Treatment of pediatric status epilepticus

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.

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.

Levetiracetam versus Fosphenytoin in Pediatric Convulsive Status Epilepticus: A Randomized Controlled Trial

Objectives:

The aim of this study was to compare the efficacy and safety of intravenous levetiracetam and fosphenytoin in the management of pediatric status epilepticus.

Materials and Methods:

This is an open-labeled randomized controlled trial, conducted at tertiary care pediatric intensive care unit. Subjects between 1 month and 18 years who presented with status epilepticus were enrolled. If seizures persisted even after two doses of lorazepam, participants were randomized to receive either fosphenytoin 30 mg/kg or levetiracetam 30 mg/kg intravenously and followed up till 48h, for seizure recurrence and adverse drug effects. Outcome measures were cessation of seizures within 10–20 min following the end of the infusion of drugs fosphenytoin and levetiracetam, respectively, and no recurrence of seizures was noted over next 48h.

Results:

Subjects in both study groups were comparable in baseline characteristics. Seizures stopped in 54 (93.1%) and 53 (91.4%) in fosphenytoin and levetiracetam groups, respectively (P = 1.000). Seizure recurrence was noted in 13 (22.4%) and 10 (17.2%) patients in fosphenytoin and levetiracetam groups, respectively (n = 0.485). In fosphenytoin group, one (1.7%) child had bradycardia, two (3.4%) children required inotropes, and three (5.2%) children required intubation. In levetiracetam group, none had bradyarrhythmia, required inotropes, and intubation was required in one (1.7%) child each. No statistically significant difference was observed in outcome parameters in two groups.

Conclusion:

Levetiracetam is as efficacious as fosphenytoin in control of pediatric status epilepticus and is associated with lesser side effects.

First-line medication dosing in pediatric refractory status epilepticus

OBJECTIVE

To identify factors associated with low benzodiazepine (BZD) dosing in patients with refractory status epilepticus (RSE) and to assess the impact of BZD treatment variability on seizure cessation.

METHODS

This was a retrospective study with prospectively collected data of children with convulsive RSE admitted between June 2011 and January 2019. We analyzed the initial and total BZD dose within 10 minutes of treatment initiation. We used logistic regression modeling to evaluate predictors of low BZD dosing and multivariate Cox regression analysis to assess the impact of low BZD dosing on time to seizure cessation.

RESULTS

We included 289 patients (55.7% male) with a median age of 4.3 (1.3-9.5) years. BZDs were the initial medication in 278 (96.2%). Of those, 161 patients (57.9%) received a low initial dose. Low initial BZD doses occurred in both out-of-hospital (57 of 106; 53.8%) and in-hospital (104 of 172; 60.5%) settings. One hundred three patients (37.1%) received low total BZD dose. Male sex (odds ratio [OR] 2, 95% confidence interval [CI] 1.18-3.49; p = 0.012), older age (OR 1.1, 95% CI 1.05-1.17; p < 0.001), no prior diagnosis of epilepsy (OR 2.1, 95% CI 1.23-3.69; p = 0.008), and delayed BZD treatment (OR 2.2, 95% CI 1.24-3.94; p = 0.007) were associated with low total BZD dose. Patients who received low total BZD dosing were less likely to achieve seizure cessation (hazard ratio 0.7, 95% CI 0.57-0.95).

CONCLUSION

BZD doses were lower than recommended in both out-of-hospital and in-hospital settings. Factors associated with low total BZD dose included male sex, older age, no prior epilepsy diagnosis, and delayed BZD treatment. Low total BZD dosing was associated with decreased likelihood of Seizure cessation.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that patients with RSE who present with male sex, older age, no prior diagnosis of epilepsy, and delayed BZD treatment are more likely to receive low total BZD doses. This study provides Class III evidence that in pediatric RSE low total BZD dose decreases the likelihood of seizure cessation.

Evaluation of fosphenytoin, levetiracetam, and propofol as treatments for nerve agent-induced seizures in pediatric and adult rats

Multiple recent instances of nerve agent (NA) exposure in civilian populations have occurred, resulting in a variety of negative effects and lethality in both adult and pediatric populations. Seizures are a prominent effect of NAs that can result in neurological damage and contribute to their lethality. Current anticonvulsant treatments for NAs are approved for adults, but no approved pediatric treatments exist. Further, the vast majority of NA-related research in animals has been conducted in adult male subjects. There is a need for research that includes female and pediatric populations in testing. In this project, adult and pediatric male and female rats were challenged with sarin or VX and then treated with fosphenytoin, levetiracetam, or propofol. In this study, fosphenytoin and levetiracetam failed to terminate seizure activity when animals were treated 5 min after seizure onset. Propofol was effective, exhibiting high efficacy and potency for terminating seizure activity quickly in pediatric and adult animals, suggesting it may be an effective anticonvulsant for NA-induced seizures in pediatric populations.

Pharmacotherapy for Pediatric Convulsive Status Epilepticus

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

Conventional and quantitative EEG in status epilepticus

PURPOSE

To summarize the use of continuous electroencephalographic monitoring (cEEG) in the diagnosis and management of pediatric convulsive status epilepticus (CSE) and subsequent non-convulsive seizures (NCS) with a focus on available guidelines and infrastructure. In addition, we provide an overview of quantitative EEG (QEEG) for the identification of NCS in critically ill children.

METHODS

We performed a review of the medical literature on the use of cEEG and QEEG in pediatric CSE. This included published guideline, consensus statements, and literature focused on the use of cEEG and QEEG to detect NCS.

RESULTS

cEEG monitoring is recommended for prompt recognition of ongoing seizures that may be subtle, masked by pharmacologic paralysis, and or converted from convulsive seizures to NCS after administration of anti-seizure medications. Evidence indicating that high seizure burden is associated with worse outcome has motivated prompt recognition and management of NCS. The American Clinical Neurophysiology Society's consensus statement recommends a minimum of 24 h to exclude electrographic seizures, while the Neurocritical Care Society's guideline suggests 48 h in patients that are comatose. The use of QEEG amongst electroencephalographers and critical care medicine providers is increasing for NCS detection in critically ill children. The sensitivity and specificity of QEEG to detect NCS ranges from 65 to 83% and 65-92%, respectively.

CONCLUSION

The use of cEEG is important to the diagnosis and treatment of NCS or subtle clinical seizures after pediatric CSE. QEEG allows cEEG data to be reviewed and interpreted quickly and is a useful tool for detection of NCS after CSE.

Long-term outcomes of status epilepticus: A critical assessment

We reviewed 37 studies reporting long-term outcomes after a status epilepticus (SE) episode in pediatric and adult populations. Study design, length of follow-up, outcome measures, domains investigated (mortality, SE recurrence, subsequent epilepsy, cognitive outcome, functional outcome, or quality of life), and predictors of long-term outcomes are summarized. Despite heterogeneity in the design of prior studies, overall risk of poor long-term outcome after SE is high in both children and adults. Etiology is the main determinant of outcome, and the effect of age or SE duration is often difficult to distinguish from the underlying cause. The effect of the treatment on long-term outcome after SE is still unknown.

Hospital Emergency Treatment of Convulsive Status Epilepticus: Comparison of Pathways From Ten Pediatric Research Centers

OBJECTIVE

We aimed to evaluate and compare the status epilepticus treatment pathways used by pediatric status epilepticus research group (pSERG) hospitals in the United States and the American Epilepsy Society (AES) status epilepticus guideline.

METHODS

We undertook a descriptive analysis of recommended timing, dosing, and medication choices in 10 pSERG hospitals' status epilepticus treatment pathways.

RESULTS

One pathway matched the timeline in the AES guideline; nine pathways described more rapid timings. All pathways matched the guideline's stabilization phase in timing and five suggested that first-line benzodiazepine (BZD) be administered within this period. For second-line therapy timing (initiation of a non-BZD antiepileptic drug within 20 to 40 minutes), one pathway matched the guideline; nine initiated the antiepileptic drug earlier (median 10 [range five to 15] minutes). Third-line therapy timings matched the AES guideline (40 minutes) in two pathways; eight suggested earlier timing (median 20 [range 15 to 30] minutes). The first-line BZD recommended in all hospitals was intravenous lorazepam; alternatives included intramuscular midazolam or rectal diazepam. In second-line therapy, nine pathways recommended fosphenytoin. For third-line therapy, eight pathways recommended additional boluses of second-line medications; most commonly phenobarbital. Two pathways suggested escalation to third-line medication; most commonly midazolam. We found variance in dosing for the following medications: midazolam as first-line therapy, fosphenytoin, and levetiracetam as second-line therapy, and phenobarbital as third-line therapy medications.

CONCLUSIONS

The pSERG hospitals status epilepticus pathways are consistent with the AES status epilepticus guideline in regard to the choice of medications, but generally recommend more rapid escalation in therapy than the guideline.

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.

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.

The Effect of Quercetin on Pro- and Anti-Inflammatory Cytokines in a Prenatally Stressed Rat Model of Febrile Seizures

Febrile seizures are childhood convulsions resulting from an infection that leads to an inflammatory response and subsequent convulsions. Prenatal stress has been shown to heighten the progression and intensity of febrile seizures. Current medications are costly and have adverse effects associated with prolonged use. Quercetin flavonoid exhibits anti-inflammatory, anti-convulsant, and anti-stress effects. This study was aimed to investigate the therapeutic effect of quercetin in a prenatally stressed rat model of febrile seizures. We hypothesized that quercetin will alleviate the effects of prenatal stress in a febrile seizure rat model. On gestational day 13, Sprague-Dawley rat dams were subjected to restraint stress for 1 hour/d for 7 days. Febrile seizures were induced on postnatal day 14 on rat pups by intraperitoneally injecting lipopolysaccharide followed by kainic acid and quercetin on seizure onset. Hippocampal tissue was harvested to profile cytokine concentrations. Our results show that quercetin suppresses prenatal stress–induced pro-inflammatory marker (interleukin 1 beta) levels, subsequently attenuating febrile seizures. This shows that quercetin can be therapeutic for febrile seizures in prenatally stressed individuals.

Refractory status epilepticus in children with and without prior epilepsy or status epilepticus

OBJECTIVE

To compare refractory convulsive status epilepticus (rSE) management and outcome in children with and without a prior diagnosis of epilepsy and with and without a history of status epilepticus (SE).

METHODS

This was a prospective observational descriptive study performed from June 2011 to May 2016 on pediatric patients (1 month-21 years of age) with rSE.

RESULTS

We enrolled 189 participants (53% male) with a median (25th-75th percentile) age of 4.2 (1.3-9.6) years. Eighty-nine (47%) patients had a prior diagnosis of epilepsy. Thirty-four (18%) patients had a history of SE. The time to the first benzodiazepine was similar in participants with and without a diagnosis of epilepsy (15 [5-60] vs 16.5 [5-42.75] minutes, p = 0.858). Patients with a diagnosis of epilepsy received their first non-benzodiazepine (BZD) antiepileptic drug (AED) later (93 [46-190] vs 50.5 [28-116] minutes, p = 0.002) and were less likely to receive at least one continuous infusion (35/89 [39.3%] vs 57/100 [57%], p = 0.03). Compared to patients with no history of SE, patients with a history of SE received their first BZD earlier (8 [3.5-22.3] vs 20 [5-60] minutes, p = 0.0073), although they had a similar time to first non-BZD AED (76.5 [45.3-124] vs 65 [32.5-156] minutes, p = 0.749). Differences were mostly driven by the patients with an out-of-hospital rSE onset.

CONCLUSIONS

Our study establishes that children with rSE do not receive more timely treatment if they have a prior diagnosis of epilepsy; however, a history of SE is associated with more timely administration of abortive medication.

Treatment of drug-induced seizures

Seizures are a common complication of drug intoxication, and up to 9% of status epilepticus cases are caused by a drug or poison. While the specific drugs associated with drug-induced seizures may vary by geography and change over time, common reported causes include antidepressants, stimulants and antihistamines. Seizures occur generally as a result of inadequate inhibitory influences (e.g., gamma aminobutyric acid, GABA) or excessive excitatory stimulation (e.g. glutamate) although many other neurotransmitters play a role. Most drug-induced seizures are self-limited. However, status epilepticus occurs in up to 10% of cases. Prolonged or recurrent seizures can lead to serious complications and require vigorous supportive care and anticonvulsant drugs. Benzodiazepines are generally accepted as the first line anticonvulsant therapy for drug-induced seizures. If benzodiazepines fail to halt seizures promptly, second line drugs include barbiturates and propofol. If isoniazid poisoning is a possibility, pyridoxine is given. Continuous infusion of one or more anticonvulsants may be required in refractory status epilepticus. There is no role for phenytoin in the treatment of drug-induced seizures. The potential role of ketamine and levetiracetam is promising but not established.

Etiology, clinical course and response to the treatment of status epilepticus in children: A 16-year single-center experience based on 602 episodes of status epilepticus

OBJECTIVE

evaluation of etiology, clinical course and response to the treatment of status epilepticus (SE) in children, with particular investigation of superrefractory SE.

MATERIALS AND METHODS

The retrospective study included children with convulsive SE aged 0.2-18 years, treated from 1995 to 2011. Status epilepticus is defined as a continuous seizure or intermittent seizures without full recovery of consciousness between seizures for at least 30 min. Refractory SE is diagnosed if SE lasts for more than 60 min, while superrefractory SE if SE continues or recurs 24 h or more after the onset of an anesthesia therapy, including those cases that recur after reduction or withdrawal of an anesthesia. The etiology was summarized in five categories: idiopathic/cryptogenic, remote symptomatic, febrile SE, acute symptomatic and progressive encephalopathy. The patients were treated according to the same hospital protocol. Midazolam iv and diazepam rectally were given as the first line drugs, phenobarbital/phenytoin iv as the second line drugs. If they failed, third line drugs, midazolam and thiopental were given in continuous intravenous infusion. The medication was defined as effective if seizure clinically stopped within 20 min, without recurrence within the next 6 h. Midazolam was assessed as effective even if it failed as the first line, but was effective in intravenous infusion as the third line drug.

RESULTS

The study consisted of 602 SE in 395 children. There were 305 (50.7%) refractory SE episodes, and 43 (7.1%) of superrefractory SE. Idiopathic/cryptogenic and febrile SE was the most common etiology in the first SE, while progressive encephalopathy and remote symptomatic was in recurrent and superrefractory SE. The most effective drugs were: midazolam (306/339) given in mean dose of 0.4 mg/kg (range 0.1-1.2 mg/kg), thiopental (47/57) in mean dose of 4 mg/kg (range 3-5 mg/kg), phenobarbital (91/135) in dose of 20 mg/kg. Midazolam successfully stopped 306/339 SE episodes (90.3%), 67 SE (21.9%) by equal or lower dose than 0.2 mg/kg as the first line drug, while all other 239 episodes (78.9%) were stopped by intravenous infusion in range 0.2-1.2 mg/kg/h (mean 0.4 mg/kg/h) as the third line drug. Adverse effects were frequent in superrefractory SE (60.5%). In 15 patients, corticosteroids contributed to the reduction of seizure recurrence after anesthetic withdrawal and cessation of epilepsia partialis continua. Case fatality rate was 5.1% in all patients, while 21.3% in patients with superrefractory SE.

CONCLUSION

Status epilepticus in children was characterized by heterogeneous etiology, prolonged duration and commonly good response to midazolam only given in high doses. Superrefractory SE was not so rare in children, especially among the patients with progressive encephalopathy.

Time from convulsive status epilepticus onset to anticonvulsant administration in children

OBJECTIVE

To describe the time elapsed from onset of pediatric convulsive status epilepticus (SE) to administration of antiepileptic drug (AED).

METHODS

This was a prospective observational cohort study performed from June 2011 to June 2013. Pediatric patients (1 month-21 years) with convulsive SE were enrolled. In order to study timing of AED administration during all stages of SE, we restricted our study population to patients who failed 2 or more AED classes or needed continuous infusions to terminate convulsive SE.

RESULTS

We enrolled 81 patients (44 male) with a median age of 3.6 years. The first, second, and third AED doses were administered at a median (p25-p75) time of 28 (6-67) minutes, 40 (20-85) minutes, and 59 (30-120) minutes after SE onset. Considering AED classes, the initial AED was a benzodiazepine in 78 (96.3%) patients and 2 (2-3) doses of benzodiazepines were administered before switching to nonbenzodiazepine AEDs. The first and second doses of nonbenzodiazepine AEDs were administered at 69 (40-120) minutes and 120 (75-296) minutes. In the 64 patients with out-of-hospital SE onset, 40 (62.5%) patients did not receive any AED before hospital arrival. In the hospital setting, the first and second in-hospital AED doses were given at 8 (5-15) minutes and 16 (10-40) minutes after SE onset (for patients with in-hospital SE onset) or after hospital arrival (for patients with out-of-hospital SE onset).

CONCLUSIONS

The time elapsed from SE onset to AED administration and escalation from one class of AED to another is delayed, both in the prehospital and in-hospital settings.

Therapeutic choices in convulsive status epilepticus

INTRODUCTION

Convulsive status epilepticus (SE) is one of the most frequent and severe neurological emergencies in both adults and children. A timely administration of appropriate antiepileptic drugs (AEDs) can stop seizures early and markedly improve outcome.

AREAS COVERED

The main treatment strategies for SE are reviewed with an emphasis on initial treatments. The established first-line treatment consists of benzodiazepines, most frequently intravenous lorazepam. Benzodiazepines that do not require intravenous administration like intranasal midazolam or intramuscular midazolam are becoming more popular because of easier administration in the field. Other benzodiazepines may also be effective. After treatment with benzodiazepines, treatment with fosphenytoin and phenobarbital is usually recommended. Other intravenously available AEDs, such as valproate and levetiracetam, may be as effective and safe as fosphenytoin and phenobarbital, have a faster infusion time and better pharmacokinetic profile. The rationale behind the need for an early treatment of SE is discussed. The real-time delays of AED administration in clinical practice are described.

EXPERT OPINION

There is limited evidence to support what the best initial benzodiazepine or the best non-benzodiazepine AED is. Recent and developing multicenter trials are evaluating the best treatment options and will likely modify the recommended treatment choices in SE in the near future. Additionally, more research is needed to understand how different treatment options modify prognosis in SE. Timely implementation of care protocols to minimize treatment delays is crucial.

Effects of JAK2-STAT3 signaling after cerebral insults

The JAK2-STAT3 signaling pathway has been shown to regulate the expression of genes involved in cell survival, cell proliferation, cell-cycle progression, and angiogenesis in development and after cerebral insults. Until recently, little has been known about the effects of this pathway activation after cerebral insults and if blocking this pathway leads to better recovery. This review exams the role of this pathway after 3 cerebral insults (traumatic brain injury, stroke, and status epilepticus).

Intramuscular midazolam versus intravenous diazepam for treatment of seizures in the pediatric emergency department: a randomized clinical trial

AIM

To compare the therapeutic efficacy of intramuscular midazolam (MDZ-IM) with that of intravenous diazepam (DZP-IV) for seizures in children.

DESIGN

Randomized clinical trial.

SETTING

Pediatric emergency department.

PATIENTS

Children aged 2 months to 14 years admitted to the study facility with seizures.

INTERVENTION

Patients were randomized to receive DZP-IV or MDZ-IM.

MAIN MEASUREMENTS

Groups were compared with respect to time to treatment start (min), time from drug administration to seizure cessation (min), time to seizure cessation (min), and rate of treatment failure. Treatment was considered successful when seizure cessation was achieved within 5min of drug administration.

RESULTS

Overall, 32 children (16 per group) completed the study. Intravenous access could not be obtained within 5min in four patients (25%) in the DZP-IV group. Time from admission to active treatment and time to seizure cessation was shorter in the MDZ-IM group (2.8 versus 7.4min; p<0.001 and 7.3 versus 10.6min; p=0.006, respectively). In two children per group (12.5%), seizures continued after 10min of treatment, and additional medications were required. There were no between-group differences in physiological parameters or adverse events (p=0.171); one child (6.3%) developed hypotension in the MDZ-IM group and five (31%) developed hyperactivity or vomiting in the DZP-IV group.

CONCLUSION

Given its efficacy and ease and speed of administration, intramuscular midazolam is an excellent option for treatment of childhood seizures, enabling earlier treatment and shortening overall seizure duration. There were no differences in complications when applying MDZ-IM or DZP-IV.

P2X7 receptor inhibition interrupts the progression of seizures in immature rats and reduces hippocampal damage

AIMS

Early-life seizures, particularly when prolonged, may be harmful to the brain. Current pharmacotherapy is often ineffective; therefore, novel neuro- and/or glio-transmitter systems should be explored for targeting. The P2X7 receptor is a cation-permeable channel with trophic and excitability effects on neurons and glia which is activated by high amounts of ATP that may be released in the setting of injury after severe seizures. Here, we tested the effects of A-438079, a potent and selective P2X7 receptor antagonist in a lesional model of early-life status epilepticus.

METHODS

Seizures were induced by intra-amygdala kainic acid in 10-day-old rat pups. Electrographic seizure severity, changes to P2X7 receptor expression, inflammatory responses and histological effects were evaluated.

RESULTS

Seizures induced by intra-amygdala kainic acid increased levels of P2X7 receptor protein and interleukin-1β and caused significant cell death within the ipsilateral hippocampus. A-438079 rapidly reached the brain following systemic injection in P10 rats. Intraperitoneal injection of A-438079 (5 and 15 mg/kg) 60 min after triggering seizures reduced seizure severity and neuronal death within the hippocampus. A-438079 had superior neuroprotective effects compared with an equally seizure-suppressive dose of phenobarbital (25 mg/kg).

CONCLUSIONS

These results suggest P2X7 receptor antagonists may be suitable as frontline or adjunctive treatments of pediatric status epilepticus or other early-life seizures, particularly when associated with brain damage.

Electrographic seizures after convulsive status epilepticus in children and young adults: a retrospective multicenter study

OBJECTIVE

To describe the prevalence, characteristics, and predictors of electrographic seizures after convulsive status epilepticus (CSE).

STUDY DESIGN

This was a multicenter retrospective study in which we describe clinical and electroencephalographic (EEG) features of children (1 month to 21 years) with CSE who underwent continuous EEG monitoring.

RESULTS

Ninety-eight children (53 males) with CSE (median age of 5 years) underwent subsequent continuous EEG monitoring after CSE. Electrographic seizures (with or without clinical correlate) were identified in 32 subjects (33%). Eleven subjects (34.4%) had electrographic-only seizures, 17 subjects (53.1%) had electroclinical seizures, and 4 subjects (12.5%) had an unknown clinical correlate. Of the 32 subjects with electrographic seizures, 15 subjects (46.9%) had electrographic status epilepticus. Factors associated with the occurrence of electrographic seizures after CSE were a previous diagnosis of epilepsy (P = .029) and the presence of interictal epileptiform discharges (P < .0005). The median (p25-p75) duration of stay in the pediatric intensive care unit was longer for children with electrographic seizures than for children without electrographic seizures (9.5 [3-22.5] vs 2 [2-5] days, Wilcoxon test, Z = 3.916, P = .0001). Four children (4.1%) died before leaving the hospital, and we could not identify a relationship between death and the presence or absence of electrographic seizures.

CONCLUSIONS

After CSE, one-third of children who underwent EEG monitoring experienced electrographic seizures, and among these, one-third experienced entirely electrographic-only seizures. A previous diagnosis of epilepsy and the presence of interictal epileptiform discharges were risk factors for electrographic seizures.

Shake, rattle, and roll: an update on pediatric seizures

Seizure is a common presenting complaint for patients in the pediatric emergency department (PED) setting. In some cases, protocols are in place on how to manage this group of patients, for example, a patient with a simple febrile seizure already back to baseline or a patient with known epilepsy already back to baseline. However, many scenarios present dilemmas for physicians in the PED, specifically patients with status epilepticus (SE). Unfortunately, there is not a national SE protocol, and hospital-specific guidelines may or may not exist. Current practices are constantly changing because new medications arise, and more information is gathered regarding existing medications and guidelines. Here we will review the basics about first-time afebrile seizures presenting to the PED and common treatments specific to seizure types. We will then review SE management basics and medical therapy, including both older and newer agents and their routes of administration for both the prehospital and the hospital setting.

The established status epilepticus trial 2013

Benzodiazepine-refractory status epilepticus (established status epilepticus, ESE) is a relatively common emergency condition with several widely used treatments. There are no controlled, randomized, blinded clinical trials to compare the efficacy and tolerability of currently available treatments for ESE. The ESE treatment trial is designed to determine the most effective and/or the least effective treatment of ESE among patients older than 2 years by comparing three arms: fosphenytoin (fPHT) levetiracetam (LVT), and valproic acid (VPA). This is a multicenter, randomized, double-blind, Bayesian adaptive, phase III comparative effectiveness trial. Up to 795 patients will be randomized initially 1:1:1, and response-adaptive randomization will occur after 300 patients have been recruited. Randomization will be stratified by three age groups, 2-18, 19-65, and 66 and older. The primary outcome measure is cessation of clinical seizure activity and improving mental status, without serious adverse effects or further intervention at 60 min after administration of study drug. Each subject will be followed until discharge or 30 days from enrollment. This trial will include interim analyses for early success and futility. This trial will be considered a success if the probability that a treatment is the most effective is >0.975 or the probability that a treatment is the least effective is >0.975 for any treatment. Proposed total sample size is 795, which provides 90% power to identify the most effective and/or the least effective treatment when one treatment arm has a true response rate of 65% and the true response rate is 50% in the other two arms.

Gaps and opportunities in refractory status epilepticus research in children: a multi-center approach by the Pediatric Status Epilepticus Research Group (pSERG)

PURPOSE

Status epilepticus (SE) is a life-threatening condition that can be refractory to initial treatment. Randomized controlled studies to guide treatment choices, especially beyond first-line drugs, are not available. This report summarizes the evidence that guides the management of refractory convulsive SE (RCSE) in children, defines gaps in our clinical knowledge and describes the development and works of the 'pediatric Status Epilepticus Research Group' (pSERG).

METHODS

A literature review was performed to evaluate current gaps in the pediatric SE and RCSE literature. In person and online meetings helped to develop and expand the pSERG network.

RESULTS

The care of pediatric RCSE is largely based on extrapolations of limited evidence derived from adult literature and supplemented with case reports and case series in children. No comparative effectiveness trials have been performed in the pediatric population. Gaps in knowledge include risk factors for SE, biomarkers of SE and RCSE, second- and third-line treatment options, and long-term outcome.

CONCLUSION

The care of children with RCSE is based on limited evidence. In order to address these knowledge gaps, the multicenter pSERG was established to facilitate prospective collection, analysis, and sharing of de-identified data and biological specimens from children with RCSE. These data will allow identification of treatment strategies associated with better outcomes and delineate evidence-based interventions to improve the care of children with SE.

Autoimmune status epilepticus

OPINION STATEMENT

Autoimmune status epilepticus is a rare condition but one that has been increasingly recognized by neurologists and clinicians in the intensive care unit. As more cases are described in the literature and more antibody tests become commercially available, diagnosis is now feasible; however, early diagnosis remains a challenge. For practical purposes, status epilepticus may be considered as possibly autoimmune if it is refractory to anticonvulsant treatment and there is no other known cause; this may then lead to empiric immunomodulatory therapy. Major factors that raise the index of suspicion are recent cognitive or behavioral alterations, a history of malignancy or tumor, or presence of other neurological features. There is a lack of high level evidence in the literature for treatment of status epilepticus, and almost none for autoimmune encephalitis. Patients with autoimmune status epilepticus may be treated with immunomodulatory therapy, including steroids, intravenous immunoglobulin (IVIG), plasmapheresis (PLEX), and other immunosuppressive agents while maximizing their anticonvulsant therapy. For some patients, resective surgery may be necessary, such as hemispherectomy for Rasmussen's encephalopathy. In the case of status epilepticus due to paraneoplastic autoantibodies, urgent and aggressive testing and treatment of a primary malignancy is needed. Importantly, any suspicion of autoimmune mediated status epilepticus should prompt the transfer of the patient to a specialized center with experience in refractory status epilepticus whenever possible.