The established status epilepticus trial 2013

Evaluation of intravenous lorazepam dosing strategies and the incidence of refractory status epilepticus

INTRODUCTION

Status epilepticus (SE) is a neurological emergency associated with high mortality if not identified and treated promptly. For the emergent treatment of SE, the recommended intravenous (IV) lorazepam dose is 0.1 mg/kg/dose, up to a maximum of 4 mg. It has been shown that lorazepam is commonly under dosed in SE, but there is conflicting data on whether this has a negative impact on patient outcomes. This study assessed any dose less than 4 mg to help identify the effects of under dosing lorazepam in SE.

METHODS

This was a retrospective cohort study of patients admitted to a quaternary health system between October 1, 2017 and September 30, 2019 that experienced SE and were initially treated with IV lorazepam. Patients were divided into two cohorts, less than 4 mg or 4 mg, based on the initial one-time dose of lorazepam received. The primary outcome was the proportion of patients that progressed to refractory status epilepticus (RSE) that received an initial IV lorazepam dose of 4 mg compared to less than 4 mg for the treatment of SE. Secondary outcomes evaluated include length of stay, mortality, time in SE, number of seizures, cumulative lorazepam dose prior to urgent therapy, number of lorazepam doses prior to urgent therapy, time to urgent therapy, appropriately dosed urgent therapy, and number of antiepileptic drugs given in SE.

RESULTS

One hundred twenty patients were included in this study (107 patients received less than 4 mg and 13 patients received 4 mg). All patients included in the study were greater than 40 kg. The primary outcome of progression to RSE was observed in a significantly greater proportion of patients in the less than 4 mg group compared to the 4 mg group (93 [87%] vs. 8 [62%], p = 0.03). There was no difference in hospital or intensive care unit length of stay. However, there was an increased rate of in-hospital mortality in patients who received 4 mg compared to less than 4 mg (5 [39%] vs. 12[11%], p = 0.02).

DISCUSSION

The majority of patients in the study received less than the recommended dose of IV lorazepam for SE. Patients who received less than 4 mg experienced an increased progression to RSE, which supports current guideline recommended dosing. While there was an increased rate of mortality in patients who received 4 mg compared to less than 4 mg, time in SE was prolonged in the patient population and severity of illness was only available for a limited number of patients included.

Refractory and Super-refractory Status Epilepticus

Context

Refractory status epilepticus (RSE) and super-refractory status epilepticus (SRSE) are neurological emergencies with considerable mortality and morbidity. In this paper, we provide an overview of causes, evaluation, treatment, and consequences of RSE and SRSE, reflecting the lack of high-quality evidence to inform therapeutic approach.

Sources

This is a narrative review based on personal practice and experience. Nevertheless, we searched MEDLINE (using PubMed and OvidSP vendors) and Cochrane central register of controlled trials, using appropriate keywords to incorporate recent evidence.

Results

Refractory status epilepticus is commonly defined as an acute convulsive seizure that fails to respond to two or more anti-seizure medications including at least one nonbenzodiazepine drug. Super-refractory status epilepticus is a status epilepticus that continues for ≥24 hours despite anesthetic treatment, or recurs on an attempted wean of the anesthetic regimen. Both can occur in patients known to have epilepsy or de novo, with increasing recognition of autoimmune and genetic causes. Electroencephalography monitoring is essential to monitor treatment response in refractory/super-refractory status epilepticus, and to diagnose non-convulsive status epilepticus. The mainstay of treatment for these disorders includes anesthetic infusions, primarily midazolam, ketamine, and pentobarbital. Dietary, immunological, and surgical treatments are viable in selected patients. Management is challenging due to multiple acute complications and long-term adverse consequences.

Conclusions

We have provided a synopsis of best practices for diagnosis and management of refractory/superrefractory status epilepticus and highlighted the lack of sufficient high-quality evidence to drive decision making, ending with a brief foray into avenues for future research.

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.

Antiseizure medications in critical care: an update

PURPOSE OF REVIEW

Seizures and status epilepticus are very common diagnoses in the critically ill patient and are associated with significant morbidity and mortality. There is an abundance of research on the utility of antiseizure medications in this setting, but limited randomized-controlled trials to guide the selection of medications in these patients. This review examines the current guidelines and treatment strategies for status epilepticus and provides an update on newer antiseizure medications in the critical care settings.

RECENT FINDINGS

Time is brain applies to status epilepticus, with delays in treatment corresponding with worsened outcomes. Establishing standardized treatment protocols within a health system, including prehospital treatment, may lead to improved outcomes. Once refractory status epilepticus is established, continuous deep sedation with intravenous anesthetic agents should be effective. In cases, which prove highly refractory, novel approaches should be considered, with recent data suggesting multiple recently approved antiseizure medications, appropriate therapeutic options, as well as novel approaches to upregulate extrasynaptic γ-aminobutyric acid channels with brexanolone.

SUMMARY

Although there are many new treatments to consider for seizures and status epilepticus in the critically ill patient, the most important predictor of outcome may be rapid diagnosis and treatment. There are multiple new and established medications that can be considered in the treatment of these patients once status epilepticus has become refractory, and a multidrug regimen will often be necessary.

Big data in status epilepticus

Status epilepticus care and treatment are already being touched by the revolution in data science. New approaches designed to leverage the tremendous potential of "big data" in the clinical sphere are enabling researchers and clinicians to extract information from sources such as administrative claims data, the electronic medical health record, and continuous physiologic monitoring data streams. Algorithmic methods of data extraction also offer potential to fuse multimodal data (including text-based documentation, imaging data, and time-series data) to improve patient assessment and stratification beyond the manual capabilities of individual physicians. Still, the potential of data science to impact the diagnosis, treatment, and minute-to-minute care of patients with status epilepticus is only starting to be appreciated. In this brief review, we discuss how data science is impacting the field and draw examples from the following three main areas: (1) analysis of insurance claims from large administrative datasets to evaluate the impact of continuous electroencephalogram (EEG) monitoring on clinical outcomes; (2) natural language processing of the electronic health record to find, classify, and stratify patients for prognostication and treatment; and (3) real-time systems for data analysis, data reduction, and multimodal data fusion to guide therapy in real time. While early, it is our hope that these examples will stimulate investigators to leverage data science, computer science, and engineering methods to improve the care and outcome of patients with status epilepticus and other neurological disorders. This article is part of the Special Issue "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures".

Lessons from the Established Status Epilepticus Treatment Trial

Convulsive status epilepticus (SE) is a relatively common emergency condition affecting individuals of all ages. The primary goal of treatment is prompt termination of seizures. Where first-line treatment with benzodiazepine has failed to achieve this, a condition known as established SE (ESE), there is uncertainty about which agent to use next. The Established Status Epilepticus Treatment Trial (ESETT) is a 3-arm (valproate (VPA), fosphenytoin (FOS), levetiracetam (LEV)), phase III, double-blind randomized comparative effectiveness study in patients aged 2 years and above with established convulsive SE. Enrollment was completed in January 2019, and the results are expected later this year. We discuss lessons learnt during the conduct of the study in relation to the following: ethical considerations; trial design and practical implementation in emergency settings, including pediatric and adult populations; quality assurance; and outcome determination where treating emergency clinicians may lack specialist expertise. We consider that the ESETT is already informing both clinical practice and future trial design. This article is part of the Special Issue "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures".

Status epilepticus in pregnancy - Can we frame a uniform treatment protocol?

BACKGROUND

There is lack of uniform treatment protocol for status epilepticus (SE) in pregnancy, with majority of data being limited to individual cases or case series. Devising a uniform treatment protocol will facilitate prompt control of SE in pregnancy and reduce adverse maternal and fetal outcomes.

METHODS

Literature search was done in various databases including PubMed, CINAHL, EMBASE, TRIP, and the gray literature, including relevant organizational websites, for the topics "Status Epilepticus" and "Pregnancy". English language original research articles, case reports, and systematic reviews that were published in the last 18 years (2000-2018) and addressed SE in relation to pregnancy (i.e., antepartum, labor, or postpartum) were considered for inclusion.

RESULTS

Over the past 15 years, a total of seven articles reporting 29 cases of SE related to pregnancy, satisfying the inclusion criteria were analyzed. The most common cause of SE was posterior reversible encephalopathy syndrome (PRES)/reversible cerebral vasoconstriction syndrome (RCVS) spectrum (n = 11, 38%), followed by cortical venous sinus thrombosis (CVT) and autoimmune encephalitis (n = 5, 17%). Twenty-three out of 29 cases (79%) had good maternal outcomes in terms of recovery to baseline. Seventeen fetuses (58%) were delivered at term and seven at preterm (2.4%). First-line agent used was lorazepam in 15 patients (52%) and midazolam in two patients (7%). The most common antiepileptic drug (AED) and anesthesia used for treatment of SE and refractory SE were phenytoin/fosphenytoin (n = 21, 72%) and midazolam (n = 12, 52%), respectively. In all cases due to eclampsia (n = 5), magnesium sulfate was the preferred first-line drug.

CONCLUSION

Management of SE in pregnancy is influenced by etiology of SE and duration of pregnancy. It carries a good prognosis if detected early and treated appropriately. Large-scale multicentric studies are warranted for formulating definite guidelines for management of SE in pregnancy. This article is part of the Special Issue "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures".

Levetiracetam versus phenytoin in children with status epilepticus

Background:

To compare the efficacy and safety of intravenous levetiracetam and phenytoin in status epilepticus.

Methodology:

A prospective, randomized controlled, nonblinded study was conducted in children 1 month to 12 years of age with active seizure and with status epilepticus. A total of 104 children were randomly allocated to either group 1 (levetiracetam) or group 2 (phenytoin) on the basis of computer-generated random number table. Children already on antiepileptic drugs, very sick children with shock, impending respiratory failure, or head injury, and children hypersensitive to phenytoin or levetiracetam were excluded. Data analysis was done by IBM SPSS statistics.

Results:

The mean age was 4.09 years with a male preponderance with the most common type of seizure being generalized type (74%). The seizures were controlled in all 104 patients initially within 40 min. Seizure control for 24 h was significantly better in group 1 (96%) when compared with group 2 (59.6%) (P = 0.0001). Minibolus of drug was given in 28.8% in group 1 and 46.2% in group 2 (P = 0.068). The seizure recurrence in groups 1 and 2 in the first hour was 1.9% and 5.8%, respectively (P = 0.61), whereas the recurrence between 1 and 24 h was significantly more in group 1 (34.6%) when compared with group 2 (3.8%) (P = 0.0001). The mean time to control seizure was comparable between both the groups (P = 0.71). There was no significant adverse effect in both the groups.

Conclusion:

Levetiracetam is more effective than phenytoin for seizure control for 24 h in children with status epilepticus, and it is safe and effective as a second-line therapy.

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.

Association of Time to Treatment With Short-term Outcomes for Pediatric Patients With Refractory Convulsive Status Epilepticus

Importance

Treatment delay for seizures can lead to longer seizure duration. Whether treatment delay is associated with major adverse outcomes, such as death, remains unknown.

Objective

To evaluate whether untimely first-line benzodiazepine treatment is associated with unfavorable short-term outcomes.

Design, Setting, and Participants

This multicenter, observational, prospective cohort study included 218 pediatric patients admitted between June 1, 2011, and July 7, 2016, into the 11 tertiary hospitals in the United States within the Pediatric Status Epilepticus Research Group. Patients, ranging in age from 1 month to 21 years, with refractory convulsive status epilepticus (RCSE) that did not stop after the administration of at least 2 antiseizure medications were included. Patients were divided into 2 cohorts: those who received the first-line benzodiazepine treatment in less than 10 minutes and those who received it 10 or more minutes after seizure onset (untimely). Data were collected and analyzed from June 1, 2011, to July 7, 2016.

Main Outcomes and Measures

The primary outcome was death during the related hospital admission. The secondary outcome was the need for continuous infusion for seizure termination. Multivariate analysis of mortality controlled for structural cause, febrile RCSE, age, and previous neurological history (including previous RCSE events). Use of continuous infusions was additionally adjusted for generalized RCSE, continuous RCSE, and 5 or more administrations of antiseizure medication.

Results

A total of 218 patients were included, among whom 116 (53.2%) were male and the median (interquartile range) age was 4.0 (1.2-9.6) years. The RCSE started in the prehospital setting for 139 patients (63.8%). Seventy-four patients (33.9%) received their first-line benzodiazepine treatment in less than 10 minutes, and 144 (66.1%) received untimely first-line benzodiazepine treatment. Multivariate analysis showed that patients who received untimely first-line benzodiazepine treatment had higher odds of death (adjusted odds ratio [AOR], 11.0; 95% CI, 1.43 to ∞; P = .02), had greater odds of receiving continuous infusion (AOR, 1.8; 95% CI, 1.01-3.36; P = .047), had longer convulsive seizure duration (AOR, 2.6; 95% CI, 1.38-4.88; P = .003), and had more frequent hypotension (AOR 2.3; 95% CI, 1.16-4.63; P = .02). In addition, the timing of the first-line benzodiazepine treatment was correlated with the timing of the second-line (95% CI, 0.64-0.95; P < .001) and third-line antiseizure medications (95% CI, 0.25-0.78; P < .001).

Conclusions and Relevance

Among pediatric patients with RCSE, an untimely first-line benzodiazepine treatment is independently associated with a higher frequency of death, use of continuous infusions, longer convulsion duration, and more frequent hypotension. Results of this study raise the question as to whether poor outcomes could, in part, be prevented by earlier administration of treatment.

Status Epilepticus, Refractory Status Epilepticus, and Super-refractory Status Epilepticus

PURPOSE OF REVIEW

Status epilepticus, refractory status epilepticus, and super-refractory status epilepticus can be life-threatening conditions. This article presents an overview of the three conditions and discusses their management and outcomes.

RECENT FINDINGS

Status epilepticus was previously defined as lasting for 30 minutes or longer but now is more often defined as lasting 5 minutes or longer. A variety of potential causes exist for status epilepticus, refractory status epilepticus, and super-refractory status epilepticus, but all three ultimately involve changes at the cellular and molecular level. Management of patients with status epilepticus generally requires several studies, with EEG of utmost importance given the pathophysiologic changes that can occur during the course of status epilepticus. Status epilepticus is treated with benzodiazepines as first-line antiepileptic drugs, followed by phenytoin, valproic acid, or levetiracetam. If status epilepticus does not resolve, these are followed by an IV anesthetic and then alternative therapies based on limited data/evidence, such as repetitive transcranial magnetic stimulation, therapeutic hypothermia, immunomodulatory agents, and the ketogenic diet. Scores have been developed to help predict the outcome of status epilepticus. Neurologic injury and outcome seem to worsen as the duration of status epilepticus increases, with outcomes generally worse in super-refractory status epilepticus compared to status epilepticus and sometimes also to refractory status epilepticus.

SUMMARY

Status epilepticus can be a life-threatening condition associated with multiple complications, including death, and can progress to refractory status epilepticus and super-refractory status epilepticus. More studies are needed to delineate the best management of these three entities.

Management of convulsive status epilepticus in children: an adapted clinical practice guideline for pediatricians in Saudi Arabia

Objective:

To increase the use of evidence-based approaches in the diagnosis, investigations and treatment of Convulsive Status Epilepticus (CSE) in children in relevant care settings.

Method:

A Clinical Practice Guideline (CPG) adaptation group was formulated at a university hospital in Riyadh. The group utilized 2 CPG validated tools including the ADAPTE method and the AGREE II instrument.

Results:

The group adapted 3 main categories of recommendations from one Source CPG. The recommendations cover; (i)first-line treatment of CSE in the community; (ii)treatment of CSE in the hospital; and (iii)refractory CSE. Implementation tools were built to enhance knowledge translation of these recommendations including a clinical algorithm, audit criteria, and a computerized provider order entry.

Conclusion:

A clinical practice guideline for the Saudi healthcare context was formulated using a guideline adaptation process to support relevant clinicians managing CSE in children.

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.

Pharmacotherapy for Refractory and Super-Refractory Status Epilepticus in Adults

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

Intravenous use of valproic acid in status epilepticus is associated with high risk of hyperammonemia

PURPOSE

The aim of the study was to examine the frequency of hyperammonemia secondary to valproic acid treatment in status epilepticus and to describe the characteristics of the patients.

METHODS

All patients with established status epilepticus during 2014 to 2016 at Ryhov County Hospital were identified in a retrospective case series. Clinical and laboratory findings were collected from electronic medical files and the Metavision database at the intensive care unit (ICU). Hyperammonemia was defined as a concentration of at least 50 μmol/L.

RESULTS

11 of 40 patients developed hyperammonemia. These patients had a significantly longer stay at the ICU (12.6 vs 2.5 days) and at the hospital (22 vs 11 days). All patients with hyperammonemia were treated at the ICU and all received antibiotics. 12 patients were treated with intravenous valproic acid outside the ICU. Hyperammonemia was not related to Body Mass Index, time to initiation of therapy or laboratory abnormalities except anemia (Hemoglobin 104 vs 122 g/l). There was no difference in mortality between groups.

CONCLUSION

The risk of hyperammonemia is almost 40% in patients receiving intravenous valproic acid in the ICU setting. The underlying mechanisms are probably either individual susceptibility or high metabolic demands. A high vigilance should be recommended. These data require further research via prospective designs in which multiple variables are controlled to explore the effects of individual factors on treatment outcome.

Update in status epilepticus

Status epilepticus (SE) is a neurological emergency that requires urgent antiepileptic therapies, and a rapid treatment of its cause. In recent years, its definition has been updated to adapt it to all types of SE; this update helps to standardise the treatment. The new definition is based on two times: point t1, after which the event will not spontaneously cease, and period t2, after which neuronal damage may appear. There are three lines of treatment: first, benzodiazepines; second, antiepileptic drugs; and third, intravenous anaesthetics. The application of the different lines of treatment raises still unanswered questions, since the prognosis also depends on the aetiology, age and duration. For this reason, different prognostic scales are being developed to help us to assess its evolution and in turn, adapt the aggressiveness of the treatment to each patient.

In Situ Simulation to Mitigate Threats to Participation in a Multicenter Clinical Trial in High-Acuity, Low-Frequency Setting

INTRODUCTION

Multicenter clinical trials of high-acuity, low-frequency emergencies are expensive and resource intensive. Current standards for trial preparation have significant limitations. Our objective is to describe our use of in situ simulation (ISS) to identify and mitigate threats to enrollment, protocol adherence, and patient safety in preparation for a multicenter clinical trial of antiepileptics for status epilepticus in the emergency department.

METHODS

This is a descriptive study of ISS conducted in the emergency department at a free-standing, academic pediatric institution. We designed two scenarios, one for an eligible and ineligible patient, to allow care teams to complete all study procedures. All study training was completed before the first ISS. Participants included physicians, nurses, patient care assistants, paramedics, research coordinators, and pharmacists. Ten-minute simulations were followed by 10-minute debriefings, led by trained facilitators using a standard template. Data on threats to enrollment, protocol adherence, and patient safety were recorded. Mitigation strategies were developed by the study team and local experts in ISS.

RESULTS

Ten of 18 planned simulations were conducted. Seven of 10 completed simulations were study eligible patients, with 73 total participants. Nine threats to enrollment and five to protocol adherence were identified. Five of 14 were also threats to patient safety. Mitigation strategies included creation of decision aid tools, targeted education during debriefings, adapting study material for use, and revision of status epilepticus treatment algorithm.

CONCLUSIONS

The addition of ISS to standard preparation for a multicenter clinical trial facilitated the identification and mitigation of threats to study participation and patient safety.

Seizures and epilepsy in the acute medical setting: presentation and management

Epileptic seizures are a common cause for presentation to acute medical services. Whether presenting with an isolated, unprovoked seizure or with status epilepticus, a good understanding of seizures and their mimics ensures appropriate investigation and treatment. This article describes the practical aspects of the management of patients presenting with seizures to the emergency department or the acute medical unit.

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.

The 'top 100' drugs and classes in England: an updated 'starter formulary' for trainee prescribers

AIMS

Prescribing is a complex skill required of doctors and, increasingly, other healthcare professionals. Use of a personal formulary can help to develop this skill. In 2006-9, we developed a core list of the 100 most commonly prescribed drugs. Our aim in the present study was to update this 'starter formulary' to ensure its continued relevance for prescriber training.

METHODS

We analysed large contemporary primary and secondary care datasets to identify the most frequently prescribed medicinal products. Items were classified into natural groups, broadly following their British National Formulary classification. The resulting drug groups were included in the core list if they comprised ≥0.1% prescriptions in both settings or ≥0.2-0.3% prescriptions in one setting. Drugs from emergency guidelines that did not qualify by prescribing frequency completed the list.

RESULTS

Over 1 billion primary care items and approximately 1.8 million secondary care prescriptions were analysed. The updated list comprises 81 drug groups commonly prescribed in both settings; six from primary care; seven from secondary care; and six from emergency guidelines. Eighty-eight per cent of the formulary was unchanged. Notable changes include entry of newer anti-epileptics and dipeptidyl peptidase-4 inhibitors and exit of phenytoin and thiazolidinediones.

CONCLUSIONS

The relative stability of the core drug list over 9 years and the current update ensure that learning based on this list remains relevant to practice. Trainee prescribers may be encouraged to use this 'starter formulary' to develop a sound basis of prescribing knowledge and skills that they can subsequently apply more widely.

Why we prefer levetiracetam over phenytoin for treatment of status epilepticus

Over last fifty years, intravenous (iv) phenytoin (PHT) loading dose has been the treatment of choice for patients with benzodiazepine-resistant convulsive status epilepticus and several guidelines recommended this treatment regimen with simultaneous iv diazepam. Clinical studies have never shown a better efficacy of PHT over other antiepileptic drugs. In addition, iv PHT loading dose is a complex and time-consuming procedure which may expose patients to several risks, such as local cutaneous reactions (purple glove syndrome), severe hypotension and cardiac arrhythmias up to ventricular fibrillation and death, and increased risk of severe allergic reactions. A further disadvantage of PHT is that it is a strong enzymatic inducer and it may make ineffective several drugs that need to be used simultaneously with antiepileptic treatment. In patients with a benzodiazepine-resistant status epilepticus, we suggest iv administration of levetiracetam as soon as possible. If levetiracetam would be ineffective, a further antiepileptic drug among those currently available for iv use (valproate, lacosamide, or phenytoin) can be added before starting third line treatment.

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.

A critical appraisal of randomized controlled trials on intravenous phenytoin in convulsive status epilepticus

Since the 1970s, intravenous (IV) phenytoin (PHT) has traditionally been used as second-stage treatment for convulsive status epilepticus (SE) after failure of benzodiazepines. The aim of this review was to critically assess the evidence supporting the use of IV PHT as treatment of convulsive SE in patients of any age. In particular, we critically appraised the results of randomized controlled trials (RCTs) evaluating IV PHT as treatment of convulsive SE. A systematic search of the literature was carried out to identify RCTs evaluating IV PHT as treatment of convulsive SE in patients of any age. Eight RCTs (544 patients allocated to IV PHT) were included. The included studies differed in almost every single characteristic considered. Six RCTs (472 patients) used IV PHT without demonstrating refractoriness of SE to benzodiazepines. Only two RCTs (72 patients) used IV PHT as second-line treatment for benzodiazepine-resistant convulsive SE. Overall, most evidence from RCTs supports the use of IV PHT immediately after IV diazepam, even if seizures have not recurred. The recommendation derived from RCTs supporting the use of IV PHT as second-line treatment in benzodiazepine-resistant convulsive SE is weak. This is emblematic of the lack of robust evidence from large RCTs to inform clinical practice on how to treat SE after failure of first-line drugs. IV PHT given immediately after first-line benzodiazepines could prolong their short antiepileptic effect and prevent seizure recurrence.

Electroencephalography and behavior patterns during experimental status epilepticus

OBJECTIVE

To characterize the evolution of behavioral and electrographic seizures in an experimental electrical stimulation-based model of status epilepticus (SE) in C57Bl/6 mice, and to relate SE to various outcomes, including death and epileptogenesis.

METHODS

SE was induced by continuous hippocampal stimulation and was evaluated by review of electroencephalographic recordings, spectral display, and behavior.

RESULTS

Seizures were initially locked to the electrical trains but later became independent of them. Following the end of stimulation, autonomous seizures continued for >5 minutes in 85% of the animals. There was ongoing 2-3-Hz rhythmic, high-amplitude, slow spike-wave discharges (HASDs) associated with purposeless, repetitive, continuously circling and exploratory behavior. There were high-amplitude fast discharges (HAFDs) associated with worsening of behavioral seizures that were interspersed with the ongoing HASDs. Death during SE occurred in 23% of the animals, and it was preceded by a stage 5 behavioral seizure. In the waning stage of SE, severe seizures and HAFDs dissipated, HASDs slowed down, and normal behavior was restored in most animals. Epilepsy developed in 33% of the animals monitored after SE.

SIGNIFICANCE

The electrical stimulation model of SE can be used to study mechanisms of SE and its adverse consequences, including death and epileptogenesis.

Flupirtine and diazepam combination terminates established status epilepticus: results in three rodent models

Objective

Status epilepticus (SE) is a neurological emergency requiring rapid termination of seizures. New treatment choices are needed for benzodiazepine-refractory SE or established SE (ESE). Previous studies have demonstrated that the potassium-channel opener flupirtine terminates seizures in neonatal animals. However, its effectiveness in adult ESE has not been tested. We tested whether flupirtine alone or in combination with the benzodiazepine diazepam would terminate ESE in three animal models.

Methods

SE was induced by administration of lithium followed by pilocarpine, by electrical stimulation of the hippocampus or by diisopropylfluorophosphate (DFP) administration. Seizures were assessed by EEG recorded from the hippocampus and cortex.

Results

Flupirtine alone did not terminate ESE within 60 min of administration in any of the three models of ESE. A combination of flupirtine and diazepam terminated ESE within 60 min in all the three models. The drug combination shortened the duration of ESE in all three models. Drug responsiveness was distinct between each model.

Conclusion

A combination of the potassium channel opener flupirtine and diazepam is a potential therapy for ESE.

The life cycles of six multi-center adaptive clinical trials focused on neurological emergencies developed for the Advancing Regulatory Science initiative of the National Institutes of Health and US Food and Drug Administration: Case studies from the Adaptive Designs Accelerating Promising Treatments Into Trials Project

OBJECTIVES

Clinical trials are complicated, expensive, time-consuming, and frequently do not lead to discoveries that improve the health of patients with disease. Adaptive clinical trials have emerged as a methodology to provide more flexibility in design elements to better answer scientific questions regarding whether new treatments are efficacious. Limited observational data exist that describe the complex process of designing adaptive clinical trials. To address these issues, the Adaptive Designs Accelerating Promising Treatments Into Trials project developed six, tailored, flexible, adaptive, phase-III clinical trials for neurological emergencies, and investigators prospectively monitored and observed the processes. The objective of this work is to describe the adaptive design development process, the final design, and the current status of the adaptive trial designs that were developed.

METHODS

To observe and reflect upon the trial development process, we employed a rich, mixed methods evaluation that combined quantitative data from visual analog scale to assess attitudes about adaptive trials, along with in-depth qualitative data about the development process gathered from observations.

RESULTS

The Adaptive Designs Accelerating Promising Treatments Into Trials team developed six adaptive clinical trial designs. Across the six designs, 53 attitude surveys were completed at baseline and after the trial planning process completed. Compared to baseline, the participants believed significantly more strongly that the adaptive designs would be accepted by National Institutes of Health review panels and non-researcher clinicians. In addition, after the trial planning process, the participants more strongly believed that the adaptive design would meet the scientific and medical goals of the studies.

CONCLUSION

Introducing the adaptive design at early conceptualization proved critical to successful adoption and implementation of that trial. Involving key stakeholders from several scientific domains early in the process appears to be associated with improved attitudes towards adaptive designs over the life cycle of clinical trial development.

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.

Timing is everything: Where status epilepticus treatment fails

Status epilepticus is an emergency; however, prompt treatment of patients with status epilepticus is challenging. Clinical trials, such as the ESETT (Established Status Epilepticus Treatment Trial), compare effectiveness of antiepileptic medications, and rigorous examination of effectiveness of care delivery is similarly warranted. We reviewed the medical literature on observed deviations from guidelines, clinical significance, and initiatives to improve timely treatment. We found pervasive, substantial gaps between recommended and "real-world" practice with regard to timing, dosing, and sequence of antiepileptic therapy. Applying quality improvement methodology at the institutional level can increase adherence to guidelines and may improve patient outcomes. Ann Neurol 2017;82:155-165.

Review article: Paediatric status epilepticus in the pre-hospital setting: An update

Paediatric status epilepticus (SE) is a medical emergency and a common critical condition confronting pre-hospital providers. Management in the pre-hospital environment is challenging but considered extremely important as a potentially modifiable factor on outcome. Recent data from multicentre clinical trials, quality observational studies and consensus documents have influenced management in this area, and is important to both pre-hospital providers and emergency physicians. The objective of this review was to: (i) present an overview of the available evidence relevant to pre-hospital care of paediatric SE; and (ii) assess the current pre-hospital practice guidelines in Australia and New Zealand. The review outlines current definitions and guidelines of SE management, regional variability in pre-hospital protocols within Australasia and aspects of pre-hospital care that could potentially be improved. Contemporary data is required to determine current practice in our setting. It is important that paediatric neurologists, emergency physicians and pre-hospital care providers are all engaged in future endeavours to improve clinical care and knowledge translation efforts for this patient group.

Randomized, Multicenter Trial of ARTSS-2 (Argatroban With Recombinant Tissue Plasminogen Activator for Acute Stroke)

BACKGROUND AND PURPOSE

We conducted a randomized exploratory study to assess safety and the probability of a favorable outcome with adjunctive argatroban, a direct thrombin-inhibitor, administered to recombinant tissue-type plasminogen activator (r-tPA)-treated ischemic stroke patients.

METHODS

Patients treated with standard-dose r-tPA, not receiving endovascular therapy, were randomized to receive no argatroban or argatroban (100 μg/kg bolus) followed by infusion of either 1 (low dose) or 3 μg/kg per minute (high dose) for 48 hours. Safety was incidence of symptomatic intracerebral hemorrhage. Probability of clinical benefit (modified Rankin Scale score 0-1 at 90 days) was estimated using a conservative Bayesian Poisson model (neutral prior probability centered at relative risk, 1.0 and 95% prior intervals, 0.33-3.0).

RESULTS

Ninety patients were randomized: 29 to r-tPA alone, 30 to r-tPA+low-dose argatroban, and 31 to r-tPA+high-dose argatroban. Rates of symptomatic intracerebral hemorrhage were similar among control, low-dose, and high-dose arms: 3/29 (10%), 4/30 (13%), and 2/31 (7%), respectively. At 90 days, 6 (21%) r-tPA alone, 9 (30%) low-dose, and 10 (32%) high-dose patients were with modified Rankin Scale score 0 to 1. The relative risks (95% credible interval) for modified Rankin Scale score 0 to 1 with low, high, and either low or high dose argatroban were 1.17 (0.57-2.37), 1.27 (0.63-2.53), and 1.34 (0.68-2.76), respectively. The probability that adjunctive argatroban was superior to r-tPA alone was 67%, 74%, and 79% for low, high, and low or high dose, respectively.

CONCLUSIONS

In patients treated with r-tPA, adjunctive argatroban was not associated with increased risk of symptomatic intracerebral hemorrhage and provides evidence that a definitive effectiveness trial is indicated.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique Identifier: NCT01464788.

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.

A conceptual model for the development process of confirmatory adaptive clinical trials within an emergency research network

BACKGROUND

Adaptive clinical trials use accumulating data from enrolled subjects to alter trial conduct in pre-specified ways based on quantitative decision rules. In this research, we sought to characterize the perspectives of key stakeholders during the development process of confirmatory-phase adaptive clinical trials within an emergency clinical trials network and to build a model to guide future development of adaptive clinical trials.

METHODS

We used an ethnographic, qualitative approach to evaluate key stakeholders' views about the adaptive clinical trial development process. Stakeholders participated in a series of multidisciplinary meetings during the development of five adaptive clinical trials and completed a Strengths-Weaknesses-Opportunities-Threats questionnaire. In the analysis, we elucidated overarching themes across the stakeholders' responses to develop a conceptual model.

RESULTS

Four major overarching themes emerged during the analysis of stakeholders' responses to questioning: the perceived statistical complexity of adaptive clinical trials and the roles of collaboration, communication, and time during the development process. Frequent and open communication and collaboration were viewed by stakeholders as critical during the development process, as were the careful management of time and logistical issues related to the complexity of planning adaptive clinical trials.

CONCLUSION

The Adaptive Design Development Model illustrates how statistical complexity, time, communication, and collaboration are moderating factors in the adaptive design development process. The intensity and iterative nature of this process underscores the need for funding mechanisms for the development of novel trial proposals in academic settings.

Recent advances in epilepsy

This paper reviews advances in epilepsy in recent years with an emphasis on therapeutics and underlying mechanisms, including status epilepticus, drug and surgical treatments. Lessons from rarer epilepsies regarding the relationship between epilepsy type, mechanisms and choice of antiepileptic drugs (AED) are explored and data regarding AED use in pregnancy are reviewed. Concepts evolving towards a move from treating seizures to treating epilepsy are discussed, both in terms of the mechanisms of epileptogenesis, and in terms of epilepsy's broader comorbidity, especially depression.

Neurosteroid-sensitive δ-GABAA receptors: A role in epileptogenesis?

OBJECTIVE

We determined the role of the neurosteroid-sensitive δ subunit-containing γ-aminobutyric acid A receptors (δ-GABARs) in epileptogenesis.

METHODS

Status epilepticus (SE) was induced via lithium pilocarpine in adult rats, and seizures were assessed by continuous video-electroencephalography (EEG) monitoring. Finasteride was administered to inhibit neurosteroid synthesis. The total and surface protein expression of hippocampal δ, α4, and γ2 GABAR subunits was studied using biotinylation assays and Western blotting. Neurosteroid potentiation of the tonic currents of dentate granule cells (DGCs) was measured by whole-cell patch-clamp technique. Finally, the effects of inhibiting N-methyl-d-aspartate receptors (NMDARs) during SE on the long-term plasticity of δ-GABARs, neurosteroid-induced modulation of tonic current, and epileptogenesis were studied.

RESULTS

The inhibition of neurosteroid synthesis 4 days after SE triggered acute seizures and accelerated the onset of chronic recurrent spontaneous seizures (epilepsy). The down-regulation of neurosteroid-sensitive δ-GABARs occurred prior to the onset of epilepsy, whereas an increased expression of the γ2-GABAR subunits occurred after seizure onset. MK801 blockade of NMDARs during SE preserved the expression of neurosteroid-sensitive δ-GABARs. NMDAR blockade during SE also prevented the onset of spontaneous seizures.

SIGNIFICANCE

Changes in neurosteroid-sensitive δ-GABAR expression correlated temporally with epileptogenesis. These findings raise the possibility that δ-GABAR plasticity may play a role in epileptogenesis.

Management of status epilepticus

Status epilepticus is a neurologic and medical emergency manifested by prolonged seizure activity or multiple seizures without return to baseline. It is associated with substantial medical cost, morbidity, and mortality. There is a spectrum of severity dependent on the type of seizure, underlying pathology, comorbidities, and appropriate and timely medical management. This chapter discusses the evolving definitions of status epilepticus and multiple patient and clinical factors which influence outcome. The pathophysiology of status epilepticus is reviewed to provide a better understanding of the mechanisms which contribute to status epilepticus, as well as the potential long-term effects. The clinical presentations of different types of status epilepticus in adults are discussed, with emphasis on the hospital course and management of the most dangerous type, generalized convulsive status epilepticus. Strategies for the evaluation and management of status epilepticus are provided based on available evidence from clinical trials and recommendations from the Neurocritical Care Society and the European Federation of Neurological Societies.

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

PURPOSE

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

METHOD

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

RESULTS

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

CONCLUSION

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

Direct and indirect comparison meta-analysis of levetiracetam versus phenytoin or valproate for convulsive status epilepticus

AIM

The aim of this study was to conduct a meta-analysis of published studies to directly compare intravenous (IV) levetiracetam (LEV) with IV phenytoin (PHT) or IV valproate (VPA) as second-line treatment of status epilepticus (SE), to indirectly compare intravenous IV LEV with IV VPA using common reference-based indirect comparison meta-analysis, and to verify whether results of indirect comparisons are consistent with results of head-to-head randomized controlled trials (RCTs) directly comparing IV LEV with IV VPA.

METHODS

Random-effects Mantel-Haenszel meta-analyses to obtain odds ratios (ORs) for efficacy and safety of LEV versus VPA and LEV or VPA versus PHT were used. Adjusted indirect comparisons between LEV and VPA were used.

RESULTS

Two RCTs comparing LEV with PHT (144 episodes of SE) and 3 RCTs comparing VPA with PHT (227 episodes of SE) were included. Direct comparisons showed no difference in clinical seizure cessation, neither between VPA and PHT (OR: 1.07; 95% CI: 0.57 to 2.03) nor between LEV and PHT (OR: 1.18; 95% CI: 0.50 to 2.79). Indirect comparisons showed no difference between LEV and VPA for clinical seizure cessation (OR: 1.16; 95% CI: 0.45 to 2.97). Results of indirect comparisons are consistent with results of a recent RCT directly comparing LEV with VPA.

CONCLUSION

The absence of a statistically significant difference in direct and indirect comparisons is due to the lack of sufficient statistical power to detect a difference. Conducting a RCT that has not enough people to detect a clinically important difference or to estimate an effect with sufficient precision can be regarded a waste of time and resources and may raise several ethical concerns, especially in RCT on SE.