Treatment of Convulsive Status Epilepticus

ACVIM Consensus Statement on the management of status epilepticus and cluster seizures in dogs and cats

BACKGROUND

Seizure emergencies (ie, status epilepticus [SE] and cluster seizures [CS]), are common challenging disorders with complex pathophysiology, rapidly progressive drug-resistant and self-sustaining character, and high morbidity and mortality. Current treatment approaches are characterized by considerable variations, but official guidelines are lacking.

OBJECTIVES

To establish evidence-based guidelines and an agreement among board-certified specialists for the appropriate management of SE and CS in dogs and cats.

ANIMALS

None.

MATERIALS AND METHODS

A panel of 5 specialists was formed to assess and summarize evidence in the peer-reviewed literature with the aim to establish consensus clinical recommendations. Evidence from veterinary pharmacokinetic studies, basic research, and human medicine also was used to support the panel's recommendations, especially for the interventions where veterinary clinical evidence was lacking.

RESULTS

The majority of the evidence was on the first-line management (ie, benzodiazepines and their various administration routes) in both species. Overall, there was less evidence available on the management of emergency seizure disorders in cats in contrast to dogs. Most recommendations made by the panel were supported by a combination of a moderate level of veterinary clinical evidence and pharmacokinetic data as well as studies in humans and basic research studies.

CONCLUSIONS AND CLINICAL RELEVANCE

Successful management of seizure emergencies should include an early, rapid, and stage-based treatment approach consisting of interventions with moderate to preferably high ACVIM recommendations; management of complications and underlying causes related to seizure emergencies should accompany antiseizure medications.

Treatment of Status Epilepticus after Traumatic Brain Injury Using an Antiseizure Drug Combined with a Tissue Recovery Enhancer Revealed by Systems Biology

We tested a hypothesis that in silico-discovered compounds targeting traumatic brain injury (TBI)-induced transcriptomics dysregulations will mitigate TBI-induced molecular pathology and augment the effect of co-administered antiseizure treatment, thereby alleviating functional impairment. In silico bioinformatic analysis revealed five compounds substantially affecting TBI-induced transcriptomics regulation, including calpain inhibitor, chlorpromazine, geldanamycin, tranylcypromine, and trichostatin A (TSA). In vitro exposure of neuronal-BV2-microglial co-cultures to compounds revealed that TSA had the best overall neuroprotective, antioxidative, and anti-inflammatory effects. In vivo assessment in a rat TBI model revealed that TSA as a monotherapy (1 mg/kg/d) or in combination with the antiseizure drug levetiracetam (LEV 150 mg/kg/d) mildly mitigated the increase in plasma levels of the neurofilament subunit pNF-H and cortical lesion area. The percentage of rats with seizures during 0-72 h post-injury was reduced in the following order: TBI-vehicle 80%, TBI-TSA (1 mg/kg) 86%, TBI-LEV (54 mg/kg) 50%, TBI-LEV (150 mg/kg) 40% (p < 0.05 vs. TBI-vehicle), and TBI-LEV (150 mg/kg) combined with TSA (1 mg/kg) 30% (p < 0.05). Cumulative seizure duration was reduced in the following order: TBI-vehicle 727 ± 688 s, TBI-TSA 898 ± 937 s, TBI-LEV (54 mg/kg) 358 ± 715 s, TBI-LEV (150 mg/kg) 42 ± 64 (p < 0.05 vs. TBI-vehicle), and TBI-LEV (150 mg/kg) combined with TSA (1 mg/kg) 109 ± 282 s (p < 0.05). This first preclinical intervention study on post-TBI acute seizures shows that a combination therapy with the tissue recovery enhancer TSA and LEV was safe but exhibited no clear benefit over LEV monotherapy on antiseizure efficacy. A longer follow-up is needed to confirm the possible beneficial effects of LEV monotherapy and combination therapy with TSA on chronic post-TBI structural and functional outcomes, including epileptogenesis.

New-onset refractory status epilepticus (NORSE) in paediatric patients: causes, characteristics and outcomes

Background

New-onset refractory status epilepticus (NORSE) refers to patients without a previous history of seizures who have refractory status epilepticus for at least 72 hours without an identified aetiology. Despite the severe neurological sequelae of NORSE, little is known about this condition in paediatric patients.

Objective

To describe the profile of paediatric patients with NORSE, the profile of seizures, possible causes attributed to this condition, treatments offered to patients and the outcomes at discharge from the paediatric intensive care unit (PICU).

Methods

This retrospective, multicentre, descriptive study (case series) was conducted in the PICUs of three tertiary hospitals. We reviewed the medical records of all patients aged 0–16 years admitted to the participating PICUs between December 2013 and December 2017 with refractory status epilepticus, without a previous history of seizures or neurological disease.

Results

Fifteen patients (2.4%) had NORSE. The median age of patients was 62.3 (IQR 26.2–75.4) months. All patients experienced prodromes before progressing to refractory status epilepticus. Twelve patients (80%) had fever up to 24 hours before seizures. NORSE was classified as cryptogenic in 66% of patients. Twelve patients were treated with complementary therapies, in addition to anticonvulsants. There was no standardisation in the treatment of patients. The overall mortality rate was 20%.

Conclusions

NORSE is associated with high morbidity and mortality, without an identified aetiology in most cases and with a wide range of proposed therapies.

[Application of low-dose esmolamine in general anesthesia in pediatric surgeries]

OBJECTIVE

To explore the effect of continuous low-dose infusion of esmolamine on intraoperative dosage of opioids and awakening quality in general anesthesia in pediatric surgeries.

METHODS

A total of 100 children (6-8 years of age) undergoing pediatric surgery under general anesthesia were randomized equally into observation group and control group.In the observation group, the children received an intravenous injection of 0.1mg/kg esmolamine 10 min before induction of general anesthesia, followed by intravenous infusion of esmolamine at 2 μg•kg-1•min-1 until the end of the operation; those in the control group were infused with the same volume of normal saline instead of esmolamine in the same manner.The dosage of remifentanil during operation, recovery time of spontaneous breathing, recovery time of consciousness and extubation time were recorded in all the cases.The VAS score at 15, 30 and 60 min after extubation were assessed, and intravenous injection of naborphine 0.3 mg/kg was given for a VAS score ≥4;the total dosage of naborphine and adverse events were recorded for all the patients.

RESULTS

The total dose of remifentanil was significantly lower in the observation group than in the control group, but the spontaneous respiratory recovery time, consciousness recovery time and extubation time did not differ significantly between the two groups.The VAS scores at 15, 30 and 60 min after extubation were all better in the observation group than in the control group; the total intraoperative dose of naborphine was significantly lower in the observation group.

CONCLUSION

Continuous infusion of low-dose esmolamine during pediatric surgery can effectively lower intraoperative dosage of opioids and reduce pain during recovery without affecting the quality of awakening.

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.

Intramuscular Midazolam for treatment of Status Epilepticus

INTRODUCTION

Status epilepticus (SE) is a common neurological and medical emergency. It has high mortality and morbidity rates, which typically correlate with seizure semiology and duration; therefore, prompt and proper pharmacological intervention is paramount. In a pre-hospital setting, establishing venous access can be difficult, so other routes of drug administration should be considered.

AREAS COVERED

The paper summarizes the data from the literature and provides an evaluation of the efficacy and safety of intramuscular midazolam (IM MDZ) as it pertains to the management of acute seizures and SE.

EXPERT OPINION

The cascade of events involved in the genesis and sustenance of seizures, if not promptly stopped, lead to the perpetuation of the condition and may contribute to the refractoriness of pharmacological treatment. Hence, non-venous routes for drug administration were developed to allow untrained personnel to rapidly stop seizures. Among benzodiazepines (BDZs), IM MDZ is at least as effective and safe as other intravenously administered BDZs. Moreover, thanks to IM MDZ's favorable pharmacodynamic and pharmacokinetic profile, it is a promising alternative to other non-venous drugs such as intranasal-MDZ, buccal-MDZ, and rectal-diazepam in the pre-hospital management of SE cases with motor features.

Ketamine-dexmedetomidine combination and controlled mild hypothermia for the treatment of long-lasting and super-refractory status epilepticus in 3 dogs suffering from idiopathic epilepsy

OBJECTIVE

To describe the use of a ketamine-dexmedetomidine combination and mild hypothermia for the treatment of status epilepticus in 3 dogs that did not respond to GABAergic medication.

CASE SERIES SUMMARY

Three dogs, each with a diagnosis of idiopathic epilepsy, were presented to the emergency department in a state of status epilepticus. The dogs were treated unsuccessfully with benzodiazepine as a first-line therapy that was followed by IV propofol anesthesia maintained for at least 12 hours. When general anesthesia was discontinued, seizures reoccurred. All 3 dogs then received a bolus of ketamine (1 mg/kg, IV) over a period of 5 minutes that was followed by a bolus of dexmedetomidine (3 μg/kg, IV) over the same time period and then followed by a continuous infusion for 12 hours of ketamine at a constant rate of 1 mg/kg/h and dexmedetomidine at a variable rate of 3-7 μg/kg/h. Body temperature was maintained between 36.7 and 37.7°C at a state of mild hypothermia throughout treatment. The dogs recovered uneventfully over 48 hours after treatment was discontinued with no evidence of seizures. No notable alterations in physiological parameters were observed during the drug infusions. All dogs were discharged following examinations that showed normal neurological function.

NEW OR UNIQUE INFORMATION PROVIDED

This case series highlights the potential benefits of a ketamine-dexmedetomidine infusion combined with mild hypothermia for the treatment of status epilepticus refractory to GABAergic therapy in dogs suffering from idiopathic epilepsy. After the dogs were weaned from the ketamine-dexmedetomidine infusion, all dogs experienced complete recovery. Thus, this case series introduces a novel approach to treat this intense condition.

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.

Can Generic Intravenous Levetiracetam Be Used for Acute Repetitive Convulsive Seizure or Status Epilepticus? A Randomized Controlled Trial

INTRODUCTION

Intravenous levetiracetam (IV LEV) is approved for treatment status epilepticus (SE). However, the drug's high cost must be considered when deciding on a treatment strategy. This study aimed to compare the efficacy of brand-name and generic IV LEV for acute repetitive convulsive seizure (ARCS) or SE.

METHODS

Forty patients aged 18 years or older who had been diagnosed with SE or ARCS were included in this double-blind study. Patients were randomly assigned at a 1:1 ratio (via computer-generated code) to receive either brand-name or generic IV LEV. The primary outcomes were seizure control and the number of seizure exacerbations during the 24 h after drug administration, while the secondary outcomes were electroencephalographic (EEG) findings, serious adverse events, and clinical outcome at hospital discharge.

RESULTS

Forty patients were randomly assigned administration with either brand-name IV LEV (10 SE and 10 ARCS patients) or generic IV LEV; 7 SE and 13 ARCS patients). There was no significant difference in patients' baseline characteristics. The seizure control rate was 75% in the brand-name IV LEV group and 65% in the generic IV LEV group (p value: 0.490). Five (25%) patients in the brand-name IV LEV group, and six (30%) patients in the generic IV LEV group developed seizure exacerbations within 24 h after drug administration (p value 0.723). There were no reports of drug-related adverse events. Two of the patients taking brand-name IV LEV and one taking the generic IV LEV died (p value > 0.999).

CONCLUSION

Treatment with the generic IV LEV had comparable outcomes with brand-name IV LEV. The generic IV LEV may be an alternative medication for the treatment of SE and ARCS to reduce treatment costs.

TRIAL REGISTRATION

TCTR20190513001.

FUNDING

Great Eastern Drug Company.

Factors associated with 30-day readmission for patients hospitalized for seizures

Background

We sought to determine the cumulative incidence of readmissions after a seizure-related hospitalization and identify risk factors and readmission diagnoses.

Methods

We performed a retrospective cohort study of adult patients hospitalized with a primary discharge diagnosis of seizure (International Classification of Diseases, Ninth Edition, Clinical Modification codes 345.xx and 780.3x) using the State Inpatient Databases across 11 states from 2009 to 2012. Hospital and community characteristics were obtained from the American Hospital Association and Robert Wood Johnson Foundation. We performed logistic regressions to explore effects of patient, hospital, and community factors on readmissions within 30 days of discharge.

Results

Of 98,712 patients, 13,929 (14%) were readmitted within 30 days. Reasons for readmission included epilepsy/convulsions (30% of readmitted patients), mood disorders (5%), schizophrenia (4%), and septicemia (4%). The strongest predictors of readmission were diagnoses of CNS tumor (odds ratio [OR] 2.1, 95% confidence interval [CI] 1.9-2.4) or psychosis (OR 1.8, 95% CI 1.7-1.8), urgent index admission (OR 2.0, 95% CI 1.8-2.2), transfer to nonacute facilities (OR 1.7, 95% CI 1.6-1.8), long length of stay (OR 1.7, 95% CI 1.6-1.8), and for-profit hospitals (OR 1.7, 95% CI 1.6-1.8). Our main model's c-statistic was 0.66. Predictors of readmission for status epilepticus included index admission for status epilepticus (OR 3.5, 95% CI 2.6-4.7), low hospital epilepsy volume (OR 0.4, 95% CI 0.3-0.7), and rural hospitals (OR 4.8, 95% CI 2.1-10.9).

Conclusion

Readmission is common after hospitalization for seizures. Prevention strategies should focus on recurrent seizures, the most common readmission diagnosis. Many factors were associated with readmission, although readmissions remain challenging to predict.

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

Objective:

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

Method:

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

Results:

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

Conclusion:

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

[Diagnosis and treatment of status epilepticus in the intensive care unit]

Both convulsive and nonconvulsive status epilepticus are associated with a high risk of morbidity and mortality. To limit brain damage, emergency investigation of etiology and treatment must be done synchronously. This review presents the general rules for treatment. The steps of pharmacologic escalation with benzodiazepines, antiepileptics, and anesthetics are discussed together with their advantages and disadvantages.

Altered hippocampal interneuron activity precedes ictal onset

Although failure of GABAergic inhibition is a commonly hypothesized mechanism underlying seizure disorders, the series of events that precipitate a rapid shift from healthy to ictal activity remain unclear. Furthermore, the diversity of inhibitory interneuron populations poses a challenge for understanding local circuit interactions during seizure initiation. Using a combined optogenetic and electrophysiological approach, we examined the activity of identified mouse hippocampal interneuron classes during chemoconvulsant seizure induction in vivo. Surprisingly, synaptic inhibition from parvalbumin- (PV) and somatostatin-expressing (SST) interneurons remained intact throughout the preictal period and early ictal phase. However, these two sources of inhibition exhibited cell-type-specific differences in their preictal firing patterns and sensitivity to input. Our findings suggest that the onset of ictal activity is not associated with loss of firing by these interneurons or a failure of synaptic inhibition but is instead linked with disruptions of the respective roles these interneurons play in the hippocampal circuit.

Intranasal Therapy to Stop Status Epilepticus in Prehospital Settings

Status epilepticus (SE) is a medical emergency characterized by uncontrolled, prolonged seizures with rapid and widespread neuronal damage. Patients that suffer from longer episodes of SE are more likely to have poorer clinical outcomes and a higher cost of healthcare. Understanding novel molecular mechanisms that regulate inhibitory and excitatory neurotransmission that initiate SE and the necessary medical infrastructure to stop SE could help identify targets for early intervention. Intranasal administration of benzodiazepines may shorten the time between initiation and cessation of seizures when compared to other routes of administration. Current pharmaceutical administration guidelines are appropriate for sporadic incidences of SE, but exploring other approaches is necessary to prepare for situations involving multiple patients outside of a hospital, such as a massive chemical weapons attack. Intranasal drug delivery helps to circumvent the blood–brain barrier and offers a noninvasive way to quickly administer drugs in settings that require an immediate response, such as nerve agent exposure. In addition, examining the intranasal delivery of new drugs, such as nanotherapeutics, may lead to more effective, noninvasive, scalable, and portable methods of treating SE.

S(+)-ketamine : Current trends in emergency and intensive care medicine

S(+)-ketamine, the pure dextrorotatory enantiomer of ketamine has been available for clinical use in analgesia and anesthesia for more than 25 years. The main effects are mediated by non-competitive inhibition of the N-methyl-D-aspartate (NMDA) receptor but S(+)-ketamine also interacts with opioid receptors, monoamine receptors, adenosine receptors and other purinergic receptors. Effects on α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, metabotropic glutamate receptors (mGluR) and L‑type calcium chanels have also been described. S(+)-ketamine stimulates the sympathetic nerve system, making it an ideal drug for analgosedation or induction of anesthesia in instable patients. In addition, the neuroprotective properties, bronchodilatory, antihyperalgesic or antiepileptic effects provide interesting therapeutic options. In this article we discuss the numerous effects of S(+)-ketamine under pharmacological and clinical aspects especially for typical indications in emergency medicine as well as intensive care.

Development and Validation of an LC-MS/MS Method and Comparison with a GC-MS Method to Measure Phenytoin in Human Brain Dialysate, Blood, and Saliva

Phenytoin (PHT) is one of the most often used critical dose drugs, where insufficient or excessive dosing can have severe consequences such as seizures or toxicity. Thus, the monitoring and precise measuring of PHT concentrations in patients is crucial. This study develops and validates an LC-MS/MS method for the measurement of phenytoin concentrations in different body compartments (i.e., human brain dialysate, blood, and saliva) and compares it with a formerly developed GC-MS method that measures PHT in the same biological matrices. The two methods are evaluated and compared based on their analytical performance, appropriateness to analyze human biological samples, including corresponding extraction and cleanup procedures, and their validation according to ISO 17025/FDA Guidance for Industry. The LC-MS/MS method showed a higher performance compared with the GC-MS method. The LC-MS/MS was more sensitive, needed a smaller sample volume (25 µL) and less chemicals, was less time consuming (cleaning up, sample preparation, and analysis), and resulted in a better LOD (<1 ng/mL)/LOQ (10 ng/mL). The calibration curve of the LC-MS/MS method (10-2000 ng/mL) showed linearity over a larger range with correlation coefficients r2 > 0.995 for all tested matrices (blood, saliva, and dialysate). For larger sample numbers as in pharmacokinetic/pharmacodynamic studies and for bedside as well as routine analyses, the LC-MS/MS method offers significant advantages over the GC-MS method.

Protective Effects of Cannabidiol against Seizures and Neuronal Death in a Rat Model of Mesial Temporal Lobe Epilepsy

The present study reports the behavioral, electrophysiological, and neuropathological effects of cannabidiol (CBD), a major non-psychotropic constituent of Cannabis sativa, in the intrahippocampal pilocarpine-induced status epilepticus (SE) rat model. CBD was administered before pilocarpine-induced SE (group SE+CBDp) or before and after SE (group SE+CBDt), and compared to rats submitted only to SE (SE group), CBD, or vehicle (VH group). Groups were evaluated during SE (behavioral and electrophysiological analysis), as well as at days one and three post-SE (exploratory activity, electrophysiological analysis, neuron density, and neuron degeneration). Compared to SE group, SE+CBD groups (SE+CBDp and SE+CBDt) had increased SE latency, diminished SE severity, increased contralateral afterdischarge latency and decreased relative powers in delta (0.5–4 Hz) and theta (4–10 Hz) bands. Only SE+CBDp had increased vertical exploratory activity 1-day post SE and decreased contralateral relative power in delta 3 days after SE, when compared to SE group. SE+CBD groups also showed decreased neurodegeneration in the hilus and CA3, and higher neuron density in granule cell layer, hilus, CA3, and CA1, when compared to SE group. Our findings demonstrate anticonvulsant and neuroprotective effects of CBD preventive treatment in the intrahippocampal pilocarpine epilepsy model, either as single or multiple administrations, reinforcing the potential role of CBD in the treatment of epileptic disorders.

[Not Available]

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.