Topiramate as an adjunctive treatment in patients with refractory status epilepticus: an observational cohort study

The Bibliometric and Visualized Analysis of Research for Hospital Medication Management Based on the Web of Science Database

Objective

Identify the collaborations between authors, countries, and institutions, respectively, and explore the hot issues and prospects for research on hospital medication management.

Materials and Methods

Publications on hospital medication management were retrieved from the Web of Science Core Collection. Bibliometric analyses were performed using CiteSpace 6.1.R3, HistCite 2.1, and VOSviewer 1.6.16. The network maps were created between authors, countries institutions, and keywords.

Results

A total of 18,723 articles related to hospital medication management studies were identified. Rapid growth in the number of publications since 2017. The high papers were published in AM J HEALTH-SYST PH, while JAMA-J AM MED ASSOC was the most co-cited journal. Manias E and WHO ranked first in the author and cited author. There were active collaborations among the top authors. Bates DW was the key author in this field. The authors have active collaborations in adverse drug events, acute coronary syndrome, in-hospital major bleeding, and so on. The US was the leading contributor in this field. The UK, Australia, and China are also very active. Active cooperation between countries and between institutions was observed. The main hot topics included matters related to outcome indicators, hospital pharmacy service behaviors, and medication use in pain management. More recent keywords focus on chronic disease medication management and clinical medication management.

Conclusion

Hospital medication management studies have significantly increased after 2017. There was active cooperation between authors, countries, and institutions. The application of hospital medication management in the emergency department and the relationship between medication management and medication adherence are current research hotspots. In addition, with the continuous progress of society, chronic diseases have become an important factor affecting people's health, and medication management is becoming more and more subdivided, so the direction of chronic disease medication management as well as precise medication may become the development direction of future research.

The potential of intravenous topiramate for the treatment of status epilepticus

There is considerable clinical evidence that topiramate (TPM) has a high potential in the treatment of refractory and super-refractory status epilepticus (RSE, SRSE). Because TPM is only approved for oral administration, it is applied as suspension via a nasogastric tube for SE treatment. However, this route of administration is impractical in an emergency setting and leads to variable absorption with unpredictable plasma levels and time to peak concentration. Thus, the development of an intravenous (i.v.) solution for TPM is highly desirable. Here we present data on two parenteral formulations of TPM that are currently being developed. One of these solutions is using sulfobutylether-β-cyclodextrin (SBE-β-CD; Captisol®) as an excipient. A 1% solution of TPM in 10% Captisol® has been reported to be well tolerated in safety studies in healthy volunteers and patients with epilepsy or migraine, but efficacy data are not available. The other solution uses the FDA- and EMA-approved excipient amino sugar meglumine. Meglumine is much more effective to dissolve TPM in water than Captisol®. A 1% solution of TPM can be achieved with 0.5-1% of meglumine. While the use of Captisol®-containing solutions is restricted in children and patients with renal impairment, such restrictions do not apply to meglumine. Recently, first-in-human data were reported for a meglumine-based solution of TPM, indicating safety and efficacy when used as a replacement for oral administration in a woman with epilepsy. Based on the multiple mechanisms of action of TPM that directly target the molecular neuronal alterations that are thought to underlie the loss of efficacy of benzodiazepines and other anti-seizure medications during prolonged SE and its rapid brain penetration after i.v. administration, we suggest that parenteral (i.v.) TPM is ideally suited for the treatment of RSE and SRSE. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.

Efficacy of topiramate as an add-on therapy in patients with refractory status epilepticus: a short systematic review

OBJECTIVE

To identify current evidence on the use of topiramate for refractory status epilepticus.

METHODS

We reviewed the literature to investigate the efficacy of topiramate in the treatment of refractory status epilepticus. The search terms used were "status epilepticus", "refractory", "treatment" and "topiramate". No restrictions were used.

RESULTS

The search yielded 487 articles that reported using topiramate as a treatment for refractory status epilepticus and its outcomes. Case reports, review articles, and animal experiments were excluded. After excluding duplicates and applying inclusion and exclusion criteria, nine studies were included for analyses. Descriptive and qualitative analyses were performed, and the results were as follows: response rates (defined as termination in-hospital until 72 hours after the administration of topiramate) varied from 27% to 100%. The mortality rate varied from 5.9% to 68%. Positive functional long-term outcomes, defined as discharge, back to baseline or rehabilitation, were documented by seven studies, and the rates ranged between 4% and 55%. Most studies reported no or mild adverse effects.

CONCLUSION

Topiramate was effective in terminating refractory status epilepticus, presented relatively low mortality and was well tolerated. Therefore, topiramate could be a good option as a third-line therapy for refractory status epilepticus, but further studies are necessary.

Treatment of Super-Refractory Status Epilepticus: A Review

PURPOSE

Super-refractory status epilepticus (SRSE) presents management challenges due to the absence of randomized controlled trials and a plethora of potential medical therapies. The literature on treatment options for SRSE reports variable success and quality of evidence. This review is a sequel to the 2020 American Epilepsy Society (AES) comprehensive review of the treatment of convulsive refractory status epilepticus (RSE).

METHODS

We sought to determine the effectiveness of treatment options for SRSE. We performed a structured literature search (MEDLINE, Embase, CENTRAL, CINAHL) for studies on reported treatments of SRSE. We excluded antiseizure medications (ASMs) covered in the 2016 AES guideline on the treatment of established SE and the convulsive RSE comprehensive review of the 2020 AES. Literature was reviewed on the effectiveness of vagus nerve stimulation, ketogenic diet (KD), lidocaine, inhalation anesthetics, brain surgery, therapeutic hypothermia, perampanel, pregabalin (PGB), and topiramate in the treatment of SRSE. Two authors reviewed each therapeutic intervention. We graded the level of the evidence according to the 2017 classification scheme of the American Academy of Neurology.

RESULTS

For SRSE (level U; 39 class IV studies total), insufficient evidence exists to support that perampanel, PGB, lidocaine, or acute vagus nerve stimulation (VNS) is effective. For children and adults with SRSE, insufficient evidence exists to support that the KD is effective (level U; 5 class IV studies). For adults with SRSE, insufficient evidence exists that brain surgery is effective (level U, 7 class IV studies). For adults with SRSE insufficient, evidence exists that therapeutic hypothermia is effective (level C, 1 class II and 4 class IV studies). For neonates with hypoxic-ischemic encephalopathy, insufficient evidence exists that therapeutic hypothermia reduces seizure burden (level U; 1 class IV study). For adults with SRSE, insufficient evidence exists that inhalation anesthetics are effective (level U, 1 class IV study) and that there is a potential risk of neurotoxicity.

CONCLUSION

For patients with SRSE insufficient, evidence exists that any of the ASMs reviewed, inhalational anesthetics, ketogenic diet, acute VNS, brain surgery, and therapeutic hypothermia are effective treatments. Data supporting the use of these treatments for SRSE are scarce and limited mainly to small case series and case reports and are confounded by differences in patients' population, and comedications, among other factors.

Therapeutic Options for Patients with Refractory Status Epilepticus in Palliative Settings or with a Limitation of Life-Sustaining Therapies: A Systematic Review

BACKGROUND

Refractory status epilepticus (RSE) represents a serious medical condition requiring early and targeted therapy. Given the increasing number of elderly or multimorbid patients with a limitation of life-sustaining therapy (LOT) or within a palliative care setting (PCS), guidelines-oriented therapy escalation options for RSE have to be omitted frequently.

OBJECTIVES

This systematic review sought to summarize the evidence for fourth-line antiseizure drugs (ASDs) and other minimally or non-invasive therapeutic options beyond guideline recommendations in patients with RSE to elaborate on possible treatment options for patients undergoing LOT or in a PCS.

METHODS

A systematic review of the literature in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, focusing on fourth-line ASDs or other minimally or non-invasive therapeutic options was performed in February and June 2020 using the MEDLINE, EMBASE and Cochrane databases. The search terminology was constructed using the name of the specific ASD or therapy option and the term 'status epilepticus' with the use of Boolean operators, e.g. "(brivaracetam) AND (status epilepticus)". The respective Medical Subject Headings (MeSH) and Emtree terms were used, if available.

RESULTS

There is currently no level 1, grade A evidence for the use of ASDs in RSE. The best evidence was found for the use of lacosamide and topiramate (level 3, grade C), followed by brivaracetam, perampanel (each level 4, grade D) and stiripentol, oxcarbazepine and zonisamide (each level 5, grade D). Regarding non-medicinal options, there is little evidence for the use of the ketogenic diet (level 4, grade D) and magnesium sulfate (level 5, grade D) in RSE. The broad use of immunomodulatory or immunosuppressive treatment options in the absence of a presumed autoimmune etiology cannot be recommended; however, if an autoimmune etiology is assumed, steroid pulse, intravenous immunoglobulins and plasma exchange/plasmapheresis should be considered (level 4, grade D). Even if several studies suggested that the use of neurosteroids (level 5, grade D) is beneficial in RSE, the current data situation indicates that there is formal evidence against it.

CONCLUSIONS

RSE in patients undergoing LOT or in a PCS represents a challenge for modern clinicians and epileptologists. The evidence for the use of ASDs in RSE beyond that in current guidelines is low, but several effective and well-tolerated options are available that should be considered in this patient population. More so than in any other population, advance care planning, advance directives, and medical ethical aspects have to be considered carefully before and during therapy.

Treatment of status epilepticus with zonisamide: A multicenter cohort study of 34 patients and review of literature

INTRODUCTION

We present a summary of clinical cases of oral zonisamide (ZNS) used to treat refractory and super-refractory episodes of status epilepticus (SE).

METHODS

Zonisamide administration in SE was identified in the clinical records of patients treated in Frankfurt and Marburg between 2011 and 2017.

RESULTS

Zonisamide was administered during a total of 37 SE episodes in 34 patients with a mean age of 58.7 ± 17.8 years, 21 of them were female (61.7%). The median latency from the onset of SE to administration of ZNS was 6.3 days. Patients had already undergone unsuccessful treatment with a median of three other antiseizure drugs (ASDs). The median initial dose of ZNS was 100 mg/d, titrated to a median maintenance dose of 400 mg/d. Patients underwent ZNS treatment for a median period of 7 days. Zonisamide was the final drug administered in 9 of 37 (24.3%) episodes, with a clinical effect attributed to ZNS observed in 6 of 37 (16.2%) episodes. An effect attributed to ZNS was observed in 5 out of 30 episodes of refractory SE (RSE) and in one out of 7 episodes of super-refractory SE (SRSE). Possible negative side effects of ZNS were observed in two patients (one patient each with ataxia and skin rash). The mortality rate in hospitalized patients was 10.4% (n = 4).

CONCLUSION

The rate of SE resolution attributed to ZNS treatment (16.2%) can be considered relevant, particularly since ZNS treatment tends to be administered only after several other options have been tried, and has a treatment latency of over six days. Zonisamide may therefore be considered as an alternative oral treatment option in RSE and SRSE.

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

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

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.

Novel drugs and early polypharmacotherapy in status epilepticus

PURPOSE

Rescue medications for status epilepticus (SE) have a relatively high rate of failure. The purpose of this review is to summarize the evidence for the efficacy of novel drugs and early polypharmacotherapy for SE.

METHOD

Literature review.

RESULTS

New drugs and treatment strategies aim to target the pathophysiology of SE in order to improve seizure control and outcomes. Changes at the synapse level during SE include a progressive decrease in synaptic GABA_A receptors and increase in synaptic NMDA receptors. These changes tend to promote self-sustaining seizures. Current SE guidelines recommend a rapid stepwise treatment using benzodiazepines in monotherapy as the first-line treatment, targeting GABA_A synaptic receptors. Novel treatment approaches target GABA_A synaptic and extrasynaptic receptors with allopregnanolone, and NMDA receptors with ketamine. Novel rescue treatments used for SE include topiramate, brivaracetam, and perampanel, which are already marketed in epilepsy. Some available drugs not marketed for use in epilepsy have been used in the treatment of SE, and other agents are being studied for this purpose. Early polytherapy, most frequently combining a benzodiazepine with a second-line drug or an NMDA receptor antagonist, might potentially increase seizure control with relatively minor increase in side effects. Although many preclinical studies support novel drugs and early polytherapy in SE, human studies are scarce and inconclusive. Currently, evidence is lacking to recommend specific combinations of these new agents.

CONCLUSIONS

Novel drugs and strategies target the underlying pathophysiology of SE with the intent to improve seizure control and outcomes.

Treatment of Refractory and Super-refractory Status Epilepticus

Refractory and super-refractory status epilepticus (SE) are serious illnesses with a high risk of morbidity and even fatality. In the setting of refractory generalized convulsive SE (GCSE), there is ample justification to use continuous infusions of highly sedating medications-usually midazolam, pentobarbital, or propofol. Each of these medications has advantages and disadvantages, and the particulars of their use remain controversial. Continuous EEG monitoring is crucial in guiding the management of these critically ill patients: in diagnosis, in detecting relapse, and in adjusting medications. Forms of SE other than GCSE (and its continuation in a "subtle" or nonconvulsive form) should usually be treated far less aggressively, often with nonsedating anti-seizure drugs (ASDs). Management of "non-classic" NCSE in ICUs is very complicated and controversial, and some cases may require aggressive treatment. One of the largest problems in refractory SE (RSE) treatment is withdrawing coma-inducing drugs, as the prolonged ICU courses they prompt often lead to additional complications. In drug withdrawal after control of convulsive SE, nonsedating ASDs can assist; medical management is crucial; and some brief seizures may have to be tolerated. For the most refractory of cases, immunotherapy, ketamine, ketogenic diet, and focal surgery are among several newer or less standard treatments that can be considered. The morbidity and mortality of RSE is substantial, but many patients survive and even return to normal function, so RSE should be treated promptly and as aggressively as the individual patient and type of SE indicate.

Updates in Refractory Status Epilepticus

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

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.

Status Epilepticus in Adults: A Review of Diagnosis and Treatment

Status epilepticus is a medical emergency that requires rapid diagnosis and treatment. Nonconvulsive status epilepticus is frequently underdiagnosed and therefore undertreated, which can lead to permanent neuronal damage resulting in disability or death. Despite the frequent occurrence and morbidity associated with status epilepticus, this topic has received little attention within the literature. A systematic approach to treatment should start with management of airway, breathing, and circulation, followed by administration of benzodiazepines and intravenous antiepileptic drugs, and rapid escalation of therapy to prevent morbidity and mortality. Armed with the information in this article, nurses will have a higher-level understanding of what to do when encountering a patient in status epilepticus.

Topiramate in the Treatment of Generalized Convulsive Status Epilepticus in Adults: A Systematic Review with Individual Patient Data Analysis

BACKGROUND

Generalized convulsive status epilepticus (GCSE) is a medical emergency associated with high morbidity and mortality that requires prompt medical intervention. Topiramate (TPM) is an antiepileptic drug effective against a broad spectrum of seizure types, and has been proposed as a possible therapeutic option for super-refractory status epilepticus (SRSE), the most severe form of GCSE.

AIM

This review aimed to evaluate the role of TPM in GCSE, including SRSE.

METHODS

MEDLINE, CENTRAL, ClinicalTrials.gov, LILACS, Google Scholar, and Opengrey.eu were systematically searched. We compared: (1) patients who did and who did not receive TPM as their last drug; (2) patients receiving TPM as the last drug and achieving SE control and patients receiving TPM as the last drug but without termination of SE.

RESULTS

The literature search yielded 1164 results, with individual data available for 35 patients (six with SRSE) from four studies. SE was controlled in 68.6% of patients receiving TPM either as the last drug (20) or not (15), and in 14 of the 20 patients receiving TPM as the last drug (70%). Only six patients received TPM for SRSE; in five of them, TPM was administered as the last drug with resolution of SE in four. When comparing patients who did and did not receive TPM as the last drug, no statistically significant difference was found for any of the variables considered; similarly, no difference was found comparing patients receiving TPM as the last drug and achieving SE control with those receiving TPM as the last drug but without termination of SE.

CONCLUSIONS

The lack of a statistically significant difference is likely to be due to the small sample size. In only a few patients was TPM used for SRSE. There is an unmet need for high-quality studies to evaluate the role of TPM in GCSE.

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

Nonconvulsive status epilepticus in adults - insights into the invisible

Nonconvulsive status epilepticus (NCSE) is a state of continuous or repetitive seizures without convulsions. Owing to the nonspecific symptoms and considerable morbidity and mortality associated with NCSE, clinical research has focused on early diagnosis, risk stratification and seizure termination. The subtle symptoms and the necessity for electroencephalographic confirmation of seizures result in under-diagnosis with deleterious consequences. The introduction of continuous EEG to clinical practice, and the characterization of electrographic criteria have delineated a number of NCSE types that are associated with different prognoses in several clinical settings. Epidemiological studies have uncovered risk factors for NCSE; knowledge of these factors, together with particular clinical characteristics and EEG observations, enables tailored treatment. Despite these advances, NCSE can be refractory to antiepileptic drugs, necessitating further escalation of treatment. The presumptive escalation to anaesthetics, however, has recently been questioned owing to an association with increased mortality. This Review compiles epidemiological, clinical and diagnostic aspects of NCSE, and considers current treatment options and prognosis.

Assessing the value of topiramate in refractory status epilepticus

PURPOSE

The aim of this study was to assess factors associated with the use of topiramate (TPM) in refractory status epilepticus (RSE).

METHODS

We retrospectively reviewed RSE episodes over a 12-year period. Episodes treated with and without TPM were compared in terms of demographics, RSE characteristics, clinical course, and outcome in univariate and multivariate analyses. Subgroups defined by type of RSE were studied separately. Functional outcome was assessed with the modified Rankin Scale.

RESULTS

Among 71 episodes, 17 (23.9%) were treated with TPM and seizure control was achieved in all of these. The results of unadjusted comparisons suggested a use of TPM in younger and healthier patients who received more perseverant treatment indicated by a higher number of antiepileptic drugs applied. In multivariate analysis adjusting for RSE duration, however, these associations lost significance. Furthermore, TPM was not a predictor of successful RSE termination in neither the overall cohort, nor in the subgroup of complex-partial RSE.

CONCLUSION

After multivariate adjustment, no significant differences were observed between episodes treated with and without TPM in baseline characteristics, treatment, and outcome. Regarding the latter, this study does therefore not yield evidence for a particular efficacy of TPM in RSE.

Treatment of Convulsive Status Epilepticus

OPINION STATEMENT

Convulsive status epilepticus (CSE) is a medical emergency with an associated high mortality and morbidity. It is defined as a convulsive seizure lasting more than 5 min or consecutive seizures without recovery of consciousness. Successful management of CSE depends on rapid administration of adequate doses of anti-epileptic drugs (AEDs). The exact choice of AED is less important than rapid treatment and early consideration of reversible etiologies. Current guidelines recommend the use of benzodiazepines (BNZ) as first-line treatment in CSE. Midazolam is effective and safe in the pre-hospital or home setting when administered intramuscularly (best evidence), buccally, or nasally (the latter two possibly faster acting than intramuscular (IM) but with lower levels of evidence). Regular use of home rescue medications such as nasal/buccal midazolam by patients and caregivers for prolonged seizures and seizure clusters may prevent SE, prevent emergency room visits, improve quality of life, and lower health care costs. Traditionally, phenytoin is the preferred second-line agent in treating CSE, but it is limited by hypotension, potential arrhythmias, allergies, drug interactions, and problems from extravasation. Intravenous valproate is an effective and safe alternative to phenytoin. Valproate is loaded intravenously rapidly and more safely than phenytoin, has broad-spectrum efficacy, and fewer acute side effects. Levetiracetam and lacosamide are well tolerated intravenous (IV) AEDs with fewer interactions, allergies, and contraindications, making them potentially attractive as second- or third-line agents in treating CSE. However, data are limited on their efficacy in CSE. Ketamine is probably effective in treating refractory CSE (RCSE), and may warrant earlier use; this requires further study. CSE should be treated aggressively and quickly, with confirmation of treatment success with epileptiform electroencephalographic (EEG), as a transition to non-convulsive status epilepticus is common. If the patient is not fully awake, EEG should be continued for at least 24 h. How aggressively to treat refractory non-convulsive SE (NCSE) or intermittent non-convulsive seizures is less clear and requires additional study. Refractory SE (RSE) usually requires anesthetic doses of anti-seizure medications. If an auto-immune or paraneoplastic etiology is suspected or no etiology can be identified (as with cryptogenic new onset refractory status epilepticus, known as NORSE), early treatment with immuno-modulatory agents is now recommended by many experts.

Are Newer AEDs Better Than the Classic Ones in the Treatment of Status Epilepticus?

Several newer antiepileptic drugs have been increasingly used in patients with status epilepticus, especially levetiracetam and lacosamide, because of their intravenous availability. They may offer advantages in terms of tolerability; however, to date, no clear evidence suggests any advantage regarding efficacy after the use of newer antiepileptic drugs in this specific clinical setting. However, there has been a considerable revival of interest regarding some classic compounds, such as midazolam (MDZ), valproate (VPA), ketamine, or ketogenic diet. Awaiting comparative studies, which in part are ongoing, it seems reasonable, for the first choice, to rely on those agents that are best known and less expensive.

Pharmacotherapy for Status Epilepticus

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

Comparison of the effectiveness of four antiepileptic drugs in the treatment of status epilepticus according to four different efficacy criteria

The preliminary data presented here shall give an impression on how different criteria for the identification of an antiepileptic drug (AED) with a possible or certain treatment effect can have an influence on the results of retrospective case series. We present a data subset from a large retrospective study which, when completed, will cover all treatment episodes of status epilepticus (SE) at the neurological department of the Universitätsmedizin Rostock from January 2010 to June 2013. We compare and contrast the results of four different efficacy criteria for the effectiveness of phenytoin (PHT), valproate (VPA), levetiracetam (LEV), and lacosamide (LCM): criterion 1 = the last AED administered before SE termination; criterion 2 = the last drug introduced into the antiepileptic therapy within 72 h before SE termination and without changes in the comedication; criterion 3 = the last drug introduced into the antiepileptic therapy or increased in dose within 24h before SE termination without changes in the comedication; and criterion 4 = the last drug introduced into the antiepileptic therapy within 72 h before SE termination, even allowing changes in the comedication. Thirty-seven treatment episodes in 32 patients (13 male and 19 female, mean age at first episode: 68 years, SD: 17) could be analyzed. In 31 episodes, at least one AED was given intravenously. Efficacy rates in the whole case series according to all four criteria were not significantly different between the four AEDs, but there was a considerable difference in the efficacy rates of each AED when evaluating them with the different efficacy criteria. Our data show that statistically significant results concerning the efficacy of different AEDs in different subtypes of SE may depend on the outcome criteria. Therefore, efficacy criteria for the effectiveness of AEDs in the treatment of SE should be standardized. This article is part of a Special Issue entitled Status Epilepticus.

Efficacy of perampanel in refractory nonconvulsive status epilepticus and simple partial status epilepticus

We provide some evidence concerning the efficacy of perampanel (PER) in refractory status epilepticus (SE). We retroactively identified patients with SE treated in our department by searching for the term "status epilepticus" in the electronic archive of medical records. We present and analyze in this paper the subset of data of the patients treated with PER. We analyzed ten episodes of SE in nine patients. At the first administration, PER was given in a dosage of 6mg to most of our patients (7 of 10). On average, PER was administered as the 6th antiepileptic drug (AED) (range: 2-10). Depending on the criterion for efficacy, PER appears effective for the termination of SE in 2 to 6 (of 10) episodes. Unfortunately, safety data for the administration of PER with loading doses needed for the treatment of SE are lacking. Because of this, PER should be used very carefully in refractory SE and only after first-line treatment options have failed.

Enteral topiramate in a pediatric patient with refractory status epilepticus: a case report and review of the literature

We describe the use of topiramate in a healthy 12-year-old (88-kg) male who developed refractory generalized convulsive status epilepticus. Seizures persisted despite aggressive use of benzodiazepines (intravenous lorazepam; oral clorazepate), barbiturates (i.e., phenobarbital, pentobarbital), and hydantoins. The child's seizures were controlled with nasogastrically administered topiramate in doses up to 500 mg twice daily (11.4 mg/kg/day). The patient did not display any clinical or laboratory signs of metabolic acidosis while receiving topiramate. Topiramate should be considered as a treatment option in refractory status epilepticus.

Induction of burst suppression or coma using intravenous anesthetics in refractory status epilepticus

General anesthetic-induced coma therapy has been recommended for the treatment of refractory status epilepticus (RSE). However, the influence of electroencephalographic (EEG) burst suppression (BS) on outcomes still remains unclear. This study investigated the impact of intravenous anesthetic-induced BS on the prognosis of RSE using a retrospective analysis of all consecutive adult patients who received intravenous anesthetic treatment for RSE at the Seoul National University Hospital between January 2006 and June 2011. Twenty-two of the 111 episodes of RSE were enrolled in this study. Of the 22 RSE patients, 12 (54.5%) were women and 18 (81.4%) exhibited generalized convulsive status epilepticus. Sixteen patients (72.7%) were classified as having acute symptomatic etiology, including three patients with anoxic encephalopathy, and others with remote symptomatic etiology. Only two patients (9.1%) had a favorable Status Epilepticus Severity Score (0-2) at admission. All patients received midazolam (MDZ) as a primary intravenous anesthetic drug for RSE treatment; three (13.6%) received MDZ and propofol, and one (4.5%) received MDZ and pentobarbital. The rates of mortality and poor outcome at discharge were 13.6% (n=3) and 54.5% (n=12), respectively. While BS was achieved in six (27.5%) patients, it was not associated with mortality or poor outcome. Induced BS was associated with prolonged hospital stay in subgroup analysis when excluding anoxic encephalopathy. Our results suggest that induction of BS for treating RSE did not affect mortality or outcome at discharge and may lead to an increased length of hospital stay.

Treatment of refractory generalized convulsive status epilepticus with enteral topiramate in resource limited settings

PURPOSE

To explore the feasibility, safety and efficacy of enterally administered topiramate (TPM) as an adjunctive treatment for adult patients with refractory generalized convulsive status epilepticus (RGCSE).

METHODS

This prospective open-label non-randomized clinical trial was performed at Namazee hospital, Shiraz University of Medical Sciences, Shiraz, Iran from January 2013 through February 2014. Patients 18 years of age and older with RGCSE were enrolled. Topiramate was used, in case of failure of at least two standard anti-epileptic drugs in patients in whom the standard third or fourth line therapies were not available. Topiramate tablets were crushed and administered through the nasogastric tube; 400mg stat and then 200mg Bid. Status epilepticus response to TPM was categorized as successful (termination of SE within 24h following TPM introduction, without modification of concomitant AEDs), possible (SE termination associated with the introduction of TPM, concomitantly with other medications) or unsuccessful.

RESULTS

Twenty patients were studied. Topiramate was successful in terminating SE in five (25%) patients; possibly successful in 11 (55%); and not successful in four (20%). No clinically significant adverse effects related to TPM administration were observed. Eleven (55%) patients returned to their baseline clinical condition at the time of discharge from the hospital, but two (10%) patients did not.

CONCLUSION

Treatment with enterally administered topiramate could potentially be efficacious in some patients and appeared to be tolerated well in patients with RGCSE. Low cost and feasibility makes TPM a potentially useful agent in treating patients with RGCSE, especially in resource limited settings.

Indomethacin can downregulate the levels of inflammatory mediators in the hippocampus of rats submitted to pilocarpine-induced status epilepticus

OBJECTIVE

Refractory status epilepticus is one of the most life-threatening neurological emergencies and is characterized by high morbidity and mortality. Additionally, the use of anti-inflammatory drugs during this period is very controversial. Thus, this study has been designed to analyze the effect of a low dose of indomethacin (a COX inhibitor) on the expression of inflammatory molecules.

METHOD

The hippocampus of rats submitted to pilocarpine-induced long-lasting status epilepticus was analyzed to determine the expression of inflammatory molecules with RT-PCR and immunohistochemistry.

RESULTS

Compared with controls, reduced levels of the kinin B2 receptors IL1β and TNFα were found in the hippocampus of rats submitted to long-lasting status epilepticus and treated with indomethacin.

CONCLUSIONS

These data show that low doses of indomethacin could be employed to minimize inflammation during long-lasting status epilepticus.

Factors influencing response to intravenous lacosamide in emergency situations: LACO-IV study

Status epilepticus (SE) and acute repetitive seizures (ARSs) frequently result in emergency visits. Wide variations in response are seen with standard antiepileptic drugs (AEDs). Oral and intravenous (IV) formulations of lacosamide are approved as adjunctive therapy in the treatment of partial-onset seizures in adults and adolescents. The aim of the retrospective multicenter observational study (LACO-IV) was to analyze data from a large cohort of patients with SE or ARSs of varying severity and etiology, who received IV lacosamide in the emergency setting. Patient clinical data were entered into a database; lacosamide use and efficacy and tolerability variables were analyzed. In SE, IV lacosamide tended to be used mainly in nonconvulsive status epilepticus as second- or third-line treatment. The proportion of patients with no seizures when IV lacosamide was the last drug administered was 76.5% (70.9% SE and 83.7% ARSs). The rate of seizure cessation ≤ 24 h after IV lacosamide administration was 57.1% (49.1% SE and 67.4% ARSs). Of the factors analyzed, a shorter latency from seizure onset to IV lacosamide infusion influenced treatment response significantly. A nonsignificant tendency towards a higher response was seen with lacosamide dose >200mg versus ≤ 200 mg. Analysis of response according to mechanism of action showed no significant differences in response to IV lacosamide in patients receiving prior sodium channel blocker (SCB) or non-SCB AEDs in the overall or SE population; however, in ARSs, a tendency towards a higher response was observed in those receiving non-SCB AEDs. The frequency and nature of adverse events observed were in line with those reported in other studies (somnolence being the most frequent). In the absence of randomized prospective controlled studies of IV lacosamide, our observations suggest that IV lacosamide may be a potential alternative for treatment of SE/ARSs when seizures fail to improve with standard AEDs or when AEDs are contraindicated or not recommended.

Status epilepticus: an update

Status epilepticus (SE) still results in significant mortality and morbidity. Whereas mortality depends mainly on the age of the patient as well as the cause, morbidity is often due to the myriad of complications that occur during prolonged admission to an intensive care environment. Although SE is a clinical diagnosis in most cases (convulsant), its treatment requires support by continuous electroencephalographic recording to ensure cessation of potential nonconvulsive elements of SE. Treatment has recently changed to incorporate four stages and must be initiated at the earliest possible time.

Anesthetic drugs in status epilepticus: risk or rescue? A 6-year cohort study

OBJECTIVE

To evaluate the risks of continuously administered IV anesthetic drugs (IVADs) on the outcome of adult patients with status epilepticus (SE).

METHODS

All intensive care unit patients with SE from 2005 to 2011 at a tertiary academic medical care center were included. Relative risks were calculated for the primary outcome measures of seizure control, Glasgow Outcome Scale score at discharge, and death. Poisson regression models were used to control for possible confounders and to assess effect modification.

RESULTS

Of 171 patients, 37% were treated with IVADs. Mortality was 18%. Patients with anesthetic drugs had more infections during SE (43% vs 11%; p < 0.0001) and a 2.9-fold relative risk for death (2.88; 95% confidence interval 1.45-5.73), independent of possible confounders (i.e., duration and severity of SE, nonanesthetic third-line antiepileptic drugs, and critical medical conditions) and without significant effect modification by different grades of SE severity and etiologies. As IVADs were used after first- and second-line drugs failed, there was a correlation between treatment-refractory SE and the use of IVADs, leading to insignificant results regarding the risk of IVADs and outcome after additional adjustment for refractory SE.

CONCLUSION

Our findings heighten awareness regarding adverse effects of IVADs. Randomized controlled trials are needed to further clarify the association of IVADs with outcome in patients with SE.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that patients with SE receiving IVADs have a higher proportion of infection and an increased risk of death as compared to patients not receiving IVADs.

The efficacy of intravenous sodium valproate and phenytoin as the first-line treatment in status epilepticus: a comparison study

Background

Status epilepticus (SE) is a serious neurological condition and requires prompt treatment. Sodium valproate has been used to treat SE successfully but its role as the first-line antiepileptic drug (AED) is still controversial. This study evaluated the efficacy of intravenous sodium valproate to determine if it is non-inferior to intravenous phenytoin in SE treatment.

Methods

Patients diagnosed as SE during 2003–2010 who were of an age of more than 15 years and received either intravenous sodium valproate or intravenous phenytoin as the first-line treatment were enrolled. Clinical characteristics and outcomes of SE were recorded and analyzed. The differences of outcomes between sodium valproate and phenytoin group were determined by descriptive statistics.

Results

During the study period, there were 37 and 17 SE patients who received intravenous phenytoin and intravenous sodium valproate as the first-line treatment, respectively. All patients received diazepam 10 mg intravenously as a rescue medication before starting the antiepileptic agents if uncontrolled except one patient in the sodium valproate group. There were no significant differences between the phenytoin and sodium valproate groups in all outcome variables including numbers of patients with clinically-controlled seizures, non-dependent patients, time to seizure control, and duration of hospitalization, and death. No serious cardiovasculars event such as hypotension occurred in either group.

Conclusion

Intravenous sodium valproate is non-inferior to intravenous phenytoin as the first-line treatment in SE with no significant cardiovascular compromises.

Adverse drug reactions induced by valproic acid

Valproic acid is a widely-used first-generation antiepileptic drug, prescribed predominantly in epilepsy and psychiatric disorders. VPA has good efficacy and pharmacoeconomic profiles, as well as a relatively favorable safety profile. However, adverse drug reactions have been reported in relation with valproic acid use, either as monotherapy or polytherapy with other antiepileptic drugs or antipsychotic drugs. This systematic review discusses valproic acid adverse drug reactions, in terms of hepatotoxicity, mitochondrial toxicity, hyperammonemic encephalopathy, hypersensitivity syndrome reactions, neurological toxicity, metabolic and endocrine adverse events, and teratogenicity.

Treatment of status epilepticus with ketamine, are we there yet?

Status epilepticus (SE), a neurological emergency both in adults and in children, could lead to brain damage and even death if untreated. Generalized convulsive SE (GCSE) is the most common and severe form, an example of which is that induced by organophosphorus nerve agents. First- and second-line pharmacotherapies are relatively consensual, but if seizures are still not controlled, there is currently no definitive data to guide the optimal choice of therapy. The medical community seems largely reluctant to use ketamine, a noncompetitive antagonist of the N-methyl-d-aspartate glutamate receptor. However, a review of the literature clearly shows that ketamine possesses, in preclinical studies, antiepileptic properties and provides neuroprotection. Clinical evidences are scarcer and more difficult to analyze, owing to a use in situations of polytherapy. In absence of existing or planned randomized clinical trials, the medical community should make up its mind from well-conducted preclinical studies performed on appropriate models. Although potentially active, ketamine has no real place for the treatment of isolated seizures, better accepted drugs being used. Its best usage should be during GCSE, but not waiting for SE to become totally refractory. Concerns about possible developmental neurotoxicity might limit its pediatric use for refractory SE.

Seizures and the neurosurgical intensive care unit

The cause of seizures in the neurosurgical intensive care unit (NICU) can be categorized as emanating from either a primary brain pathology or from physiologic derangements of critical care illness. Patients are typically treated with parenteral antiepileptic drugs. For early onset ICU seizures that are easily controlled, data support limited treatment. Late seizures have a more ominous risk for subsequent epilepsy and should be treated for extended periods of time or indefinitely. This review ends by examining the treatment algorithms for simple seizures and status epilepticus and the role newer antiepileptic use can play in the NICU.