Status epilepticus: pathophysiology, epidemiology, and outcomes

Anticonvulsive evaluation and histopathological survey of thalidomide synthetic analogs on lithium-pilocarpine-induced status epilepticus in rats

Background and purpose:

Status epilepticus is a severe neurological disorder that can be life-threatening. Thalidomide and its analogs have shown promising results to confront pentylenetetrazole-induced seizures. This study aimed to evaluate the potential effects of three synthesized thalidomide derivatives on lithium-pilocarpine-induced status epilepticus.

Experimental approach:

To induce status epilepticus, rats received lithium chloride (127 mg/kg, i.p.) and pilocarpine HCl (60 mg/kg, i.p.) 20 h after lithium chloride injection. Thirty min before pilocarpine HCl administration, rats received hyoscine N-butyl bromide (1 mg/kg, i.p.) and concurrently one of the test compounds (5B, 5C, and 5D), diazepam, thalidomide, or vehicle (4% DMSO) to evaluate their anti-epileptic effects. Epileptic seizures scores were assessed through the Racine scale. Twenty-four h after injection of pilocarpine, brain samples were extracted for further histopathological evaluation.

Findings/Results:

Results revealed that among tested compounds (5B, 5C, and 5D), only compound 5C (1 mg/kg) exhibited excellent anti-epileptic activity comparable to diazepam (10 mg/kg). Compound 5D (100 mg/kg) only demonstrated comparable anti-epileptic activity to thalidomide (1 mg/kg). Compound 5B did not have any anti-epileptic activity even at the dose of 100 mg/kg. The histopathological survey showed that compound 5C has more neuroprotective effects than diazepam and thalidomide in the cortex of the brain. In the cornu ammonis 1 region, thalidomide had higher protective properties and in the cornu ammonis 3 and dentate gyrus areas, diazepam had higher efficacy to prevent necrosis.

Conclusion and implications:

Compound 5C is a good candidate for further studies regarding its potency, compared to thalidomide and diazepam.

Oro-mucosal midazolam maleate: Use and effectiveness in adults with epilepsy in the UK

BACKGROUND

Oro-mucosal midazolam maleate (OMM) with suitable training to family and carers is being increasingly recognized as the treatment of choice to mitigate the development of status epilepticus in non-hospital community settings. There are no studies to describe the use, effectiveness, and suitable dosing of OMM in adults with epilepsy in community settings.

PURPOSE

To describe the use, effectiveness, and dosing of OMM in the emergency treatment of epileptic seizures in community settings.

METHODS

A retrospective observational study (2016-17) design was used with participant recruitment from four UK NHS secondary care outpatient clinics providing epilepsy management. Study sample was of adult people with epilepsy (PWE) having had a recent seizure requiring OMM. Data on patient demographics, patient care plans, details of a recent seizure requiring emergency medication, and dose of OMM were collected from medical records.

RESULTS

Study data from 146 PWE were included. The mean age of PWE was 41.0 years (SD 15.2) and mean weight was 64.8Kg (SD 18.2). Fifty-three percent of PWE were recorded as having intellectual disability. The most frequently used concomitant medications were lamotrigine (43%). The majority of seizures occurred at people's homes (n = 92, 63%). OMM was most often administered by family/professional care-givers (n = 75, 48.4%). Generalized (tonic/clonic) seizures were recorded in most people (n = 106, 72.6%). The most common initial dose of OMM was 10 mg (n = 124, 84.9%). The mean time to seizure cessation after administration of this initial dose was 5.5 minutes (SD = 4.5, Median 5.0, IQR 2.1-5.0). Only a minority of seizures led to ambulance callouts (n = 18, 12.3%) or hospital admissions (n = 13, 9%).

CONCLUSION

This is the first observational study describing the use and effectiveness of OMM in adults in community settings. Minimal hospital admissions were reported in this cohort and the treatment was effective in ending seizures in adults in community settings.

Role of epilepsy surgery in refractory status epilepticus in children

INTRODUCTION

Status epilepticus (SE) is one of the most common medical emergencies, requiring urgent treatment; nearly 30 % patients develop refractory SE. The role of epilepsy surgery (ES) for refractory SE however remains unclear with empirical evidence limited to single case reports and small case series. The aim of the present study was to determine the clinical presentation, imaging characteristics and outcome of children with refractory SE who underwent emergency ES for refractory SE.

MATERIAL AND METHOD

Patients who had SE, failed to respond to escalating medical treatment of SE with/ without pharmacological suppression therapy, and eventually underwent ES were included.

RESULTS

There were ten children, 7 boys and 3 girls (range 6 months to 14 years). The age of onset of epilepsy varied from day 2 of life to 12.8 years. The duration of SE prior to surgery was 2-6 days (mean 3.7 days). Four patients had hemimegalencephaly, 3 had focal cortical dysplasia, 2 had Rasmussen's encephalitis, and one had hemispheric porencephalic cyst. The time interval between onset of seizures and ES ranged from 2 months to 8 years (mean 3.1 year). Seven patients underwent hemispherotomy, resection of dysplasia in two and temporo-parieto-occipital disconnection in one. Nine had Engel I outcome and Engel IIIa in one, at follow up of 12-44 months (mean 31 months).

CONCLUSION

Emergency ES is an effective treatment option for termination of refractory SE in children with structural pathology, after failure of medical treatment. Patients with refractory SE with focal or hemispheric structural abnormality on MRI, and concordant semiology with/without concordant EEG can be surgical candidates with or without invasive monitoring.

Epidemiology and outcome of status epilepticus in children: a Scottish population cohort study

AIM

To describe the epidemiology and outcomes of convulsive status epilepticus (CSE) since the introduction of buccal midazolam and the change in International League Against Epilepsy definition of CSE to include seizures of at least 5 minutes.

METHOD

All children presenting to paediatric emergency departments with CSE (2011-2017) in Lothian, Scotland, were identified. Data, collated from electronic health records, included patient demographics, clinical characteristics, acute seizure management, and adverse outcomes (for example admission to intensive care).

RESULTS

Six hundred and sixty-five children were admitted with CSE who had 1228 seizure episodes (381 males, 284 females; median age 3y 8mo; age range 0-20y 11mo). CSE accounted for 0.38% (95% confidence interval 0.34-0.42) of annual attendances at emergency departments. Annual prevalence was 0.8 per 1000 children aged 0 to 14 years. Thirty-four per cent of children had recurrent CSE. Sixty-nine per cent of seizures lasted 5 to 29 minutes (median duration 10min). Buccal midazolam was given to 30% of children with CSE and had no effect on need for ventilatory support. Seventy per cent of children with CSE required hospital admission. Four per cent resulted in adverse outcome and there were only two deaths. Recurrent seizures, longer duration, and unprovoked seizures increased the odds of adverse outcome.

INTERPRETATION

Adverse outcomes have decreased and the use of buccal midazolam is promising. Identifying high-risk groups provides an opportunity for early intervention. These data form the basis for an extensive evaluation of acute seizure management and monitoring long-term outcomes. What this paper adds The annual prevalence of convulsive status epilepticus in Lothian, Scotland, was 0.8 per 1000 children. There was a decrease in case-fatality proportion from 3-9% to 0.2%. Use of buccal midazolam has increased, with no increase in adverse outcomes.

An Insight into the Current Understanding of Status Epilepticus: From Concept to Management

Status epilepticus (SE), a subset of epilepsy, represents a debilitating neurological disorder often associated with alarming mortality and morbidity numbers. Even though SE is one of the extensively researched topics with conspicuous data available in the literature, a scientific gap exists in understanding the heterogeneous facets of the disorder like occurrence, definition, classification, causes, molecular mechanisms, etc., thereby providing a defined management program. Cognizance of this heterogeneity and scientific limitation with its subsequent correlation to the recent advancements in medical and scientific domains would serve not only in bridging the gap but also in developing holistic and prompt management programs. Keeping this as an objective, an extensive literature survey was performed during this study, and key findings have been shared. The present study provides a semantic and perspective synopsis toward acknowledging the diversified nature of SE and its variants with respect to their definition, classification, etiology, diagnosis, and management.

Levetiracetam for convulsive status epilepticus in childhood: systematic review and meta-analysis

IMPORTANCE

Prolonged seizures are life-threatening emergencies associated with significant morbidity.

OBJECTIVE

To determine the efficacy and safety of levetiracetam in treating convulsive status epilepticus (CSE) in childhood.

DATA SOURCES AND STUDY SELECTIONS

PubMed, Embase, the Cochrane Central Register of Controlled Trials and Cumulative Index to Nursing and Allied Health Literature were searched from inception up to April 2020. Only randomised controlled trials (RCTs) that included children aged 1 month-18 years were assessed. Two reviewers performed data assessment and extraction.

DATA EXTRACTION AND SYNTHESIS

Ten studies out of the 20 637 citations identified were included.

MAIN OUTCOMES

Cessation of seizure activities, time to cessation of seizure activities, need for rapid sequence intubation (RSI), intensive care unit (ICU) admission, recurrence of seizures at 24 hours, adverse events and all-cause mortality.

RESULTS

We included 10 RCTs (n=1907). There was no significant difference in cessation of seizure activities when levetiracetam was compared with phenytoin (risk ratio (RR)=1.03, 95% CI 0.98 to 1.09), levetiracetam to fosphenytoin (RR=1.16, 95% CI 1.00 to 1.35) or levetiracetam to valproate (RR=1.10, 95% CI 0.94 to 1.27). No differences were found in relation to the timing of cessation of seizures for levetiracetam versus phenytoin (mean difference (MD)=-0.45, 95% CI -1.83 to 0.93), or levetiracetam versus fosphenytoin (MD=-0.70, 95% CI -4.26 to 2.86). There were no significant differences with regard to ICU admissions, adverse events, recurrence of seizure at 24 hours, RSI and all-cause mortality.

CONCLUSION

Levetiracetam is comparable to phenytoin, fosphenytoin and valproate as a second line treatment of paediatric CSE.

Treatment of Seizures in Children and Adults in the Emergency Medical System of the City of Zurich, Switzerland - Midazolam vs. Diazepam - A Retrospective Analysis

INTRODUCTION

Seizures count to critical situations emergency medical systems (EMS) are confronted with.

OBJECTIVES

Evaluation of a modified treatment algorithm (MTAS-EMS) using diazepam and midazolam due to a supply bottleneck of iv lorazepam in 2012.

METHODS

Retrospective study where data from patients treated for seizures by the EMS of the city of Zurich were analyzed. Effectiveness of the MTAS-EMS and i.v. diazepam in children and adults was compared with respect of cessation of seizure without recurrence over the period until arrival at the hospital. The chi-square and Fisher's exact test were used to compare categorical data. The Student's t-test and Mann Whitney test were used to compare numerical data. p-values < 0.05 are considered significant.

RESULTS

Of 584 documented missions, 165 treated patients (126 adults and 39 children) were included. 115 patients (80 adults and 35 children) were treated according the MTAS-EMS. Cessation of seizure was achieved in 85% of the adults and in 97% of the children, if all options of the MTAS-EMS were used. The first dose of nasal midazolam was more successful in children compared to adults (p = 0.012). In adults, the single dose of i.v. diazepam terminated the seizure in 98% (p = 0.001) compared to 57% for the single dose of iv and 64% for nasal midazolam.

CONCLUSIONS

The treatment success of the MTAS-EMS is high. However, in adults the single dose of i.v. diazepam is as successful as the completely used MTAS-EMS and seems to be superior to the single dose iv and nasal midazolam.

Course and Outcome of Children with Convulsive Status Epilepticus Admitted to a Pediatric Intensive Care Unit

Introduction The objective of this study was to describe the course and the outcomes of children with convulsive status epilepticus and to evaluate the differences between two groups of children with new-onset seizures and known seizure disorders. Methods This is a retrospective, single-center study. Children with convulsive status epilepticus admitted to our tertiary care pediatric intensive care unit were included in the study. Medical records were reviewed to obtain the demographic- and seizure-related variables. Results Among 139 children with status epilepticus, 69.7% (n = 99) had a known seizure disorder. Focal seizures were present in 23.9% of children, and 34.6% required intubation; there was an overall mortality rate of 1.2%. The children with new-onset seizures were younger and received electroencephalography (EEG) and neuroimaging more often compared to children with known seizure disorders (p < 0.05). However, an abnormal EEG was more common among children with known seizure disorders (p < 0.001). Conclusions Sub-therapeutic anti-epileptic drugs levels were common among children with known seizure disorders presenting with status epilepticus. Gender, race, insurance status, type of seizures, intubation requirement, lengths of stay, and mortality were not significantly different between the two groups.

Midazolam vs diazepam in prolonged seizures in children: A pharmacoeconomic approach

OBJECTIVE

A previous European cost-utility study reported that use of buccal midazolam in the community setting for the treatment of prolonged seizures (ie, seizures lasting ≥5 minutes) in children was associated with an overall €12 507 399 reduction in annual costs charged to the Italian national health service compared with rectal diazepam. We re-evaluated these findings by applying a more conservative approach.

METHODS

The Italian Delphi panel reconvened to apply a more conservative assessment of available reports. A decision-tree model was used, allowing for different treatment pathways depending on whether or not a caregiver administers treatment, an ambulance is required for transport of the child to hospital, and an inpatient stay is required. Direct medical costs were derived from Italian healthcare system data. Estimates of the annual number of prolonged tonic-clonic seizures expected in the country were based on studies which assessed seizure duration using video-EEG recordings and medical records.

RESULTS

Although drug acquisition costs were greater for buccal midazolam than for rectal diazepam, the acquisition cost difference was outweighed by larger cost savings resulting mostly from a reduction in hospital admissions. Assuming that 1.2% of tonic and/or clonic seizures occurring in children and adolescents over a 12-month period are prolonged, the annual nationwide reduction in costs from preferring buccal midazolam to rectal diazepam was estimated at €3 577 587.9.

CONCLUSIONS

In this more conservative revised analysis, the high cost of buccal midazolam is still counteracted by greater cost savings compared with rectal diazepam, but cost reduction was less than previously estimated.

Adult Status Epilepticus: A Review of the Prehospital and Emergency Department Management

Seizures are a common presentation in the prehospital and emergency department setting and status epilepticus represents an emergency neurologic condition. The classification and various types of seizures are numerous. The objectives of this narrative literature review focuses on adult patients with a presentation of status epilepticus in the prehospital and emergency department setting. In summary, benzodiazepines remain the primary first line therapeutic agent in the management of status epilepticus, however, there are new agents that may be appropriate for the management of status epilepticus as second- and third-line pharmacological agents.

Single Center Outcomes of Status Epilepticus at a Paediatric Intensive Care Unit

BACKGROUND

Status epilepticus (SE) is a frequent admission diagnosis to paediatric intensive care units (PICUs) and is associated with variable outcomes. We have audited our experience of patients presenting in SE at a Canadian PICU to determine unfavorable outcome variables.

METHODS

Charts of patients <18 years of age presenting in SE to a tertiary care PICU over a 10-year period were audited. Data were analyzed at three care-points: transport, the emergency department (ED) and the PICU. Patient outcome before PICU discharge was categorized as "favorable" for return to pre-status functioning level or "unfavorable" for new deficit/death. Student's t-test and the Kruskal-Wallis test were used for analysis of normal and skewed continuous variables, respectively, and either Chi-square test or Fisher's exact test for categorical variables.

RESULTS

189 patients (54% males) were identified with a median age of 1.9 years. Idiopathic SE had the highest incidence; infectious/vascular etiologies were associated with more unfavorable outcomes. Progression to refractory SE in the ED had a higher incidence of death (p<0.05). Patients with an unfavorable outcome had a higher incidence of apnea during transport (p=0.01), longer hospital stays (p<0.05), need for therapeutic coma (p=0.01), longer duration of therapeutic coma (p<0.05), need for mechanical ventilation (p<0.05), and recurrent or refractory seizures during inpatient stay (p<0.05). Multivariate analysis of unfavorable outcomes of patients in SE presenting to the PICU included renal failure, cerebral edema, apnea during transport, refractory seizures, and recurrent seizures.

CONCLUSIONS

Refractory seizures in children presenting with SE are associated with worsened outcomes in the PICU.

What is the easier and more reliable dose calculation for iv phenytoin in children at risk of developing convulsive status epilepticus, 18 mg/kg or 20 mg/kg?

Background

With the Convulsive Status Guidelines due for renewal, we wondered if a phenytoin dose of ‘20 mg/kg’ would be easier to calculate correctly and therefore safer than the current ‘18 mg/kg’. An educational exercise in dose calculation was therefore undertaken to assess ease of calculation.

Method

A standard question paper was prepared, comprising five clinical scenarios with children of varying ages and estimated body weights. Medical students, trainee doctors at registrar and senior house officer level, and consultant paediatricians were asked to complete the exercise, in private, by one of two medical students (SD, PS). Calculations were done with and without a calculator, for 18 mg/kg and for 20 mg/kg in randomised order. Speed and errors (greater than 10%) were determined. The data analysis was performed using SPSS version 18.

Results

All answered all 20 scenarios, giving a total of 300 answers per doctor/student group, and 300 answers per type of calculation. When comparing the 2 doses, the numbers of errors more than 10% were significantly less in 20 mg/kg dose (0.33%) as compared to the 18 mg/kg dose (9.3%) (p<0.0001). Speed off calculation was significantly decreased in 20 mg/kg dose when compared with 18 mg/kg dose, with (p<0.001) or without (p<0.0001) the calculator. Speed was more than halved and errors were much less frequent by using a calculator, for the 18 mg/kg dose but no difference with or without the calculator for 20 mg/kg dose.

Conclusion

We recommend that the future guidelines should suggest iv Phenytoin at 20 mg/kg rather than 18 mg/kg. This will make the calculation easier and reduce the risk of significant errors.

Cognitive outcome of status epilepticus in children

Epileptic encephalopathy encompasses conditions in which cognitive, motor, or sensory deficits result as a consequence of epileptic activity defining certain syndromes. It therefore represents a more severe subset of epilepsy, which can be generally characterized as frequent or severe seizures leading to cerebral dysfunction. This disturbance in cerebral functioning can in turn hinder, somewhat dramatically, cognitive development and further impact the future lives of patients. In this paper, we describe the cognitive consequences of status epilepticus in children and in adults in the context of plasticity theories. Recent studies maintain that consequences of SE may be severe cognitive sequelae, especially in early life. Since the residual consequences of SE in adulthood seem less detrimental and long-lasting, we argue that early life insults, such as those created by SE, during a rapid period of development and functional specialization, result in specific cognitive deficits dependent on the sensitive period at which SE occurred.

Epidemiology of Status Epilepticus Among Children in Qatar in 2008

AbstractBackground:Convulsive status epilepticus (CSE) in childhood is a medical emergency and its epidemiology should be studied separately from adult CSE; this study reviewed pediatric cases reported in Qatar in 2008.Methods:A retrospective study for a defined pediatric age group (30 days <  age <  15 years) with SE was carried out in Qatar for 12 months and included 25 patients.Results::Of the patients, 56% male, 44% female, 56% were younger than 2 years, and 52% had febrile status epilepticus, 76.9% of whom were boys. All who displayed prolonged seizure status (more than 45 min) had abnormal EEG and brain CT readings and required a prolonged stay in PICU; 20% had history of status epilepticus before.Conclusions::The incidence of SE in Qatar is similar to reports around the world, and the age-specific incidence pattern is similar as well. Febrile status epilepticus is the most important cause especially in boys. Symptomatic SE has a significantly longer duration with higher risk for recurrence than idiopathic SE.

Status Epilepticus in Children

Status epilepticus (SE) is a life-threatening emergency that requires prompt treatment, including basic neuroresuscitation principles (the ABCs), antiepileptic drugs to stop the seizure and identification of etiology. It results from an inability to normally abort an isolated seizure either due to ineffective inhibition, or due to abnormally persistent excessive excitation. Symptomatic SE is more common in younger children and the likely etiology depends on the age of the child. Treating the precipitating cause may prevent ongoing neurologic injury and facilitates seizure control. Benzodiapenes, phenytoin and phenobarbital form the mainstay of treatment. A systematic treatment regimen, planned in advance, is needed, including one for refractory status epilepticus (RSE). Patient education and home management of seizures is important to reduce the morbidity and mortality associated with SE.

Vascular endothelial growth factor attenuates status epilepticus-induced behavioral impairments in rats

Vascular endothelial growth factor (VEGF) is a vascular growth factor more recently recognized as a neurotrophic factor (for review, see Storkebaum E, Lambrechts D, Carmeliet P. BioEssays 2004;26:943-54). We previously reported that endogenous VEGF protein is dramatically upregulated after pilocarpine-induced status epilepticus in the rat, and that intra-hippocampal infusions of recombinant human VEGF significantly protected against the loss of hippocampal CA1 neurons in this model (Nicoletti JN, Shah SK, McCloskey DP, et al. Neuroscience 2008;151:232-41). We hypothesized that we would see a preservation of cognitive and emotional functioning with VEGF treatment accompanying the neuroprotection previously observed in this paradigm. Using the Morris water maze to evaluate learning and memory, and the light-dark task to assess anxiety, we found a selective profile of preservation. Specifically, VEGF completely preserved normal anxiety functioning and partially but significantly protected learning and memory after status epilepticus. To determine whether the ability of VEGF to attenuate behavioral deficits was accompanied by sustained preservation of hippocampal neurons, we stereologically estimated CA1 pyramidal neuron densities 4 weeks after status epilepticus. At this time point, we found no significant difference in neuronal densities between VEGF- and control-treated status epilepticus animals, suggesting that VEGF could have protected hippocampal functioning independent of its neuroprotective effect.

Efficacy and usability of buccal midazolam in controlling acute prolonged convulsive seizures in children

A Prolonged convulsive seizure is the most common neurological medical emergency with poor outcome. An ideal anticonvulsant should be easy-to-use, effective, and safe, and it should also have a long-lasting effect. Benzodiazepines, give via the intravenous or rectal route have generally been used as first-line drugs. In small children, IV access can be difficult and time consuming. Midazolam is a potent anticonvulsant and is rapidly absorbed from the rectal, nasal, and buccal mucosa. Our aim was to evaluate the efficacy and usability of buccal midazolam in controlling seizures in children with acute prolonged seizures, by comparing it with rectal diazepam. Ninety-eight patients were enrolled, with 49 patients in each treatment group. In the buccal midazolam group, 42 (88%) patients were controlled in less than 4 min of drug administration, and all of the patients were controlled within 5 min of drug administration. In the rectal diazepam group, 24 (49%) patients were controlled in less than 4 min and 40 (82%) patients were controlled within 5 min of drug administration. The time for drug administration and drug effect was significantly less with buccal midazolam than with rectal diazepam (p value<0.001). In the buccal midazolam group, 46 (94%) parents were satisfied with their child's treatment and route of drug administration while in the rectal diazepam group, 7 (14%) parents were satisfied. Buccal midazolam was significantly more acceptable than rectal diazepam (p value<0.001). In conclusion, buccal midazolam may be as effective as rectal diazepam but more convenient to use in the controlling acute prolonged seizures in children, especially in situations in which there is a difficulty in gaining IV access, for example, in infants.

Convulsive status epilepticus in children

Introduction. Convulsive status epilepticus is the most urgent neurological medical emergency in children. Generalized convulsive status epilepticus is the most common and life-threatening type of status epilepticus. It is not a syndrome in the same sense as febrile convulsions, benign rolandic epilepsy, and infantile polymorphic epilepsy. These latter disorders have a tight age frame, seizure semiology, and a reasonably predictable outcome. Episodes of convulsive status epilepticus can occur in each: occasionally in symptomatic and febrile convulsions, and Lennox Gastaut syndrome, rarely in benign rolandic epilepsy, and West syndrome. Etiology of convulsive status epilepticus. Status epilepticus has many causes, which vary depending on the age and patient population. Convulsive status epileptucus continues to be associated with significant neurological morbidity and mortality, with different hazards and outcome. Although the outcome is dependent on etiology, it is known that appropriate early management may reduce mortality and some of the morbidity associated with convulsive status epilepticus. Discussion. Status epilepticus is a disorder in which the mechanisms attempting at terminating the seizure fail. Continued convulsive activity in convulsive status epilepticus results in decompensation of all organs and systems, thus being life threatening. Seizure activity in convulsive status epilepticus is associated with neuronal damage. The aim should be to halt this activity urgently, using, ideally, a 100% effective drug, administered quickly, without compromising the consciousness level or producing other negative effects on cardiovascular, respiratory function or other unexpected effects.

Intravenous midazolam in convulsive status epilepticus in children with pharmacoresistant epilepsy

Although the efficacy of midazolam in refractory status epilepticus and as a first-line agent in children with established status epilepticus has been reported, differences in starting doses, continuation method, timing of efficacy assessment, and discontinuation pose limitations in deriving a specific protocol for midazolam use. An audit of clinical experience with a protocol of midazolam as first-line agent for impending status epilepticus (defined as a continuous, generalized, convulsive seizure lasting >5 minutes) in 76 episodes of unprovoked convulsive status epilepticus in children 1-15 years old with treatment-refractory epilepsy demonstrated that: (1) repeated bolus midazolam 0.1mg/kg (every 5 minutes, maximum 5) controlled 91% of events; (2) three bolus doses controlled 89% of the episodes, with minimal chance of response beyond that; (3) treating impending status resulted in lower doses (mean 0.17 mg/kg) than reported and infrequent utilization of additional anticonvulsants (9%); and (4) adverse events were infrequent (respiratory depression 13%, assisted ventilation 3%).

Emergency management of pediatric convulsive status epilepticus: a multicenter study of 542 patients

OBJECTIVE

To perform a multicenter study examining the presentations and emergency management of children with convulsive status epilepticus (CSE) to sites within the Paediatric Research in Emergency Departments International Collaborative.

METHODS

Retrospective review of children presenting to emergency departments (EDs) with convulsive seizures of at least 10 minutes' duration. Eight sites within the Paediatric Research in Emergency Departments International Collaborative network in Australia and New Zealand participated. Patients were identified through a search of ED electronic records for the period January 2000 to December 2004.

RESULTS

Data were obtained from 542 eligible episodes of CSE. Demographics and seizure history were similar across all sites. One third of children with CSE presented with their first seizure. A preexisting diagnosis that predisposed to seizures was present in 59%. Median duration of seizures before hospitalization was 45 minutes, and median duration of treatment in ED before termination was 30 minutes. Prehospital duration did not seem to influence the timing of key ED interventions such as the administration of second-line anticonvulsants or progression to rapid sequence induction (RSI) of anesthesia and intubation. Convulsive status epilepticus was terminated after first-line treatment in 42%, second-line treatment in 35%, and RSI in 22%. One third of the patients had persistent seizure activity beyond 40 minutes of ED treatment. Marked variation in the use of RSI for refractory seizures was observed between sites.

CONCLUSIONS

Convulsive status epilepticus is an important neurological emergency, with many children experiencing prolonged seizures in both the prehospital and hospital phases. Persistent seizure activity beyond 40 minutes contrasts with current published guidelines. There is a need to adopt a widely accepted approach to the management of children who fail to respond to standard anticonvulsant therapy.

The community use of rescue medication for prolonged epileptic seizures in children

OBJECTIVES

The objectives for this study were to determine the prevalence of use, safety and efficacy of different preparations of rescue medication used for prolonged seizures in children in the community and to use the information gained to inform good practice within the network.

METHODS

For all children in the EPIC area who had been prescribed epilepsy rescue medication for use in the community a questionnaire was completed by the clinician for each child relating to rescue medication prescribed, the epilepsy syndrome and seizure type. A questionnaire was also completed by the carers about their experience of the use of rescue medication in their child.

RESULTS

A total of 203 paediatrician questionnaires were returned and 190 parent/carer questionnaires were returned. Buccal Midazolam was the most popular rescue medication (Buccal Midazolam 110, Rectal Diazepam 85, Paraldehyde 8). Over 80% of the children had a community care plan in place. 90% of carers recalled receiving instruction/training in the administration of rescue medication. The majority (73%) of carers perceived Buccal Midazolam and Rectal Diazepam to be effective in preventing hospital admission.

CONCLUSION

Buccal Midazolam in its propriety form is the rescue medication most commonly prescribed by EPIC epilepsy paediatricians. It was felt by families to be the safest (least side effects reported) and the most effective (most likely to terminate seizures) of the rescue medications. Children with severe epilepsy benefit from the use of rescue medications and the number of hospital admissions for prolonged seizures is reduced.

An alternative perspective on the management of status epilepticus

The definition of status epilepticus (SE) has been reduced from 30 minutes to 5 minutes and this article questions if treatment should not be offered before reaching that window. After provision of first aid, benzodiazepines (BDZ) are the initial form of intervention, with either nasal or buccal midazolam being favored for nonprofessionals. Proper patient supervision, including admission to an intensive care unit for more difficult patients, is endorsed, and the need to warn nonprofessionals of the potential risk of respiratory depression is imperative. The article criticizes the use of phenytoin as the antiepileptic medication (AEM) with which to load patients, as it is no longer a first-line AEM, and argues in favor of using a first-line AEM such as valproate or carbamazepine, or preferably the AEM that previously proved efficacious in a patient with known epilepsy who was noncompliant. Alternative routes of administration of AEMs are discussed, and the use of blood level monitoring, as an adjunct to management, to protect against further episodes of SE, is supported. Touched on in this article are the use of some of the newer AEMs in the management of SE and exploration of treatment strategies that acknowledge that treatment must also include patient education that incorporates techniques to enhance compliance.

Outcome of convulsive status epilepticus: a review

The outcome of CSE in childhood depends mainly upon the cause but length of seizure may also be important

Aetiology, course and outcome of children admitted to paediatric intensive care with convulsive status epilepticus: a retrospective 5-year review

A retrospective case note study of the aetiology and course of children in convulsive status epilepticus (CSE) admitted to a large paediatric intensive care unit (PICU) was undertaken between January 1999 and April 2004. Status epilepticus was defined as a prolonged (>30 min) tonic-clonic seizure irrespective of whether the seizure had stopped prior to admission to PICU. During this period, 137 (74 male) children aged 1 month to 15 years were admitted to PICU with 147 episodes of status epilepticus. Forty-seven of the 137 children (34%) were admitted following a prolonged febrile seizure. Thirty-eight of the 137 children (28%) had a remote symptomatic cause for the CSE, 24 (18%) were admitted for an acute symptomatic cause and 15 (11%) were admitted with an acute exacerbation of a pre-existing idiopathic/cryptogenic epilepsy. Six children had a progressive encephalopathy and no cause was identified in the remaining 7 of the 137 children (5%). Forty-nine (36%) of the 137 children had pre-existing epilepsy. The mean duration of CSE was 44 min. Forty-nine (36%) children admitted to PICU who had received a benzodiazepine with either phenobarbital or phenytoin, required further treatment to terminate the presenting episode of CSE. Forty-two of these 49 were treated with thiopentone anaesthesia and the remaining 7 with a continuous infusion of midazolam, successfully terminating status in all. No child died. Of the 70 children considered to be previously neurologically and developmentally normal prior to admission, only 1 child demonstrated a new gross neurological abnormality at the time of latest follow-up. Seven patients (5%) developed new or de novo epilepsy.

When benzodiazepines fail: how effective is second line therapy for status epilepticus in children?

OBJECTIVES

To define the characteristics and management of children presenting to the ED of a major tertiary paediatric hospital with convulsive status epilepticus (CSE). To determine the timing and efficacy of therapeutic interventions in this group and to identify factors that influence the effectiveness of treatment.

METHOD

A retrospective audit of all children who presented to an ED of a tertiary paediatric hospital in CSE over a 3 year period.

RESULTS

Thirty-seven cases were identified. Prehospital treatment had been administered in 51%. Uncomplicated seizure control was achieved in 30% with the combination of first and second line therapy. Rapid sequence induction (RSI) of anaesthesia was required in 70% for the control of ongoing seizure activity (21 cases) or to support severe respiratory depression (five cases). This requirement for RSI was increased to 85% in those with seizure duration in excess of 30 min and 89% of those who received prehospital treatment. Of those who required RSI, 35% were treated for periods in excess of 60 min before this intervention was performed.

CONCLUSIONS

Standard second line anticonvulsant treatment was relatively ineffective in terminating seizures in children who presented in CSE not responsive to benzodiazepines. Failure to respond to prehospital treatment and prolonged seizure duration at presentation both predict poor therapeutic response. Third line treatment with RSI of anaesthesia is often delayed while waiting for second line treatment to work.

Outcome of paediatric convulsive status epilepticus: a systematic review

We did a systematic review on the outcome of paediatric convulsive status epilepticus (CSE) and investigated the role of biological and non-biological variables in reported outcomes. The methodological quality of the 63 studies that met our inclusion criteria was assessed. Study design, type of study, and length of follow-up influenced the outcome. The studies with highest methodological quality are associated with better outcome: short-term mortality between 2.7% and 5.2% and morbidity other than epilepsy less than 15%. The incidence of subsequent epilepsy is not increased after cryptogenic CSE. Causal factor is the main determinant of outcome and the effect of age or duration is difficult to separate from the underlying cause. The risk of sequelae in unprovoked and febrile CSE is low. There is some evidence that CSE, especially febrile CSE, might cause hippocampal injury, although its role in the development of mesial temporal sclerosis is unknown.

[Markers of poor prognosis in convulsive status epilepticus]

OBJECTIVE

To characterize the variables that might be associated with mortality and the development of neurological deficits in children with convulsive status epilepticus.

PATIENTS AND METHODS

Children older than 1 month and younger than 15 years who were admitted to the pediatric intensive care unit of a university hospital between 2001 and 2004 were reviewed. Epidemiologic and clinical factors that might be related to neurological outcome at discharge from the unit were analyzed.

RESULTS

Forty-one patients (median age 24 months) were included. A total of 48.3% developed refractory convulsive status epilepticus. Six patients died (mortality 14.6%) during their intensive care unit stay and neurologic worsening was observed in 8.6% of survivors (adverse outcome in 22%). Symptomatic epilepsy was present in all patients who died and in 88.9% of those who recovered with severe neurologic sequelae. Uni- and multivariate analysis showed that adverse outcome was related to symptomatic origin and refractory convulsive status epilepticus (p < 0.05).

CONCLUSIONS

Mortality and morbidity is high in childhood convulsive status epilepticus. Refractory convulsive status and symptomatic origin were markers of poor outcome. Children who did not have symptomatic epilepsy had a favorable outcome.

Safety and efficacy of buccal midazolam versus rectal diazepam for emergency treatment of seizures in children: a randomised controlled trial

BACKGROUND

Rectal diazepam and buccal midazolam are used for emergency treatment of acute febrile and afebrile (epileptic) seizures in children. We aimed to compare the safety and efficacy of these drugs.

METHODS

A multicentre, randomised controlled trial was undertaken to compare buccal midazolam with rectal diazepam for emergency-room treatment of children aged 6 months and older presenting to hospital with active seizures and without intravenous access. The dose varied according to age from 2.5 to 10 mg. The primary endpoint was therapeutic success: cessation of seizures within 10 min and for at least 1 hour, without respiratory depression requiring intervention. Analysis was per protocol.

FINDINGS

Consent was obtained for 219 separate episodes involving 177 patients, who had a median age of 3 years (IQR 1-5) at initial episode. Therapeutic success was 56% (61 of 109) for buccal midazolam and 27% (30 of 110) for rectal diazepam (percentage difference 29%, 95% CI 16-41). Analysing only initial episodes revealed a similar result. The rate of respiratory depression did not differ between groups. When centre, age, known diagnosis of epilepsy, use of antiepileptic drugs, prior treatment, and length of seizure before treatment were adjusted for with logistic regression, buccal midazolam was more effective than rectal diazepam.

INTERPRETATION

Buccal midazolam was more effective than rectal diazepam for children presenting to hospital with acute seizures and was not associated with an increased incidence of respiratory depression.

Fosphenytoin for the treatment of status epilepticus: an evidence-based assessment of its clinical and economic outcomes

INTRODUCTION

Status epilepticus (SE) is a life-threatening condition requiring prompt treatment in the emergency department to control seizures and limit potential neurologic damage. Fosphenytoin is a water-soluble prodrug of phenytoin (an established treatment option for SE) that has been developed to overcome the often severe venous adverse events that can occur following the intravenous administration of phenytoin.

AIMS

The objective of this article is to review the evidence for the use of fosphenytoin in the treatment of SE.

EVIDENCE REVIEW

Fosphenytoin can be infused more rapidly than phenytoin and there is evidence that therapeutic drug levels are achieved at least at a similar rate. Although few studies have been conducted in SE patients, there is evidence that fosphenytoin is at least as effective as phenytoin in terms of response and control of SE. There is also moderate evidence that there are fewer vascular adverse events following intravenous fosphenytoin compared with phenytoin administration when both drugs are infused at the recommended dosage and rate. Evidence from pharmacoeconomic studies indicates that a reduction in the incidence of adverse events and their subsequent management are critical factors for cost-effectiveness with fosphenytoin.

CLINICAL VALUE

In conclusion, fosphenytoin is a valuable treatment option for the rapid treatment of SE; the risk of venous adverse events is lower than with phenytoin when administered at the recommended rate.

Efficacy of Topiramate in Children with Refractory Status Epilepticus

PURPOSE

Status epilepticus (SE) is a life-threatening medical condition associated with significant morbidity and mortality that requires urgent medical intervention. Although several agents are available to treat SE, they occasionally fail to abort seizure activity. Topiramate (TPM) was anecdotally reported to be effective in adult patients with refractory SE. In this study, we evaluated the efficacy of TPM administered to children with this condition.

METHODS

We retrospectively reviewed the pediatric SE database at the University of Michigan Medical Center and identified three children with refractory SE who were treated with TPM. Those children failed to respond to treatment with benzodiazepines, phenytoin, phenobarbital, midazolam, or pentobarbital. Additional treatment with TPM was administered by nasogastric tube. All patients were continuously monitored by 21-channel digital EEG machines, and the diagnosis of SE was made by a board-certified neurophysiologist.

RESULTS

The ages of the three children were 4.5 months, 34 months, and 11 years. TPM was initiated at 2 mg/kg/day in two children and at 3 mg/kg/day in the third. The status was terminated in all three children within 24 h of maintenance therapy with TPM at 5-6 mg/kg/day.

CONCLUSIONS

These results support the potential efficacy of TPM for children with refractory SE. Larger prospective series are needed to confirm those results.

Controlling seizures in the prehospital setting: diazepam or midazolam?

OBJECTIVE

To determine which is the most effective and safe treatment for controlling seizures in children out-of-hospital: diazepam or midazolam.

METHODS

A retrospective review of the medical records of children presenting to the Emergency Department of the Children's Hospital at Westmead (CHW-ED) with seizures requiring treatment in the field by paramedics was carried out over a 4-year period (April 1996 to March 2000). In New South Wales, children with seizures in the prehospital setting received 0.5 mg/kg per rectum (p.r.) or 0.1 mg/kg i.v. diazepam until March 1998 and from March 1997 onwards they received 0.15 mg/kg i.m. or 0.1 mg/kg i.v. midazolam. The main outcome measured was cessation of seizure in the prehospital setting. Secondary outcomes were time taken to initiate treatment and the frequency of cardiorespiratory compromise.

RESULTS

Over the 4-year period, 2566 children presented to CHW-ED with a seizure; 107 children were eligible for entry into the present study. Of these 107 patients, 62 received diazepam and 45 received midazolam. Thirty-one (50.0%) in the diazepam group and 15 (33.3%) in the midazolam group were febrile seizures. Both groups were similar in terms of demographics and seizure type. A comparison of diazepam with midazolam showed that both drugs were effective in stopping seizures within 5 min of drug administration (37.1% cf. 51.1%). Fewer patients in the midazolam group suffered apnoea (20.0% cf. 29.0%; P < 0.05).

CONCLUSION

Midazolam controls seizures as effectively as diazepam in the prehospital setting. Furthermore, midazolam potentially reduces respiratory depression and time to treatment.

The treatment of convulsive status epilepticus in children. The Status Epilepticus Working Party, Members of the Status Epilepticus Working Party

There is currently little agreement between hospital protocols when treating convulsive status epilepticus in children, and a working party has been set up to produce a national evidence based guideline for treating this condition. This four step guideline is presented in this paper. Its effectiveness will be highlighted and its use audited in a number of centres.

Status epilepticus: new concepts

Generalized convulsive status epilepticus is a neurological emergency characterized by abnormally prolonged seizures. This review emphasizes recent developments that bear on our understanding of the pathophysiology and management of status epilepticus. Topics include GABAA receptor modulation during prolonged seizures, the role of genetics in susceptibility to status epilepticus, neuron-specific enolas, the Veterans Administration Cooperative Study Group trial comparison of various drug regimens, utility of the electroencephalogram in patient monitoring, emerging drug therapies and patient management in out-of-hospital settings.