Status epilepticus and refractory status epilepticus management

Treatment of pediatric convulsive status epilepticus

Status epilepticus is one of the most common life-threatening neurological emergencies in childhood with the highest incidence in the first 5 years of life and high mortality and morbidity rates. Although it is known that a delayed treatment and a prolonged seizure can cause permanent brain damage, there is evidence that current treatments may be delayed and the medication doses administered are insufficient. Here, we summarize current knowledge on treatment of convulsive status epilepticus in childhood and propose a treatment algorithm. We performed a structured literature search via PubMed and ClinicalTrails.org and identified 35 prospective and retrospective studies on children <18 years comparing two and more treatment options for status epilepticus. The studies were divided into the commonly used treatment phases. As a first-line treatment, benzodiazepines buccal/rectal/intramuscular/intravenous are recommended. For status epilepticus treated with benzodiazepine refractory, no superiority of fosphenytoin, levetirazetam, or phenobarbital was identified. There is limited data on third-line treatments for refractory status epilepticus lasting >30 min. Our proposed treatment algorithm, especially for children with SE, is for in and out-of-hospital onset aids to promote the establishment and distribution of guidelines to address the treatment delay aggressively and to reduce putative permanent neuronal damage. Further studies are needed to evaluate if these algorithms decrease long-term damage and how to treat refractory status epilepticus lasting >30 min.

Efficacy and safety of levetiracetam versus valproate in patients with established status epilepticus: A systematic review and meta-analysis

Objective

Status epilepticus (SE) is a common neurological emergency that is defined as a prolonged seizure or a series of seizures which often leads to irreversible damage. Levetiracetam (LEV) and valproate (VPA) are second-line anti-seizure drugs that are frequently used in patients with established SE (ESE). This meta-analysis compared the efficacy and safety of LEV and VPA for the treatment of ESE.

Method

MEDLINE, EMBASE, Central Register of Controlled Trials (CENTRAL), and clinicaltrials.gov were searched by two authors, which identified six randomized controlled trials (RCTs) that compared LEV and VPA for ESE.

Results

The six RCTs included 1213 patients (LEV group, n = 593; VPA group, n = 620). Integrated patient data information display LEV was not superior to VPA in terms of clinical seizure termination (63.55% vs. 64.08%, respectively; relative risk [RR] = 1.03, 95% confidence interval [CI] = 0.94-1.11, p = 0.55), with no significant differences between LEV and VPA in terms of good functional outcome at discharge (Glasgow Outcome Scale [GOS] = 4 or 5), intensive care unit (ICU) admission, adverse events, and mortality. There was no statistically significant difference between the two drugs in different age groups. Previous multicenter studies have demonstrated that VPA was slightly more effective than LEV, whereas single-center studies showed the opposite results. In addition, LEV and VPA had similar rates of clinical seizure termination, ICU admission, and adverse events between the age subgroups (ages <18 and >18 years).

Conclusions

Levetiracetam (LEV) was not superior to valproate (VPA) in terms of efficacy or safety outcomes. In addition, children (<18 years) and adults (>18 years) might have similar responses to LEV and VPA. Additional RCTs are required to verify our results.

Pharmacokinetic Modeling of Optimized Midazolam and Pentobarbital Dosing Used in Treatment Protocols of Refractory Status Epilepticus

OBJECTIVES

To model bolus dosing, infusion rate, and weaning rate on theoretical serum concentration of midazolam and pentobarbital used in the treatment of refractory status epilepticus (RSE).

DESIGN

One- and two-compartment in silico pharmacokinetic models of midazolam and pentobarbital.

SETTING

Not applicable.

SUBJECTS

Not applicable.

INTERVENTIONS

We compared the model variables used in midazolam and pentobarbital protocols for standard RSE.

MEASUREMENTS AND MAIN RESULTS

Standard RSE treatment protocols result in steady-state serum concentrations that are 6.2-9.0-fold higher for the one-compartment model and 2.3-4.7-fold higher for the two-compartment model. In the model, not including bolus doses delays the achievement of serum steady-state concentration by 0.5 and 2.7 hours for midazolam and pentobarbital, respectively. Abrupt discontinuation of these medications reduces modeled medication exposure by 1.1 and 6.4 hours, respectively.

CONCLUSIONS

Our in silico pharmacokinetic modeling of standard midazolam and pentobarbital dosing protocols for RSE suggests potential variables to optimize in future clinical studies.

Electroconvulsive therapy use for refractory status epilepticus in an implantable vagus nerve stimulation patient: A case report

INTRODUCTION

Status epilepticus (SE) has a mortality rate of 20 to 50%, with acute symptomatic SE having a higher risk compared to chronic SE. Electroconvulsive therapy (ECT) has been utilized for the treatment of refractory SE with a success rate estimate of 57.9%. There are no known reported cases of concomitant use of vagus nerve stimulation (VNS) and ECT for the treatment of super refractory SE (SRSE) available in the literature.

CASE DESCRIPTION

We present a 44-year-old female with a history of developmental delay, epilepsy, an implantable VNS for 6 years, and traumatic brain injury with subsequent hygroma who presented with progressive aphasia, declining mental status, and daily generalized seizures lasting up to 20 min. Seizures had increased from her baseline of one seizure per day controlled with topiramate 200 mg three times daily and lamotrigine 400 mg twice daily. She was diagnosed with SRSE after being intubated and placed on eight anti-epileptic drugs (AEDs) that failed to abort SE. ECT was attempted to terminate SE. Due to a prior right craniotomy with subsequent right hygroma, eight treatments of ECT were performed over three sessions using a right anterior, left temporal (RALT) and subsequently a bitemporal electrode placement. The VNS remained active throughout treatment. Various ECT dosing parameters were attempted, varying pulse width and frequency. Although ECT induced mild transient encephalographic (EEG) changes following ECT stimulations, it was unable to terminate SE.

DISCUSSION

This case describes various treatment strategies, constraints, and device limitations when using ECT for the treatment of SE. With wide variability in efficacy rates of ECT in the treatment of SE in the literature, successful and unsuccessful cases offer information on optimizing ECT total charge dose and parameters that yielded success. This case demonstrates an instance of ECT inefficacy in the treatment of SRSE. Here, we discuss the rationale behind the various ECT settings that were selected, and constraints arising from the antiepileptic burden, VNS, and intrinsic limitations of the ECT device itself.

Super-refractory status epilepticus (SRSE): A case series of 22 pediatric patients

BACKGROUND

Super-refractory Status Epilepticus (SRSE) is a rare condition in which SE persists or recurs ≥24 h after the onset of anesthesia. Although its characteristics are well defined in adulthood, only few studies on children are available.

METHODS

we retrospectively analyzed the population of patients with SRSE aged <18 years treated in the Pediatric Intensive Care Unit of the Bambino Gesù Pediatric Hospital. We assessed clinical history, etiology, neuroimaging, electro-clinical features of SRSE, treatments and neurological status after SRSE cessation.

RESULTS

We identified 22 children with median age at SRSE onset of 3.1 years (IQR 1.3-7.3) and SRSE duration of 22.0 days (IQR 11.2-30.5) Before SRSE, 17 patients (77.3%) had an abnormal neurological examination, 18 (81.8%) had a diagnosis of epilepsy, 8 of which already presented an episode of SE. Only 4 patients (18.2%) had New Onset SRSE. Eleven patients had a progressive etiology (PE), 9 had a remote etiology (RE) and 2 patients had an acute etiology (AE). Amongst PE the most frequent etiologies were mitochondrial diseases, while among RE they were Developmental Epileptic Encephalopathies of genetic origin. Time to SRSE cessation was significantly longer in PE (p = 0.04). After SRSE, 8 patients, (7 with PE) showed a significant worsening of neurological status. In this group, mean time at SE cessation was significantly longer (p = 0.05).

CONCLUSIONS

pediatric SRSE is mostly associated with progressive diseases and remote etiologies. Underlying etiology seems to impact both on SRSE duration and subsequent neurological evolution, however more studies are needed to confirm these findings.

Pharmacotherapy for Nonconvulsive Seizures and Nonconvulsive Status Epilepticus

Most seizures in critically ill patients are nonconvulsive. A significant number of neurological and medical conditions can be complicated by nonconvulsive seizures (NCSs) and nonconvulsive status epilepticus (NCSE), with brain infections, hemorrhages, global hypoxia, sepsis, and recent neurosurgery being the most prominent etiologies. Prolonged NCSs and NCSE can lead to adverse neurological outcomes. Early recognition requires a high degree of suspicion and rapid and appropriate duration of continuous electroencephalogram (cEEG) monitoring. Although high quality research evaluating treatment with antiseizure medications and long-term outcome is still lacking, it is probable that expeditious pharmacological management of NCSs and NCSE may prevent refractoriness and further neurological injury. There is limited evidence on pharmacotherapy for NCSs and NCSE, although a few clinical trials encompassing both convulsive and NCSE have demonstrated similar efficacy of different intravenous (IV) antiseizure medications (ASMs), including levetiracetam, valproate, lacosamide and fosphenytoin. The choice of specific ASMs lies on tolerability and safety since critically ill patients frequently have impaired renal and/or hepatic function as well as hematological/hemodynamic lability. Treatment frequently requires more than one ASM and occasionally escalation to IV anesthetic drugs. When multiple ASMs are required, combining different mechanisms of action should be considered. There are several enteral ASMs that could be used when IV ASM options have been exhausted. Refractory NCSE is not uncommon, and its treatment requires a very judicious selection of ASMs aiming at reducing seizure burden along with management of the underlying condition.

Emergency management of the paediatric patient with convulsive status epilepticus

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

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

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

Antagomir-mediated suppression of microRNA-134 reduces kainic acid-induced seizures in immature mice

MicroRNAs are short non-coding RNAs that negatively regulate protein levels and perform important roles in establishing and maintaining neuronal network function. Previous studies in adult rodents have detected upregulation of microRNA-134 after prolonged seizures (status epilepticus) and demonstrated that silencing microRNA-134 using antisense oligonucleotides, termed antagomirs, has potent and long-lasting seizure-suppressive effects. Here we investigated whether targeting microRNA-134 can reduce or delay acute seizures in the immature brain. Status epilepticus was induced in 21 day-old (P21) male mice by systemic injection of 5 mg/kg kainic acid. This triggered prolonged electrographic seizures and select bilateral neuronal death within the CA3 subfield of the hippocampus. Expression of microRNA-134 and functional loading to Argonaute-2 was not significantly changed in the hippocampus after seizures in the model. Nevertheless, when levels of microRNA-134 were reduced by prior intracerebroventricular injection of an antagomir, kainic acid-induced seizures were delayed and less severe and mice displayed reduced neuronal death in the hippocampus. These studies demonstrate targeting microRNA-134 may have therapeutic applications for the treatment of seizures in children.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Top of Basilar Syndrome Presenting With Hyperekplexia Initially Diagnosed as a Convulsive Status Epilepticus

BACKGROUND

Hyperekplexia is a rare neurologic disorder characterized by pronounced startle responses to tactile or acoustic stimuli and increase tone. Acquired hyperekplexia is usually seen in brainstem pathologies and when it develops acutely it can be easily misdiagnosed as a convulsive seizure.

CASE REPORT

A 38-year-old man presented with acute onset generalized brief involuntary jerky movements and a decreased level of consciousness. He was initially diagnosed with convulsive status epilepticus for which he received multiple antiseizure medications without any improvement. Further investigations revealed abnormal oculocephalic reflex response and that his movements were in fact hyperkeplexia caused by brainstem infarction with basilar artery thrombus secondary to right vertebral artery dissection. Emergent thrombectomy was performed and he was eventually discharged to a rehabilitation facility. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians should be aware of hyperekplexia and how to differentiate it from convulsive stats epilepticus because the pathology and the emergent treatment of these 2 serious conditions are different. An underlying acquired brainstem pathology (especially basilar artery thromboembolism) should be suspected in any patient with untypical convulsive like movements along with focal neurologic signs compatible with brain stem pathology even when computed tomography imaging is normal. © 2020 Elsevier Inc.

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

BACKGROUND

Phenytoin is the current standard of care for second-line treatment of paediatric convulsive status epilepticus after failure of first-line benzodiazepines, but is only effective in 60% of cases and is associated with considerable adverse effects. A newer anticonvulsant, levetiracetam, can be given more quickly, is potentially more efficacious, and has a more tolerable adverse effect profile. We aimed to determine whether phenytoin or levetiracetam is the superior second-line treatment for paediatric convulsive status epilepticus.

METHODS

ConSEPT was an open-label, multicentre, randomised controlled trial conducted in 13 emergency departments in Australia and New Zealand. Children aged between 3 months and 16 years, with convulsive status epilepticus that failed first-line benzodiazepine treatment, were randomly assigned (1:1) using a computer-generated permuted block (block sizes 2 and 4) randomisation sequence, stratified by site and age (≤5 years, >5 years), to receive 20 mg/kg phenytoin (intravenous or intraosseous infusion over 20 min) or 40 mg/kg levetiracetam (intravenous or intraosseous infusion over 5 min). The primary outcome was clinical cessation of seizure activity 5 min after the completion of infusion of the study drug. Analysis was by intention to treat. This trial is registered with the Australian and New Zealand Clinical Trials Registry, number ACTRN12615000129583.

FINDINGS

Between March 19, 2015, and Nov 29, 2017, 639 children presented to participating emergency departments with convulsive status epilepticus; 127 were missed, and 278 did not meet eligibility criteria. The parents of one child declined to give consent, leaving 233 children (114 assigned to phenytoin and 119 assigned to levetiracetam) in the intention-to-treat population. Clinical cessation of seizure activity 5 min after completion of infusion of study drug occurred in 68 (60%) patients in the phenytoin group and 60 (50%) patients in the levetiracetam group (risk difference -9·2% [95% CI -21·9 to 3·5]; p=0·16). One participant in the phenytoin group died at 27 days because of haemorrhagic encephalitis; this death was not thought to be due to the study drug. There were no other serious adverse events.

INTERPRETATION

Levetiracetam is not superior to phenytoin for second-line management of paediatric convulsive status epilepticus.

FUNDING

Health Research Council of New Zealand, A+ Trust, Emergency Medicine Foundation, Townsville Hospital Private Practice Fund, Eric Ormond Baker Charitable Fund, and Princess Margaret Hospital Foundation.

Febrile infection-related epilepsy syndrome (FIRES): prevalence, impact and management strategies

Febrile infection-related epilepsy syndrome (FIRES) is a rare catastrophic epileptic encephalopathy with a yet undefined etiology, affecting healthy children. It is characterized by acute manifestation of recurrent seizures or refractory status epilepticus preceded by febrile illness, but without evidence of infectious encephalitis. To date, the absence of specific biomarkers poses a significant diagnostic challenge; nonetheless, early diagnosis is very important for optimal management. FIRES is mostly irreversible and its sequelae include drug-resistant epilepsy and neuropsychological impairments. The treatment of FIRES represents a significant challenge for clinicians and is associated with low success rates. Early introduction of ketogenic diet seems to represent the most effective and promising treatment. This review aims to highlight the most recent insights on clinical features, terminology, epidemiology, pathogenesis, diagnostic challenges and therapeutic options.

Fosphenytoin vs. continuous midazolam for pediatric febrile status epilepticus

BACKGROUND

Fosphenytoin (fPHT) and continuous intravenous midazolam (cMDL) had commonly been used as second-line treatments for pediatric status epilepticus (SE) in Japan. However, there is no comparative study of these two treatments.

METHODS

We included consecutive children who 1) were admitted to Kobe Children's Hospital because of convulsion with fever and 2) were treated with either fPHT or cMDL as second-line treatment for convulsive SE lasting for longer than 30 min. We compared, between the fPHT and cMDL groups, the proportion of barbiturate coma therapy (BCT), incomplete recovery of consciousness, mechanical ventilation, and inotropic agents.

RESULTS

The proportion of BCT was not significantly different between the two groups (48.7% [20/41] in fPHT and 35.3% [29/82] in cMDL, p = 0.17). The prevalence of incomplete recovery of consciousness, mechanical ventilation, and inotropic agents was not different between the two groups. After excluding 49 patients treated with BCT, incomplete recovery of consciousness 6 h and 12 h after onset was more frequent in the cMDL group than in the fPHT group (71.7% vs. 33.3%, p < 0.01; 56.6% vs. 14.2%, p < 0.01; respectively). Mechanical ventilation was more frequent in the cMDL group than in the fPHT group (32.0% vs. 4.7%, p = 0.01).

CONCLUSIONS

Our results suggest that 1) the efficacy of fPHT and cMDL is similar, although cMDL may prevent the need for BCT compared with fPHT, and 2) fPHT is relatively safe as a second-line treatment for pediatric SE in patients who do not require BCT.

Pediatric refractory and super-refractory status epilepticus

PURPOSE

To summarize the available evidence related to pediatric refractory status epilepticus (RSE) and super-refractory status epilepticus (SRSE), with emphasis on epidemiology, etiologies, therapeutic approaches, and clinical outcomes.

METHODS

Narrative review of the medical literature using MEDLINE database.

RESULTS

RSE is defined as status epilepticus (SE) that fails to respond to adequately used first- and second-line antiepileptic drugs. SRSE occurs when SE persist for 24 h or more after administration of anesthesia, or recurs after its withdrawal. RSE and SRSE represent complex neurological emergencies associated with long-term neurological dysfunction and high mortality. Challenges in management arise as the underlying etiology is not always promptly recognized and therapeutic options become limited with prolonged seizures. Treatment decisions mainly rely on case series or experts' opinions. The comparative effectiveness of different treatment strategies has not been evaluated in large prospective series or randomized clinical trials. Continuous infusion of anesthetic agents is the most common treatment for RSE and SRSE, although many questions on optimal dosing and rate of administration remain unanswered. The use of non-pharmacological therapies is documented in case series or reports with low level of evidence. In addition to neurological complications resulting from prolonged seizures, children with RSE/SRSE often develop systemic complications associated with polypharmacy and prolonged hospital stay.

CONCLUSION

RSE and SRSE are neurological emergencies with limited therapeutic options. Multi-national collaborative efforts are desirable to evaluate the safety and efficacy of current RSE/SRSE therapies, and potentially impact patients' outcomes.

Sodium valproate compared to phenytoin in treatment of status epilepticus

BACKGROUND

Status epilepticus (SE) is a neurological emergency which can be life-threatening. Several medical regimens are used in order to control it. In this study, we intended to evaluate the clinical efficacy and tolerability of sodium valproate and intravenous phenytoin (IV PHT) in the control of SE.

METHODS

One hundred and ten consecutive patients suffering from benzodiazepine refractory SE who were referred to the emergency ward from March 2014 to March 2015 were randomly divided into two groups. The first group received intravenous sodium valproate, 30 mg/kg as loading dose and then 4-8 mg/kg every 8 hr as maintenance regimen. The second group received IV PHT 20 mg/kg as loading dose and then 1.5 mg/kg for 8 hr as maintenance therapy. All patients were monitored for vital signs every 2 hr up to 12 hr. The patients were also followed up for 7 days regarding drug response and adverse effects.

RESULTS

The administration of sodium valproate and phenytoin respectively resulted in seizure control in 43 (78.18%) and 39 (70.90%) of the patients within 7 days of drug administration (p = .428). Seven-day mortality rate was similar in both groups (12.73% vs. 12.73%; p = .612). There was no significant difference in adverse effects between two groups.

CONCLUSION

Sodium valproate is preferred to IV PHT for treatment and control of SE due to its higher tolerability and lower hemodynamic instability.

Therapeutic burst-suppression coma in pediatric febrile refractory status epilepticus

BACKGROUND

Evidence for the beneficial effect of therapeutic burst-suppression coma in pediatric patients with febrile refractory status epilepticus is limited, and the clinical outcomes of this treatment strategy are largely unknown. Therefore, the aim of this study was to explore the outcomes of therapeutic burst-suppression coma in a series of children with febrile refractory status epilepticus.

METHODS

We retrospectively reviewed consecutive pediatric patients with febrile refractory status epilepticus admitted to our pediatric intensive care unit between January 2000 and December 2013. The clinical characteristics were analyzed.

RESULTS

Thirty-five patients (23 boys; age range: 1-18years) were enrolled, of whom 28 (80%) developed super-refractory status epilepticus. All of the patients received the continuous administration of intravenous antiepileptic drugs for febrile refractory status epilepticus, and 26 (74.3%) achieved therapeutic burst-suppression coma. All of the patients received mechanical ventilatory support, and 26 (74.3%) received inotropic agents. Eight (22.9%) patients died within 1month. The neurologically functional outcomes at 6months were good in six (27.3%) of the 22 survivors, of whom two returned to clinical baseline. The patients with therapeutic burst-suppression coma were significantly associated with hemodynamic support than the patients with electrographic seizures control (p=0.03), and had a trend of higher 1-month mortality rate, worse 6months outcomes, and a longer duration of hospitalization.

CONCLUSIONS

Our results suggest that therapeutic burst-suppression coma to treat febrile refractory status epilepticus may lead to an increased risk of hemodynamic instability and a trend of worse outcomes.

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.

A Comparison of Intravenous Levetiracetam and Valproate for the Treatment of Refractory Status Epilepticus in Children

Because of the lack of studies comparing the efficacy and safety of levetiracetam and valproate before the induction of general anesthesia in the treatment of convulsive refractory status epilepticus in children, we aimed to compare the effectiveness of these antiepileptic drugs in patients with convulsive status epilepticus admitted to the Pediatric Intensive Care Unit between 2011 and 2014. Forty-six (59%) of the 78 patients received levetiracetam, and 32 (41%) received valproate for the treatment of refractory status epilepticus. The response rate was not significantly different between the 2 groups. Although no adverse event was noted in patients who received levetiracetam, 4 (12.5%) patients in the valproate group experienced liver dysfunction (P = .025). According to our results, levetiracetam and valproate may be used in the treatment of refractory status epilepticus before the induction of general anesthesia. Levetiracetam appears as effective as valproate, and also safer.

Treatment of Established Status Epilepticus

Status epilepticus is the most severe form of epilepsy, with a high mortality rate and high health care costs. Status epilepticus is divided into four stages: early, established, refractory, and super-refractory. While initial treatment with benzodiazepines has become standard of care for early status epilepticus, treatment after benzodiazepine failure (established status epilepticus (ESE)) is incompletely studied. Effective treatment of ESE is critical as morbidity and mortality increases dramatically the longer convulsive status epilepticus persists. Phenytoin/fosphenytoin, valproic acid, levetiracetam, phenobarbital, and lacosamide are the most frequently prescribed antiseizure medications for treatment of ESE. To date there are no class 1 data to support pharmacologic recommendations of one agent over another. We review each of these medications, their pharmacology, the scientific evidence in support and against each in the available literature, adverse effects and safety profiles, dosing recommendations, and limitations of the available evidence. We also discuss future directions including the established status epilepticus treatment trial (ESETT). Substantial further research is urgently needed to identify these patients (particularly those with non-convulsive status epilepticus), elucidate the most efficacious antiseizure treatment with head-to-head randomized prospective trials, and determine whether this differs for convulsive vs. non-convulsive ESE.

Management of Status Epilepticus in Children

Status epilepticus is a common pediatric neurological emergency. Management includes prompt administration of appropriately selected anti-seizure medications, identification and treatment of seizure precipitant(s), as well as identification and management of associated systemic complications. This review discusses the definitions, classification, epidemiology and management of status epilepticus and refractory status epilepticus in children.

Emerging roles of Na⁺/H⁺ exchangers in epilepsy and developmental brain disorders

Epilepsy is a common central nervous system (CNS) disease characterized by recurrent transient neurological events occurring due to abnormally excessive or synchronous neuronal activity in the brain. The CNS is affected by systemic acid-base disorders, and epileptic seizures are sensitive indicators of underlying imbalances in cellular pH regulation. Na(+)/H(+) exchangers (NHEs) are a family of membrane transporter proteins actively involved in regulating intracellular and organellar pH by extruding H(+) in exchange for Na(+) influx. Altering NHE function significantly influences neuronal excitability and plays a role in epilepsy. This review gives an overview of pH regulatory mechanisms in the brain with a special focus on the NHE family and the relationship between epilepsy and dysfunction of NHE isoforms. We first discuss how cells translocate acids and bases across the membrane and establish pH homeostasis as a result of the concerted effort of enzymes and ion transporters. We focus on the specific roles of the NHE family by detailing how the loss of NHE1 in two NHE mutant mice results in enhanced neuronal excitability in these animals. Furthermore, we highlight new findings on the link between mutations of NHE6 and NHE9 and developmental brain disorders including epilepsy, autism, and attention deficit hyperactivity disorder (ADHD). These studies demonstrate the importance of NHE proteins in maintaining H(+) homeostasis and their intricate roles in the regulation of neuronal function. A better understanding of the mechanisms underlying NHE1, 6, and 9 dysfunctions in epilepsy formation may advance the development of new epilepsy treatment strategies.

Chronological Evolution of Magnetic Resonance Imaging Findings in Children With Febrile Infection-Related Epilepsy Syndrome

OBJECTIVE

To describe and analyze the chronological evolution of the radiological findings in seven children with febrile infection-related epilepsy syndrome.

METHODS

This is a retrospective study describing the radiological findings and evolution in seven children with febrile infection-related epilepsy syndrome who presented from 2009 to 2013. The children all fit the defined clinical criteria for febrile infection-related epilepsy syndrome; all had a history of normal psychomotor development who presented with acute-onset catastrophic partial status epilepticus associated with a febrile illness or unspecific infectious process. The children were identified from the author's weekly review of the pediatric inpatient service, and then the data were collected and analyzed retrospectively.

RESULTS

Six males and one female ranging from 3 months to 9 years of age presented with status epilepticus preceded by a febrile illness. Extensive investigations for infectious, autoimmune, and metabolic etiologies were unremarkable. Multiple antiepileptic medications were attempted, including drug-induced coma in all of them, with poor response. Immunotherapy with intravenous steroids or intravenous immunoglobulin (three patients had both) was tried in six of seven patients with a poor response. Ketogenic diet was initiated in four of seven patients with limited response. Serial magnetic resonance imaging studies, done from the initial presentation through 18 months of follow-up, showed evolution from normal imaging to severe cerebral atrophy. Progressive cytotoxic edema involving mostly bilateral hippocampi and temporal lobes was appreciated in one to three weeks. At one month from seizure onset, mild to moderate cerebral atrophy and hippocampal sclerosis was appreciated that continued to progress over the next year. After six to twelve months, most of the patients showed moderate to severe cerebral atrophy and by one year, cerebellar atrophy was also appreciated.

CONCLUSION

Febrile infection-related epilepsy syndrome is a devastating epilepsy syndrome of childhood without a diagnostic biologic marker. The magnetic resonance imaging findings appear to be progressive and typical. Thus, combined with the clinical course, imaging findings can help to confirm the diagnosis (until a biologic marker is found). This hopefully will allow multicentered treatment protocols in the future.