Phenobarbital Versus Valproate for Generalized Convulsive Status Epilepticus in Adults: A Prospective Randomized Controlled Trial in China

Efficacy of second-line anticonvulsant agents with adult status epilepticus: A systematic review and network meta-analysis

BACKGROUND

Status epilepticus (SE) is potentially life-threatening, however, it is unclear which antiepileptic drugs (AEDs) should be used as second-line AEDs.

OBJECTIVE

We conducted a network meta-analysis (NMA) of randomized controlled trials (RCTs) comparing multiple second-line AEDs for SE to investigate the efficacy of AEDs.

METHODS

We searched MEDLINE, CENTRAL, ClinicalTrials.gov, and World Health Organization International Clinical Trials Platform Search Portal and included RCTs for patients aged ≥15 years with SE on December 31, 2023. We compared multiple second-line AEDs for SE including fosphenytoin (fPHT), lacosamide (LCM), levetiracetam (LEV), phenytoin (PHT), phenobarbital (PHB), and valproate (VPA). The primary and secondly outcomes were termination of seizures integrating the absence of seizure recurrence at 30 min and 60 min, and adverse events associated with AEDs, respectively, with expressing as relative risk (RR) with a 95% confidence interval (CI). We conducted a NMA using frequentist-based approach with multivariate random effects, and assessed the certainty based on the Grading of Recommendations, Assessment, Development, and Evaluations framework.

RESULTS

Seven RCTs (n = 780) were included, and statistically significant difference was detected between VPA vs. PHB (RR, 0.67; 95% CI, 0.53-0.85; very low certainty), fPHT vs. PHB (RR, 0.66; 95% CI, 0.48-0.90; very low certainty), LCM vs. PHB (RR, 0.62; 95% CI, 0.41-0.93; very low certainty), and LEV vs. PHB (RR, 0.69; 95% CI, 0.51-0.94; very low certainty). Moreover, PHB was the highest in the ranking for termination of seizures. For adverse events, no significant reduction was observed owing to the selection of AEDs, although the ranking of PHB was the lowest.

CONCLUSIONS

PHB may have been the most effective for seizure termination as second-line AEDs in adult patients with SE. However, the certainty of almost all comparisons was "very low", and careful interpretation is essential.

Risk factors for super-refractory and mortality in generalized convulsive status epilepticus: a 10-year retrospective cohort study

Background

Generalized convulsive status epilepticus (GCSE) is one of the most challenging life-threatening neurological emergencies. If GCSE becomes super-refractory, it is associated with significant mortality. Although aggressive management of prolonged status epilepticus was conducted, the mortality has not decreased since the late 1990s.

Objectives

The present study aimed to explore the risk factors for progression to super-refractory in patients with generalized convulsive status epilepticus (GCSE). Moreover, we illustrated the risk factors for mortality in GCSE patients.

Design

An observational retrospective cohort study.

Methods

We conducted a retrospective study of patients with GCSE admitted to our neurocritical unit, in Guangzhou, China, from October 2010 to February 2021. The data of sociodemographic information, etiology, laboratory results, treatment, and prognosis were collected and analyzed.

Results

A total of 106 patients were enrolled; 51 (48%) of them developed super-refractory status epilepticus (SRSE). Multivariate logistic regression analysis demonstrated that patients with autoimmune encephalitis (p = 0.015) and intracranial infection (p = 0.019) are likely to progress to SRSE. The in-hospital mortality was 11.8% and 9.1% for patients in the SRSE and non-SRSE groups, respectively (p = 0.652). Multivariate logistic regression analysis showed that neutrophil-to-lymphocyte ratios (NLR) at admission were independently associated with in-hospital mortality. Up to 31.4% of SRSE patients and 29.1% of non-SRSE patients died within 6 months after discharge (p = 0.798). Multivariate logistic regression analysis showed that plasma exchange (PE) was a protective factor for 6-month mortality. A high NLR at discharge was a risk factor for 6-month mortality.

Conclusion

In the current study, about 48% of GCSE patients progressed to SRSE. Regarding etiology, autoimmune encephalitis or intracranial infection was prone to SRSE. No significant differences were observed in the in-hospital and 6-month mortality between SRSE and non-SRSE groups. Multivariate logistic regression analysis showed that NLR at admission and discharge was an independent predictor of in-hospital and 6-month mortality, respectively. Moreover, PE significantly reduced the 6-month mortality.

Long-term follow-up of phenobarbital versus valproate for generalized convulsive status epilepticus in adults: A randomized clinical trial

OBJECTIVE

Intravenous phenobarbital is frequently offered to patients with generalized convulsive status epilepticus (GCSE) in China, but its long-term benefits are unclear. We aimed to evaluate the long-term effects of intravenous phenobarbital on adult patients with GCSE.

METHODS

This randomized clinical trial with a 12-month follow-up was performed in Xuanwu Hospital, Capital Medical University (Beijing, China) between February 2011 and December 2021. After the failure of intravenous diazepam treatment, adult patients with GCSE were randomized to receive either intravenous phenobarbital or valproate. Neurological outcome within 12-month was dichotomized as good (modified Rankin scale, mRS 0-2) or poor (mRS 3-6). Cognitive function was measured by mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA). Hamilton anxiety scale (HAMA) and Hamilton depression scale (HAMD) were tested for mood disorders.

RESULTS

We consecutively recruited 166 patients with GCSE. After excluding individuals with termination after intravenous diazepam (n = 61), and with other exclusion criteria (n = 7), 98 patients were included and 88.0% (66/75) of survivors achieved seizure freedom at 12-month. Forty-five patients (45.92%) had good outcomes at 3-month and 57 patients (58.16%) had good outcomes at 12-month. And 46.67% (35/75) of survivors showed mRS improvement at 12-month (phenobarbital group, n = 17 vs. valproate group, n = 18, P = 0.321). Despite there was no significant difference with respect to good outcomes at 3-month (54.0% vs. 37.5%, P = 0.101), the rate of good outcomes in phenobarbital group was higher than valproate group at 12-month (68.0% vs. 47.92%, P = 0.044). A total of 43 patients successfully participated cognitive and emotional tests. Mild cognitive impairment was found in 7.14% of phenobarbital group and 50.0% in valproate group (P = 0.026). In addition, there were no significant differences with respect to anxiety (36.36% vs. 38.10%) and depression (31.82% vs. 47.62%) between the phenobarbital and valproate groups.

CONCLUSIONS

Combined with long term conventional therapy, intravenous phenobarbital group had more good outcomes than intravenous valproate group in Chinese adult patients with GCSE up to 12-month follow-up. This finding may prompt the option of intravenous phenobarbital especially in patients with limited access to new antiseizure drugs.

Management of convulsive status epilepticus: recent updates

Convulsive status epilepticus (SE) is a medical emergency associated with high morbidity and mortality. Recently, clinical trials and meta-analyses investigating medical treatment of SE have been published. Benzodiazepine is well known as the first-line treatment for SE. Recent evidence suggests the equivalence of intravenous fosphenytoin, valproate, and levetiracetam for treatment of established SE. There is lack of evidence regarding treatment for refractory SE. Intravenous midazolam is commonly used, and recent evidence supports the use of ketamine. Additional studies are needed to improve the management of convulsive SE.

Phenobarbital in Status epilepticus - Rediscovery of an effective drug

Phenobarbital (PB) is one of the oldest Antiseizure Medicines (ASMs), which is in clinical use since 1912. Its value in the treatment of Status epilepticus is currently discussed controversially. Phenobarbital has fallen out of favor in many countries across Europe because of reports of hypotension, arrhythmias, and hypopnea. Phenobarbital has a strong antiseizure effect with remarkably little sedation. It exerts its clinical effects, through the increase of GABE-ergic inhibition and decrease of glutamatergic excitation by inhibition of AMPA receptors. Despite good preclinical evidence, there are remarkably few randomized controlled studies on humans in SE, which suggest, that it is at least as good as lorazepam in first-line treatment in early SE, and significantly better than valproic acid in benzodiazepine-resistant SE. Data from randomized trials and large non-randomized prospective and retrospective studies suggest, that Phenobarbital is well tolerated even if used in very high dose protocols. Thus, despite its decline in its popularity at least in Europe and North America, it should be considered a highly cost-effective treatment for early and established SE, not only in resource-limited settings. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.

[Status epilepticus-Detection and treatment in the intensive care unit]

Status epilepticus is characterized by persistent or repetitive seizures which, without successful treatment, can lead to neuronal damage, neurological deficits and death of the patient.While status epilepticus with motor symptoms can usually be clinically diagnosed, nonconvulsive status epilepticus is often clinically overlooked due to its ambiguous semiology, so that electroencephalography (EEG) recording is necessary. The treatment of status epilepticus is performed in four treatment steps, whereby a difficult to treat status epilepticus is present from the third step at the latest and intensive medical care of the patient is necessary. Timely initiation of treatment and sufficient dosage of anticonvulsive medication are decisive for the success of treatment. There is little evidence for the "late" stages of treatment. Intensive medical measures pose the risk of complications that worsen the prognosis. Especially in nonconvulsive status epilepticus, the use of anesthetics must be weighed against possible complications of mechanical ventilation.

Optimal Management of Status Epilepticus in Children in the Emergency Setting: A Review of Recent Advances

Convulsive status epilepticus (CSE) is the most common neurological emergency in children and the second most common neurological emergency in adults. Mortality is low, but morbidity, including neuro-disability, learning difficulties, and a de-novo epilepsy, may be as high as 22%. The longer the duration of CSE, the more difficult it is to terminate, and the greater the risk of morbidity. Convulsive status epilepticus is usually managed using specific national or local algorithms. The first-line treatment is administered when a tonic-clonic or focal motor clonic seizure has lasted five minutes (impending or premonitory CSE). Second-line treatment is administered when the CSE has persisted after two doses of a first-line treatment (established CSE). Randomised clinical trial (RCT) evidence supports the use of benzodiazepines as a first-line treatment of which the most common are buccal or intra-nasal midazolam, rectal diazepam and intravenous lorazepam. Alternative drugs, for which there are considerably less RCT data, are intra-muscular midazolam and intravenous clonazepam. Up until 2019, phenobarbital and phenytoin (or fosphenytoin) were the preferred second-line treatments but with no good supporting RCT evidence. Robust RCT data are now available which has provided important information on second-line treatments, specifically phenytoin (or fosphenytoin), levetiracetam and sodium valproate. Lacosamide is an alternative second-line treatment but with no supporting RCT evidence. Current evidence indicates that first, buccal or intranasal midazolam or intravenous lorazepam are the most effective and the most patient and carer-friendly first-line anti-seizure medications to treat impending or premonitory CSE and second, that there is no difference in efficacy between levetiracetam, phenytoin (or fosphenytoin) or sodium valproate for the treatment of established CSE. Pragmatically, levetiracetam or sodium valproate are preferred to phenytoin (or fosphenytoin) because of their ease of administration and lack of serious adverse side-effects, including potentially fatal cardiac arrhythmias. Sodium valproate must be used with caution in children aged three and under because of the rare risk of hepatotoxicity and particularly if there is an underlying mitochondrial disorder.

Why won't it stop? The dynamics of benzodiazepine resistance in status epilepticus

Status epilepticus is a life-threatening neurological emergency that affects both adults and children. Approximately 36% of episodes of status epilepticus do not respond to the current preferred first-line treatment, benzodiazepines. The proportion of episodes that are refractory to benzodiazepines is higher in low-income and middle-income countries (LMICs) than in high-income countries (HICs). Evidence suggests that longer episodes of status epilepticus alter brain physiology, thereby contributing to the emergence of benzodiazepine resistance. Such changes include alterations in GABA_A receptor function and in the transmembrane gradient for chloride, both of which erode the ability of benzodiazepines to enhance inhibitory synaptic signalling. Often, current management guidelines for status epilepticus do not account for these duration-related changes in pathophysiology, which might differentially impact individuals in LMICs, where the average time taken to reach medical attention is longer than in HICs. In this Perspective article, we aim to combine clinical insights and the latest evidence from basic science to inspire a new, context-specific approach to efficiently managing status epilepticus.

Clinical Evaluation of Levetiracetam in the Treatment of Epilepsy

Objectives

Epilepsy is a chronic neurological disorder that is characterized by episodes of seizure.

Methods

In this study, patients with status epilepticus in the Intensive Care Unit of the Department of Neurology of Qujing First People's Hospital were collected and treated with levetiracetam injection, continuous bedside EEG monitoring (cEEG) technology, and quantitative EEG (qEEG) technique. The inhibitory effects of different doses of levetiracetam injection and sodium valproate on abnormal discharge, the improvement of clinical symptoms, the incidence of adverse reactions, and prognosis were monitored, analyzed, and compared.

Results

Compared with the experimental group of sodium valproate, 1000 mg/d levetiracetam group and 1500 mg/d levetiracetam group had a high probability of successful symptom control and a short control time. The patients had a low recurrence rate and a long recurrence time, and the probability of abnormal discharge in EEG was low.

Conclusions

The recording results showed that levetiracetam could significantly inhibit the abnormal discharge of patients. Compared with sodium valproate, high-dose levetiracetam is a drug with a rapid effect, good effect, and long action time.

Effectiveness and safety of intravenous valproate in agitation: a systematic review

RATIONALE

The use of intravenous valproate is not approved for clinical practice in psychiatry. Literature data pointed out for a potential usefulness of this route of administration for valproate, but there is no actual consensus.

OBJECTIVES

The aim of the present systematic review is to assess the effectiveness of intravenous valproate in agitation as well as general safety.

METHODS

A systematic review of studies evaluating the use of intravenous valproate in agitation was conducted. Additionally, safety was evaluated in all randomized trials involving the use of intravenous valproate in all medical conditions (epilepsy, migraine and psychiatric conditions).

RESULTS

For the systematic review on effectiveness in agitation, the search yielded 965 articles overall. After removing duplicates, 9411 articles were screened by title and abstract, and 39 of these were evaluated at a full-text level. Six studies were considered eligible for qualitative synthesis: one RCT and case report (n = 3), followed by cohort studies (n = 2). For the systematic review on safety, twenty-two RCTs were considered eligible for quantitative synthesis.

CONCLUSION

Intravenous valproate seems efficacious in reducing agitation in psychiatric patients; it generally appears safe compared to other neuroleptics or antiepileptics. However, the evidence is still not strong as it  relies mainly on open-label studies or case series.

Phenobarbital versus valproate for generalized convulsive status epilepticus in adults (2): A multicenter prospective randomized controlled trial in China (China 2-P vs. V)

OBJECTIVE

A multicenter study of phenobarbital versus valproate (i.e., the China 2-P vs. V study) was conducted to compare the efficacy and safety of phenobarbital and valproate for generalized convulsive status epilepticus (SE) in a multicenter trial design.

METHODS

Three improvements (uniform intravenous pumping, pump speed adjustment according to adverse events and blood drug level monitoring) over a previous study were made regarding an intravenous regimen of phenobarbital and valproate in a multicenter, prospective, randomized, controlled study. Long-term electroencephalography (EEG) monitoring was performed after initial drug treatment. Termination, relapse, adverse event and poor prognosis rates in patients with generalized convulsive status epilepticus (GCSE) were compared.

RESULTS

The rate of GCSE termination within one hour were significantly higher in the phenobarbital group (33 cases) than in the valproate group (36 cases) (84.8 % vs. 63.9 %, P = 0.048), but the rates of nontermination of EEG epileptic discharge within one hour were similar between the two groups (12.1 % vs. 8.3 %, P = 0.702). The relapse and adverse event rates were not significantly different between groups, but 3 hypoventilation events and 1 hypotension event occurred in the phenobarbital group compared to 0 in the valproate group. There were no cases of epileptiform EEG discharge relapse in the phenobarbital group, compared to 1 case in the valproate group.

CONCLUSIONS

The phenobarbital regimen evaluated in this study has a higher GCSE termination rate than the valproate regimen, indicating that the former is suitable for countries, regions and individuals with limited access to new antiepileptic drugs or limited economic means.

Advances in the management of generalized convulsive status epilepticus: what have we learned?

Convulsive status epilepticus is the most serious manifestation of an epileptic diathesis. In the early stages (5-30 min), there exists class A evidence to support the efficacy of benzodiazepines as first-line treatment. As status epilepticus progresses into the later stages, the evidence for treatment becomes less robust until we are depending upon short case series and case reports for the treatment of refractory status epilepticus. However, the past year saw the publication of three randomized controlled trials in the setting of benzodiazepine-resistant established convulsive status epilepticus: the EcLiPSE and ConSEPT studies, compared levetiracetam to phenytoin in children; and the ESETT study compared fosphenytoin, levetiracetam and sodium valproate in adults and children. In addition, the emergence of data from the SENSE study, a multicentre multinational prospective cohort study and the publication of a systematic review and meta-analysis of the mortality of status epilepticus over the past 30 years, has brought the treatment of status epilepticus into sharp focus. In this update we provide a detailed analysis of these studies and their impact on clinical practice. We review contentious areas of management in status epilepticus where a consensus is lacking and advance the case for more research on existing and alternative treatment strategies.

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

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

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.

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.

Intravenous antiepileptic drugs in adults with benzodiazepine-resistant convulsive status epilepticus: A systematic review and network meta-analysis

AIM

The aim of this study was to estimate the comparative efficacy and safety of antiepileptic drugs (AEDs) in adults with benzodiazepine-resistant convulsive status epilepticus (SE).

METHODS

MEDLINE, CENTRAL, ClinicalTrials.gov, and Opengrey.eu were searched (from inception to 3rd April, 2018) for randomized controlled trials (RCTs) of AEDs used intravenously to treat benzodiazepine-resistant SE in adults. Efficacy outcomes were SE cessation within 1 h from drug administration and seizure freedom at 24 h. Safety outcomes were respiratory depression and hypotension. Effect sizes were estimated by network meta-analyses within a frequentist framework. The hierarchy of competing interventions was established using the surface under the cumulative ranking curve (SUCRA) and mean ranks.

RESULTS

Five RCTs were considered, involving 349 patients. Included interventions were valproate (VPA; 20-30 mg/kg), phenytoin (PHT; 20 mg/kg), diazepam (DZP; 0.2 mg/kg, then 4 mg/h), phenobarbital (PHB; 20 mg/kg, then 100 mg every 6 h), lacosamide (LCM; 400 mg), and levetiracetam (LEV; 20 mg/kg); PHB was superior to PHT, VPA, DZP, LEV, and LCM with respect to SE cessation and performed better than VPA, DZP, and LCM in the achievement of seizure freedom at 24 h. No differences were noted between drugs in the occurrence of respiratory depression and hypotension. According to SUCRA, PHB had the greatest probabilities of being best in the achievement of SE control and seizure freedom, whereas VPA and LCM ranked best for the safety outcomes.

CONCLUSIONS

Our study suggests that high-dose PHB is effective in controlling SE and preventing seizure recurrence, and LCM and VPA could be better tolerated options. Further head-to-head comparative studies are strongly required to provide more definitive evidence. This article is part of the Special Issue "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures".

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.

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

Objective

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

Methods

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

Results

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

Conclusion

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

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

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.