS

In this systematic review, we searched Medline, Embase, and Cochrane databases from their inception with no language restrictions until May 8, 2019 and updated on February 5, 2020, for randomized controlled trials comparing the efficacy and safety of levetiracetam and phenytoin for the treatment of established status epilepticus. A Meta-analysis was conducted to calculate the risk ratio (RR) using random-effects models.

RESULTS

We identified 7 trials with a total of 1028 participants. Levetiracetam was not associated with an increased rate of clinical seizure cessation within 60 min compared with phenytoin (RR, 1.02; 95 %CI, 0.92-1.13; I² = 3%; 60.0 % [309/515] vs 59.3 % [275/463];12 more events [95 % CI, -48 to 77] per 1000 participants; moderate-quality evidence). Results were similar in the subgroup analysis of adults and children. The sample size met the optimum size in trial sequential analysis. There were also no statistically significant effects on good functional outcome (RR, 1.05; 95 % CI, 0.90-1.23), admission to critical care (RR, 1.09; 95 % CI, 0.95-1.24), or all-cause mortality (RR, 1.09; 95 % CI, 0.55-2.16).

CONCLUSIONS

Moderate-quality evidence suggested that levetiracetam was not significantly superior to phenytoin in seizure cessation in patients with established status epilepticus.

Neuroanesthesiology Update

This review is intended to provide a summary of the literature pertaining to the perioperative care of neurosurgical patients and patients with neurological diseases. General topics addressed in this review include general neurosurgical considerations, stroke, neurological monitoring, and perioperative disorders of cognitive function.

Status Epilepticus: The Slow and Agonizing Death of Phenytoin

Since its introduction in 1950, phenytoin (PHT) has been the premier parenteral anticonvulsant used in the management of generalized convulsive status epileptics (GCSE) that is refractory to benzodiazepines. Without question, its arrival was vital to the care of patients with acute seizures and was a welcomed alternative to paraldehyde and phenobarbital. However, after more than half a century of use, there continues to be insufficient evidence-based data to support its efficacy over other anticonvulsants as a first-line agent in pediatric or adult patients with GCSE. This coupled with its narrow mechanism of action, complex pharmacokinetics and pharmacogenomics, drug-drug interactions, unique adverse effects, and formulation issues that make administration difficult mandates that PHT be replaced by safer and superiorly effective anticonvulsants for the treatment of GCSE when benzodiazepines are ineffective. We believe that levetiracetam should become the preferred agent for seizures unresponsive to or recurring after treatment with a benzodiazepine as it is at least equally effective to PHT and has several important advantages. PHT has overstayed its welcome and it is simply time for it to exit the realm of acute seizure management as a first-line agent for benzodiazepine-refractory GCSE.

Rapidity of CNS Effect on Photoparoxysmal Response for Brivaracetam vs. Levetiracetam: A Randomized, Double-blind, Crossover Trial in Photosensitive Epilepsy Patients

INTRODUCTION

Both levetiracetam (LEV) and brivaracetam (BRV) eliminate the electroencephalogram photoparoxysmal response (PPR) in the human phase IIa photosensitivity model of epilepsy. The physiochemical properties of BRV differ from those of LEV, having higher potency and lipophilicity plus 10- to 15-fold greater affinity for synaptic vesicle glycoprotein 2A.

OBJECTIVE

We compared the rapidity of the effects of both drugs in the central nervous system (CNS) of patients with photosensitive epilepsy using time to PPR elimination post-intravenous infusion as a pharmacodynamic endpoint.

METHODS

Using a randomized, double-blind, two-period, balanced, crossover design, we tested patients with photosensitive epilepsy with equipotent milligram doses of intravenous LEV 1500 mg versus BRV 100 mg post-15-min intravenous infusion (part 1) and post-5-min intravenous infusion (part 2, same doses). Eight patients per part were deemed sufficient with 80% power to determine a 70% reduction for intravenous BRV:LEV intrapatient time ratio to PPR elimination, with a 0.05 two-sided significance level. Plasma antiseizure medicine concentrations were measured using liquid chromatography/mass spectrometry.

RESULTS

Nine patients [six women; mean age 27.8 years (range 18-42)] completed the study; seven of these participated in both parts 1 and 2. In 31 of 32 instances, patients experienced PPR elimination. In mixed-effects model time analysis, BRV eliminated PPRs more quickly than did LEV (median 2 vs. 7.5 min, respectively). However, no statistically significant difference in BRV:LEV time ratio to PPR elimination was observed for two of our multiple primary outcomes: for the 15-min infusion alone (p = 0.22) or the 5-min infusion alone (p = 0.11). However, BRV was faster when we excluded an outlier patient in part 1 (p = 0.0016). For our remaining primary outcome, parts 1 and 2 data combined, the median intrapatient BRV:LEV time ratio was 0.39 [95% confidence interval (CI) 0.16-0.91], i.e., PPR elimination was 61% faster with BRV, p = 0.039. PPR was completely eliminated in ≤ 2 min in 11 patients with BRV and in four patients with LEV. No period or carryover effects were seen. No serious or severe adverse effects occurred. At PPR elimination (n = 16), median plasma [BRV] was 250 ng/mL (range 30-4100) and median plasma [LEV] was 28.35 μg/mL (range 1-86.7).

CONCLUSION

Outcome studies directly comparing LEV and BRV are needed to define the clinical utility of the response with BRV, which was several minutes faster than that with LEV.

CLINICAL TRIALS

ClinTrials.gov Identifier = NCT03580707; registered 07-09-18.

Infant with status epilepticus secondary to systemic lidocaine toxicity from topical application

A previously healthy 11-month-old infant presented to the emergency department in status epilepticus. There was no clear trigger of her seizure activity which resolved with benzodiazepines and fosphenytoin. On further review, her parents disclosed that she had been prescribed topical 4% lidocaine cream for a groin rash and was ultimately diagnosed with lidocaine toxicity in the emergency department. She was monitored in the intensive care unit without cardiovascular abnormalities or recurrence of seizure activity. Emergency medicine providers must maintain a broader differential of status epileptics and be able to recognise and manage potential complications from systemic lidocaine toxicity.

Pharmacotherapy for Pediatric Convulsive Status Epilepticus

Convulsive status epilepticus (CSE) is one of the most common pediatric neurological emergencies. Ongoing seizure activity is a dynamic process and may be associated with progressive impairment of gamma-aminobutyric acid (GABA)-mediated inhibition due to rapid internalization of GABA_A receptors. Further hyperexcitability may be caused by AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) and NMDA (N-methyl-D-aspartic acid) receptors moving from subsynaptic sites to the synaptic membrane. Receptor trafficking during prolonged seizures may contribute to difficulties treating seizures of longer duration and may provide some of the pathophysiological underpinnings of established and refractory SE (RSE). Simultaneously, a practice change toward more rapid initiation of first-line benzodiazepine (BZD) treatment and faster escalation to second-line non-BZD treatment for established SE is in progress. Early administration of the recommended BZD dose is suggested. For second-line treatment, non-BZD anti-seizure medications (ASMs) include valproate, fosphenytoin, or levetiracetam, among others, and at this point there is no clear evidence that any one of these options is better than the others. If seizures continue after second-line ASMs, RSE is manifested. RSE treatment consists of bolus doses and titration of continuous infusions under continuous electro-encephalography (EEG) guidance until electrographic seizure cessation or burst-suppression. Ultimately, etiological workup and related treatment of CSE, including broad spectrum immunotherapies as clinically indicated, is crucial. A potential therapeutic approach for future studies may entail consideration of interventions that may accelerate diagnosis and treatment of SE, as well as rational and early polytherapy based on synergism between ASMs by utilizing medications targeting different mechanisms of epileptogenesis and epileptogenicity.

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.).

Medical management of status epilepticus: Emergency room to intensive care unit

In convulsive status epilepticus (SE), achieving seizure control within the first 1-2 hours after onset is a significant determinant of outcome. Treatment is also more likely to work and be cost effective the earlier it is given. Initial first aid measures should be accompanied by establishing intravenous access if possible and administering thiamine and glucose if required. Calling for help will support efficient management, and also the potential for video-recording the events. This can be done as a best interests investigation to inform later management, provided adequate steps to protect data are taken. There is high quality evidence supporting the use of benzodiazepines for initial treatment. Midazolam (buccal, intranasal or intramuscular) has the most evidence where there is no intravenous access, with the practical advantages of administration outweighing the slightly slower onset of action. Either lorazepam or diazepam are suitable IV agents. Speed of administration and adequate initial dosing are probably more important than choice of drug. Although only phenytoin (and its prodrug fosphenytoin) and phenobarbitone are licensed for established SE, a now considerable body of evidence and international consensus supports the utility of both levetiracetam and valproate as options in established status. Both also have the advantage of being well tolerated as maintenance treatment, and possibly a lower risk of serious adverse events. Two adequately powered randomized open studies in children have recently reported, supporting the use of levetiracetam as an alterantive to phenytoin. The results of a large double blind study also including valproate are also imminent, and together likely to change practice in benzodiazepine-resistant SE.

Electroencephalographic seizures in critically ill children: Management and adverse events

OBJECTIVE

Guidelines recommend that encephalopathic critically ill children undergo continuous electroencephalographic (CEEG) monitoring for electrographic seizure (ES) identification and management. However, limited data exist on antiseizure medication (ASM) safety for ES treatment in critically ill children.

METHODS

We performed a single-center prospective observational study of encephalopathic critically ill children undergoing CEEG. Clinical and EEG features and ASM utilization patterns were evaluated. We determined the incidence, types, and risk factors for adverse events associated with ASM administration.

RESULTS

A total of 472 consecutive critically ill children undergoing CEEG were enrolled. ES occurred in 131 children (28%). Clinicians administered ASM to 108 children with ES (82%). ES terminated after the initial ASM in 38% of patients who received one ASM, after the second ASM in 35% of patients who received two ASMs, after the third ASM in 50% of patients who received three ASMs, and after the fourth ASM in 53% of patients who received four ASMs. Thirty patients (28%) received anesthetic infusions for ES management. Adverse events occurred in 18 patients (17%). Adverse effects were expected and resolved in all patients, and they were generally serious (in 15 patients) and definitely related (in 12 patients). Adverse events were rare in patients with acute symptomatic seizures requiring only one to two ASMs for treatment, but were more common in children with epilepsy, ictal-interictal continuum EEG patterns, or patients requiring more extensive ASM management.

SIGNIFICANCE

ES ceased after one ASM in only 38% of critically ill children but ceased after two ASMs in 73% of critically ill children. Thus, ES management was often accomplished with readily available medications, but optimization of multistep ES management strategies might be beneficial. Adverse events were rare and manageable in children with acute symptomatic seizures requiring only one to two ASMs for treatment. Future studies are needed to determine whether management of acute symptomatic ES improves neurobehavioral outcomes.