A comparison of four treatments for generalized convulsive status epilepticus. Veterans Affairs Status Epilepticus Cooperative Study Group

Status epilepticus: what's new for the intensivist

PURPOSE OF REVIEW

Status epilepticus (SE) is a common neurologic emergency affecting about 36.1/100 000 person-years that frequently requires intensive care unit (ICU) admission. There have been advances in our understanding of epidemiology, pathophysiology, and EEG monitoring of SE, and there have been large-scale treatment trials, discussed in this review.

RECENT FINDINGS

Recent changes in the definitions of SE have helped guide management protocols and we have much better predictors of outcome. Observational studies have confirmed the efficacy of benzodiazepines and large treatment trials indicate that all routinely used second line treatments (i.e., levetiracetam, valproate and fosphenytoin) are equally effective. Better understanding of the pathophysiology has indicated that nonanti-seizure medications aimed at underlying pathological processes should perhaps be considered in the treatment of SE; already immunosuppressant treatments are being more widely used in particular for new onset refractory status epilepticus (NORSE) and Febrile infection-related epilepsy syndrome (FIRES) that sometimes revealed autoimmune or paraneoplastic encephalitis. Growing evidence for ICU EEG monitoring and major advances in automated analysis of the EEG could help intensivist to assess the control of electrographic seizures.

SUMMARY

Research into the morbi-mortality of SE has highlighted the potential devastating effects of this condition, emphasizing the need for rapid and aggressive treatment, with particular attention to cardiorespiratory and neurological complications. Although we now have a good evidence-base for the initial status epilepticus management, the best treatments for the later stages are still unclear and clinical trials of potentially disease-modifying therapies are long overdue.

Small-molecule caspase-1 inhibitor CZL80 terminates refractory status epilepticus via inhibition of glutamatergic transmission

Status epilepticus (SE), a serious and often life-threatening medical emergency, is characterized by abnormally prolonged seizures. It is not effectively managed by present first-line anti-seizure medications and could readily develop into drug resistance without timely treatment. In this study, we highlight the therapeutic potential of CZL80, a small molecule that inhibits caspase-1, in SE termination and its related mechanisms. We found that delayed treatment of diazepam (0.5 h) easily induces resistance in kainic acid (KA)-induced SE. CZL80 dose-dependently terminated diazepam-resistant SE, extending the therapeutic time window to 3 h following SE, and also protected against neuronal damage. Interestingly, the effect of CZL80 on SE termination was model-dependent, as evidenced by ineffectiveness in the pilocarpine-induced SE. Further, we found that CZL80 did not terminate KA-induced SE in Caspase-1-/- mice but partially terminated SE in IL1R1-/- mice, suggesting the SE termination effect of CZL80 was dependent on the caspase-1, but not entirely through the downstream IL-1β pathway. Furthermore, in vivo calcium fiber photometry revealed that CZL80 completely reversed the neuroinflammation-augmented glutamatergic transmission in SE. Together, our results demonstrate that caspase-1 inhibitor CZL80 terminates diazepam-resistant SE by blocking glutamatergic transmission. This may be of great therapeutic significance for the clinical treatment of refractory SE.

Status epilepticus: Is there a Stage 1 plus?

In status epilepticus (SE), "time is brain." Currently, first-line therapy consists of benzodiazepines (BDZs) and SE is classified by the response to treatment; stage 2 or established SE is defined as "BDZ-resistant SE." Nonetheless, this classification does not always work, especially in the case of prolonged convulsive SE, where many molecular changes occur and γ-aminobutyric acid signaling becomes excitatory. Under these circumstances, BDZ therapy might not be optimal, and might be possibly detrimental, if given alone; as the duration of SE increases, so too does BDZ resistance. Murine models of SE showed how these cases might benefit more from synergistic combined therapy from the start. The definition of Stage 1 plus is suggested, as a stage requiring combined therapy from the start, which includes prolonged SE with seizure activity going on for >10 min, the time that marks the disruption of receptor homeostasis, with increased internalization. This specific stage might require a synergistic approach from the start, with a combination of first- and second-line treatment.

Estimate of Patients With Missed Seizures Because of Delay in Conventional EEG

PURPOSE

There is frequent delay between ordering and placement of conventional EEG. Here we estimate how many patients had seizures during this delay.

METHODS

Two hundred fifty consecutive adult patients who underwent conventional EEG monitoring at the University of Wisconsin Hospital were retrospectively chart reviewed for demographics, time of EEG order, clinical and other EEG-related information. Patients were stratified by use of anti-seizure medications before EEG and into low-risk, medium-risk, and high-risk groups based on 2HELPS2B score (0, 1, or >1). Monte Carlo simulations (500 trials) were performed to estimate seizures during delay.

RESULTS

The median delay from EEG order to performing EEG was 2.00 hours (range of 0.5-8.00 hours) in the total cohort. For EEGs ordered after-hours, it was 2.00 hours (range 0.5-8.00 hours), and during business hours, it was 2.00 hours (range 0.5-6.00 hours). The place of EEG, intensive care unit, emergency department, and general floor, did not show significant difference (P = 0.84). Anti-seizure medication did not affect time to first seizure in the low-risk (P = 0.37), medium-risk (P = 0.44), or high-risk (P = 0.12) groups. The estimated % of patients who had a seizure in the delay period for low-risk group (2HELPS2B = 0) was 0.8%, for the medium-risk group (2HELPS2B = 1) was 10.3%, and for the high-risk group (2HELPS2B > 1) was 17.6%, and overall risk was 7.2%.

CONCLUSIONS

The University of Wisconsin Hospital with 24-hour in-house EEG technologists has a median delay of 2 hours from order to start of EEG, shorter than published reports from other centers. Nonetheless, seizures were likely missed in about 7.2% of patients.

Efficacy of a combined anti-seizure treatment against cholinergic established status epilepticus following a sarin nerve agent insult in rats

The development of refractory status epilepticus (SE) following sarin intoxication presents a therapeutic challenge. Here, we evaluated the efficacy of delayed combined double or triple treatment in reducing abnormal epileptiform seizure activity (ESA) and the ensuing long-term neuronal insult. SE was induced in rats by exposure to 1.2 LD50 sarin followed by treatment with atropine and TMB4 (TA) 1 min later. Double treatment with ketamine and midazolam or triple treatment with ketamine, midazolam and levetiracetam was administered 30 min post-exposure, and the results were compared to those of single treatment with midazolam alone or triple treatment with ketamine, midazolam, and valproate, which was previously shown to ameliorate this neurological insult. Toxicity and electrocorticogram activity were monitored during the first week, and behavioral evaluations were performed 2 weeks post-exposure, followed by biochemical and immunohistopathological analyses. Both double and triple treatment reduced mortality and enhanced weight recovery compared to TA-only treatment. Triple treatment and, to a lesser extent, double treatment significantly ameliorated the ESA duration. Compared to the TA-only or the TA+ midazolam treatment, both double and triple treatment reduced the sarin-induced increase in the neuroinflammatory marker PGE2 and the brain damage marker TSPO and decreased gliosis, astrocytosis and neuronal damage. Finally, both double and triple treatment prevented a change in behavior, as measured in the open field test. No significant difference was observed between the efficacies of the two triple treatments, and both triple combinations completely prevented brain injury (no differences from the naïve rats). Delayed double and, to a greater extent, triple treatment may serve as an efficacious delayed therapy, preventing brain insult propagation following sarin-induced refractory SE.

Nonconvulsive Status Epilepticus: Clinical Findings, EEG Features, and Prognosis in a Developing Country, Mexico

PURPOSE

There is a lack of clinical and epidemiological knowledge about nonconvulsive status epilepticus (NCSE) in developing countries including Mexico, which has the highest prevalence of epilepsy in the Americas. Our aim was to describe the clinical findings, EEG features, and outcomes of NCSE in a tertiary center in Mexico.

METHODS

We conducted a retrospective case series study (2010-2020) including patients (≥15 years old) with NCSE according to the modified Salzburg NCSE criteria 2015 with at least 6 months of follow-up. We extracted the clinical data (age, sex, history of epilepsy, antiseizure medications, clinical manifestations, triggers, and etiology), EEG patterns of NCSE, and outcome. Descriptive statistics and multinomial logistic regression were used.

RESULTS

One hundred thirty-four patients were analyzed; 74 (54.8%) women, the total mean age was 39.5 (15-85) years, and 71% had a history of epilepsy. Altered state of consciousness was found in 82% (including 27.7% in coma). A generalized NCSE pattern was the most common (32.1%). The NCSE etiology was mainly idiopathic (56%), and previous uncontrolled epilepsy was the trigger in 48% of patients. The clinical outcome was remission with clinical improvement in 54.5%. Multinomial logistic regression showed that the patient's age (P = 0.04), absence of comorbidities (P = 0.04), history of perinatal hypoxia (P = 0.04), absence of clinical manifestations (P = 0.01), and coma (P = 0.03) were negatively correlated with the outcome and only the absence of generalized slowing in the EEG (P = 0.001) had a significant positive effect on the prognosis.

CONCLUSIONS

Age, history of perinatal hypoxia, coma, and focal ictal EEG pattern influence negatively the prognosis of NCSE.

Ivermectin Exerts Anticonvulsant Effects Against Status Epilepticus Induced by Lithium-Pilocarpine in Rats via GABAA Receptor and Neuroinflammation Modulation: Possible Interaction of Opioidergic Pathways and KATP Channel with Nitrergic System

Status epilepticus (SE) is a critical medical emergency marked by persistent or rapidly repeating seizures, posing a threat to life. Using the lithium-pilocarpine-induced SE model, we decide to evaluate the anti-seizure effects of ivermectin as a positive allosteric modulator of GABAA receptor and the underlying mechanisms involved. Lithium chloride was injected intraperitoneally at a dose of 127 mg/kg, followed by the administration of pilocarpine at a dose of 60 mg/kg after a 20-h interval in order to induce SE. Subsequently, the rats received varying amounts of ivermectin (0.3, 1, 3, 5, and 10 mg/kg, i.p.) 30 min before the onset of SE. To study the underlying molecular mechanisms, we had pharmacological interventions of diazepam (1 mg/kg), glibenclamide and nicorandil as ATP-sensitive potassium channel blocker and opener (both 1 mg/kg, i.p.), naltrexone and morphine, as opioid receptor antagonist and agonist (1 mg/kg and 0.5 mg/kg, i.p., respectively). In addition, three nitric oxide inhibitors, namely, L-NAME (10 mg/kg, i.p.), 7-NI (30 mg/kg, i.p.), and aminoguanidine (100 mg/kg, i.p.), were administered to the rats in the experiment. Finally, we use ELISA and western blotting, respectively, to examine the amounts of pro-inflammatory cytokines (TNF-α and IL-1β), nitrite, and GABAA receptors in the rat hippocampal tissue. The study found that ivermectin, at doses of 3, 5, and 10 mg/kg, exerts anti-seizure effects and decrease Racine's scale SE score. Interestingly glibenclamide and naltrexone reduced the anti-seizure effects of ivermectin, and from other hand diazepam, nicorandil, morphine, L-NAME, 7-NI, and aminoguanidine, enhance the effects when co-administrated with subeffective dose of ivermectin. Additionally, the study found that ivermectin decreased the elevated levels of TNF-α and IL-1β following SE, while increased the reduced expression of GABAA receptors. Overall, these findings suggest that ivermectin has anti-seizure effects in a SE seizure which may be mediated by the modulation of GABAergic, opioidergic, and nitrergic pathways and KATP channels.

Established and emerging GABAA receptor pharmacotherapy for epilepsy

Drugs that modulate the GABAA receptor are widely used in clinical practice for both the long-term management of epilepsy and emergency seizure control. In addition to older medications that have well-defined roles for the treatment of epilepsy, recent discoveries into the structure and function of the GABAA receptor have led to the development of newer compounds designed to maximise therapeutic benefit whilst minimising adverse effects, and whose position within the epilepsy pharmacologic armamentarium is still emerging. Drugs that modulate the GABAA receptor will remain a cornerstone of epilepsy management for the foreseeable future and, in this article, we provide an overview of the mechanisms and clinical efficacy of both established and emerging pharmacotherapies.

Staged treatment response in status epilepticus: Lessons from the SENSE registry

OBJECTIVES

Although in epilepsy patients the likelihood of becoming seizure-free decreases substantially with each unsuccessful treatment, to our knowledge this has been poorly investigated in status epilepticus (SE). We aimed to evaluate the proportion of SE cessation and functional outcome after successive treatment steps.

METHODS

We conducted a post hoc analysis of a prospective, observational, multicenter cohort (Sustained Effort Network for treatment of Status Epilepticus [SENSE]), in which 1049 incident adult SE episodes were prospectively recorded at nine European centers. We analyzed 996 SE episodes without coma induction before the third treatment step. Rates of SE cessation, mortality (in ongoing SE or after SE control), and favorable functional outcome (assessed with modified Rankin scale) were evaluated after each step.

RESULTS

SE was treated successfully in 838 patients (84.1%), 147 (14.8%) had a fatal outcome (36% of them died while still in SE), and 11 patients were transferred to palliative care while still in SE. Patients were treated with a median of three treatment steps (range 1-13), with 540 (54.2%) receiving more than two steps (refractory SE [RSE]) and 95 (9.5%) more than five steps. SE was controlled after the first two steps in 45%, with an additional 21% treated after the third, and 14% after the fourth step. Likelihood of SE cessation (p < 0.001), survival (p = 0.003), and reaching good functional outcome (p < 0.001) decreased significantly between the first two treatment lines and the third, especially in patients not experiencing generalized convulsive SE, but remained relatively stable afterwards.

SIGNIFICANCE

The significant worsening of SE prognosis after the second step clinically supports the concept of RSE. However, and differing from findings in human epilepsy, RSE remains treatable in about one third of patients, even after several failed treatment steps. Clinical judgment remains essential to determine the aggressiveness and duration of SE treatment, and to avoid premature treatment cessation in patients with SE.

Management of status epilepticus in pregnancy: a clinician survey

BACKGROUND

Status epilepticus in pregnancy (SEP) is rare and life-threatening for both mother and fetus. There are well-established guidelines for the management of women with epilepsy during pregnancy; however, there is little evidence guiding the management of SEP, leading to uncertainty among treating physicians. Therefore, this survey aims to investigate the real-world practices of physicians treating SEP to explore management approaches for improvements in care.

METHODS

An anonymous, electronic survey was created and distributed to neurointensivists and neurologists between September and December 2021.

RESULTS

One hundred physicians initiated the survey and 95 completed it in full: 87 (87%, 87/100) identified neurology as their primary specialty, 31 had subspecialty training in neurocritical care, and 48 had subspecialty training in epilepsy and/or clinical neurophysiology. Over half of the survey respondents (67%, 67/100) reported having participated in the management of SEP, with 48.9% (49/98) having done so in the past year. Most survey respondents (73%, 73/100) reported that their management approach to SEP is different than that of non-pregnant patients. Survey respondents were more likely to involve epilepsy consultants when treating SEP (58.5%, 58/99) and the vast majority involved Obstetrics/Maternal Fetal Medicine consultants (90.8%, 89/98). Survey respondents showed a clear preference for levetiracetam (89.7%, 87/97) in the treatment of benzodiazepine refractory status epilepticus followed by lacosamide (61%, 60/98) if an additional second line agent was needed. Valproate and phenobarbital were unlikely to be used. There was less agreement for the management of refractory and super-refractory SEP.

CONCLUSIONS

Levetiracetam is the most frequently used anti-seizure medication (ASM) for benzodiazepine-refractory SEP. Survey participants tended to manage SEP differently than in non-pregnant patients including greater involvement of interdisciplinary teams as well as avoidance of ASMs associated with known teratogenicity.

Comparison of induction agents for rapid sequence intubation in refractory status epilepticus: A single-center retrospective analysis

Endotracheal intubation, frequently required during management of refractory status epilepticus (RSE), can be facilitated by anesthetic medications; however, their effectiveness for RSE control is unknown. We performed a single-center retrospective review of patients admitted to a neurocritical care unit (NCCU) who underwent in-hospital intubation during RSE management. Patients intubated with propofol, ketamine, or benzodiazepines, termed anti-seizure induction (ASI), were compared to patients who received etomidate induction (EI). The primary endpoint was clinical or electrographic seizures within 12 h post-intubation. We estimated the association of ASI on post-intubation seizure using logistic regression. A sub-group of patients undergoing electroencephalography during intubation was identified to evaluate the immediate effect of ASI on RSE. We screened 697 patients admitted to the NCCU for RSE and identified 148 intubated in-hospital (n = 90 ASI, n = 58 EI). There was no difference in post-intubation seizure (26 % (n = 23) ASI, 29 % (n = 17) EI) in the cohort, however, there was increased RSE resolution with ASI in 24 patients with electrographic RSE during intubation (ASI: 61 % (n = 11/18) vs EI: 0 % (n = 0/6), p =.016). While anti-seizure induction did not appear to affect post-intubation seizure occurrence overall, a sub-group of patients undergoing electroencephalography during intubation had a higher incidence of seizure cessation, suggesting potential benefit in an enriched population.

Sustained effort network for treatment of status epilepticus/European academy of neurology registry on adult refractory status epilepticus (SENSE-II/AROUSE)

BACKGROUND

Status Epilepticus (SE) is a common neurological emergency associated with a high rate of functional decline and mortality. Large randomized trials have addressed the early phases of treatment for convulsive SE. However, evidence regarding third-line anesthetic treatment and the treatment of nonconvulsive status epilepticus (NCSE) is scarce. One trial addressing management of refractory SE with deep general anesthesia was terminated early due to insufficient recruitment. Multicenter prospective registries, including the Sustained Effort Network for treatment of Status Epilepticus (SENSE), have shed some light on these questions, but many answers are still lacking, such as the influence exerted by distinct EEG patterns in NCSE on the outcome. We therefore initiated a new prospective multicenter observational registry to collect clinical and EEG data that combined may further help in clinical decision-making and defining SE.

METHODS

Sustained effort network for treatment of status epilepticus/European Academy of Neurology Registry on refractory Status Epilepticus (SENSE-II/AROUSE) is a prospective, multicenter registry for patients treated for SE. The primary objectives are to document patient and SE characteristics, treatment modalities, EEG, neuroimaging data, and outcome of consecutive adults admitted for SE treatment in each of the participating centers and to identify factors associated with outcome and refractoriness. To reach sufficient statistical power for multivariate analysis, a cohort size of 3000 patients is targeted.

DISCUSSION

The data collected for the registry will provide both valuable EEG data and information about specific treatment steps in different patient groups with SE. Eventually, the data will support clinical decision-making and may further guide the planning of clinical trials. Finally, it could help to redefine NCSE and its management.

TRIAL REGISTRATION

NCT number: NCT05839418.

Status epilepticus in the ICU

Status epilepticus (SE) is a common medical emergency associated with significant morbidity and mortality. Management that follows published guidelines is best suited to improve outcomes, with the most severe cases frequently being managed in the intensive care unit (ICU). Diagnosis of convulsive SE can be made without electroencephalography (EEG), but EEG is required to reliably diagnose nonconvulsive SE. Rapidly narrowing down underlying causes for SE is crucial, as this may guide additional management steps. Causes may range from underlying epilepsy to acute brain injuries such as trauma, cardiac arrest, stroke, and infections. Initial management consists of rapid administration of benzodiazepines and one of the following non-sedating intravenous antiseizure medications (ASM): (fos-)phenytoin, levetiracetam, or valproate; other ASM are increasingly used, such as lacosamide or brivaracetam. SE that continues despite these medications is called refractory, and most commonly treated with continuous infusions of midazolam or propofol. Alternatives include further non-sedating ASM and non-pharmacologic approaches. SE that reemerges after weaning or continues despite management with propofol or midazolam is labeled super-refractory SE. At this step, management may include non-sedating or sedating compounds including ketamine and barbiturates. Continuous video EEG is necessary for the management of refractory and super-refractory SE, as these are almost always nonconvulsive. If possible, management of the underlying cause of seizures is crucial particularly for patients with autoimmune encephalitis. Short-term mortality ranges from 10 to 15% after SE and is primarily related to increasing age, underlying etiology, and medical comorbidities. Refractoriness of treatment is clearly related to outcome with mortality rising from 10% in responsive cases, to 25% in refractory, and nearly 40% in super-refractory SE.

The initial treatment in convulsive status epilepticus in China: A multi-center observational study

OBJECTIVE

To investigate the initial treatment of patients with convulsive status epilepticus (CSE) in a resource-limited region of China, and to discuss the difference of in-hospital outcomes and economic costs between those with guideline-recommended initial treatment and those without.

METHODS

In this retrospective study, we screened adult patients discharged with the diagnosis of CSE in four centers in west China. Individuals with different exposure to the initial drug were divided into benzodiazepine (BDZ) and non-BDZ group for outcome comparison. The primary outcomes were seizure control, and the ratio of patients who developed refractory SE. The secondary outcomes included in-hospital mortality, the modified Rankin Scale (mRS) score at discharge, in-hospital respiratory support rate, length, and cost of the stay.

RESULTS

Three-hundred and thirteen patients (127, 40.6% were women) with CSE were included. The median age was 43 (range 16-92). There were 152 (48.6%) patients initially treated with BDZ. Among the 36 who received midazolam as initial treatment, twenty-six received an insufficient dose. The other 116 (76.3%) patients in the BDZ group chose diazepam as initial treatment. Fifteen of them (12.9%) were treated underdose. In the non-BDZ group (161, 51.4%), antiseizure medications (ASMs) and/or coma-induced drugs were used as initial treatment. Among those initially administrated ASMs, intramuscular phenobarbital (38,37.6%) and valproate (46, 52.3%) were most frequently seen. There was a significant difference in the time latency to initial treatment and etiology between BDZ and non-BDZ group. The non-BDZ group reported a higher cessation rate after initial treatment compared to the BDZ group (P = 0.012). No significant difference in other primary and secondary outcomes.

SIGNIFICANCE

Non-adherence and underdosing of the initial treatment of SE were common in China. However, the non-BDZ group showed a better seizure control rate. The effect came from early aggressive medication, that is, the combination of ASMs and anesthesia. Non-BDZ group was not inferior to BDZs in terms of seizure control, the occurrence of in-hospital death, and poor outcome at discharge. More robust evidence is needed in developing settings when choosing the initial treatment.

Implications of starting antiepileptic treatment prior to electroencephalography in first epileptic seizures

INTRODUCTION

This study aimed to determine whether the administration of antiepileptic drugs (AED) alters the likelihood of detecting epileptiform abnormalities in electroencephalographies (EEG) performed early after a first epileptic seizure.

METHODS

We performed a retrospective, observational study including patients with a first seizure attended at our centre's emergency department between July 2014 and November 2019. We collected clinical data, as well as technical data on the acquisition and interpretation of the EEG performed within the first 72 hours after the seizure, and the factors related with seizure recurrence.

RESULTS

We recruited 155 patients with a mean (SD) age of 48.6 (22.5) years; 61.3% were men. Regarding seizure type, 51% presented tonic-clonic seizures of unknown onset and 12% presented focal to bilateral tonic-clonic seizures. Thirty-nine patients (25.2%) received AED treatment before the EEG was performed: 33 received a non-benzodiazepine AED and 6 received a benzodiazepine. Epileptiform abnormalities were observed in 29.7% of patients. Previous administration of AEDs was not significantly associated with the probability of detecting interictal epileptiform abnormalities (P = .25) or with the risk of recurrence within 6 months (P = .63).

CONCLUSIONS

Administration of AEDs before an early EEG following a first seizure does not decrease the likelihood of detecting epileptiform abnormalities. These findings suggest that starting AED treatment immediately in patients with a high risk of early recurrence does not imply a reduction in the diagnostic accuracy of the test.

Further advances in epilepsy

In 2017, one of us reviewed advances in epilepsy (Manford in J Neurol 264:1811-1824, 2017). The current paper brings that review up to date and gives a slight change in emphasis. Once again, the story is of evolution rather than revolution. In recognition that most of our current medications act on neurotransmitters or ion channels, and not on the underlying changes in connectivity and pathways, they have been renamed as antiseizure (ASM) medications rather than antiepileptic drugs. Cenobamate is the one newly licensed medication for broader use in focal epilepsy but there have been a number of developments for specific disorders. We review new players and look forward to new developments in the light of evolving underlying science. We look at teratogenicity; old villains and new concerns in which clinicians play a vital role in explaining and balancing the risks. Medical treatment of status epilepticus, long without evidence, has benefitted from high-quality trials to inform practice; like buses, several arriving at once. Surgical treatment continues to be refined with improvements in the pre-surgical evaluation of patients, especially with new imaging techniques. Alternatives including stereotactic radiotherapy have received further focus and targets for palliative stimulation techniques have grown in number. Individuals' autonomy and quality of life continue to be the subject of research with refinement of what clinicians can do to help persons with epilepsy (PWE) achieve control. This includes seizure management but extends to broader considerations of human empowerment, needs and desires, which may be aided by emerging technologies such as seizure detection devices. The role of specialist nurses in improving that quality has been reinforced by specific endorsement from the International League against Epilepsy (ILAE).

EEG criteria for diagnosing nonconvulsive status epilepticus in comatose - An unsolved puzzle: A narrative review

Introduction

Nonconvulsive status epilepticus (NCSE) is an important and often unrecognized cause of impaired awareness especially in critically ill patients, which can easily be missed. Electroencephalography (EEG) findings in clinically suspected cases are the mainstay of diagnosis.

Review summary

The EEG diagnostic criteria for NCSE have evolved over the past three decades. Furthermore, recent advancements in EEG technologies such as continuous EEG monitoring, and emergency department EEG, along with development of different diagnostic criteria, have increased the detection rate for NCSE in suspected cases. However, treating physicians should have a higher index of clinical suspicion and a lower threshold for recommending this valuable investigation. The introduction of different diagnostic criteria has made it easier for electroencephalographers to report NCSE; nevertheless, diagnosis is not always straightforward. This narrative review aimed to define and discuss the available literature on different EEG diagnostic criteria for NCSE.

Conclusion

There is a need for further prospective research to strengthen the diagnostic accuracy of the available diagnostic criteria, the modified Salzburg Consensus Criteria for NCSE (mSCNC) and updated American Clinical Neurophysiology Society (ACNS) 21 criteria, to verify their accuracy to detect NCSE in comatose patients.

Early and established status epilepticus: The impact of timing of intervention, treatment escalation and dosing on outcome

OBJECTIVE

We investigated the management and outcome of early and established status epilepticus including timing, dosing and selection of benzodiazepines along with the timing and efficacy of second line treatments.

METHODS

Retrospective single tertiary centre observational cohort study to identify all cases of SE between January 2019 and February 2022.

RESULTS

252 cases were identified. Seizures terminated spontaneously in 136 (54%) cases. 116 (46%) were given benzodiazepines, of which 29 (25%) were given at least one benzodiazepine by family/carers, and 72 (62.1%) received benzodiazepines by ambulance services. Benzodiazepines terminated seizures in 83 (71.6%) cases. The commonest benzodiazepine used was buccal midazolam (35.5%). Median time to first benzodiazepine was 14.5 (6-27) minutes. There was a positive correlation between time to first benzodiazepine and time to seizure cessation, progression to second- and third-line treatment, and respiratory complications (p<0.05). 73 (62.9%) cases received a correct benzodiazepine dose. Benzodiazepine underdosing was associated with longer seizure duration (p<0.05). 33 (28.4%) cases progressed to second-line treatment where mean time to treatment was 59.4 min (±32.3 min). The commonest second-line treatment was Levetiracetam (53.8%), followed by Phenytoin (43.6%) with SE termination in 57.5% cases. 14 (12.1%) cases progressed to third-line treatment; mean time to treatment was 60.6 min (±22.24 min). Respiratory complications occurred in 17 (6.75%) cases; none due to benzodiazepines. There were two deaths in refractory SE.

CONCLUSION

Early administration of benzodiazepines and optimal dosing is associated with a higher rate of SE termination. Levetiracetam was the most commonly used second line treatment.

Nonconvulsive Status Epilepticus: A Review for Emergency Clinicians

BACKGROUND

Status epilepticus is associated with significant morbidity and mortality and is divided into convulsive status epilepticus and nonconvulsive status epilepticus (NCSE).

OBJECTIVE

This review provides a focused evaluation of NCSE for emergency clinicians.

DISCUSSION

NCSE is a form of status epilepticus presenting with prolonged seizure activity. This disease is underdiagnosed, as it presents with nonspecific signs and symptoms, most commonly change in mental status without overt convulsive motor activity. Causes include epilepsy, cerebral pathology or injury, any systemic insult such as infection, and drugs or toxins. Mortality is primarily related to the underlying condition. Patients most commonly present with altered mental status, but other signs and symptoms include abnormal ocular movements and automatisms such as lip smacking or subtle motor twitches in the face or extremities. The diagnosis is divided into electrographic and electroclinical, and although electroencephalogram (EEG) is recommended for definitive diagnosis, emergency clinicians should consider this disease in patients with prolonged postictal state after a seizure with no improvement in mental status, altered mental status with acute cerebral pathology (e.g., stroke, hypoxic brain injury), and unexplained altered mental status. Assessment includes laboratory evaluation and neuroimaging with EEG. Management includes treating life-threatening conditions, including compromise of the airway, hypoglycemia, hyponatremia, and hypo- or hyperthermia, followed by rapid cessation of the seizure activity with benzodiazepines and other antiseizure medications.

CONCLUSIONS

An understanding of the presentation and management of NCSE can assist emergency clinicians in the care of these patients.

Real-life evidence about the use of intravenous brivaracetam in urgent seizures: The BRIV-IV study

PURPOSE

Urgent seizures are a medical emergency for which new therapies are still needed. This study evaluated the use of intravenous brivaracetam (IV-BRV) in an emergency setting in clinical practice.

METHODS

BRIV-IV was a retrospective, multicenter, observational study. It included patients ≥18 years old who were diagnosed with urgent seizures (including status epilepticus (SE), acute repetitive seizures, and high-risk seizures) and who were treated with IV-BRV according to clinical practice in 14 hospital centers. Information was extracted from clinical charts and included in an electronic database. Primary effectiveness endpoints included the rate of IV-BRV responder patients, the rate of patients with a sustained response without seizure relapse in 12 h, and the time between IV-BRV administration and clinical response. Primary safety endpoints were comprised the percentage of patients with adverse events and those with adverse events leading to discontinuation.

RESULTS

A total of 156 patients were included in this study. The mean age was 57.7 ± 21.5 years old with a prior diagnosis of epilepsy for 57.1% of patients. The most frequent etiologies were brain tumor-related (18.1%) and vascular (11.2%) epilepsy. SE was diagnosed in 55.3% of patients. The median time from urgent seizure onset to IV treatment administration was 60.0 min (range: 15.0-360.0), and the median time from IV treatment to IV-BRV was 90.0 min (range: 30.0-2400.0). Regarding dosage, the mean bolus infusion was 163.0 ± 73.0 mg and the mean daily dosage was 195.0 ± 87.0 mg. A total of 77.6% of patients responded to IV-BRV (66.3% with SE vs. 91% other urgent seizures) with a median response time of 30.0 min (range: 10.0-60.0). A sustained response was achieved in 62.8% of patients. However, adverse events were reported in 14.7%, which were predominantly somnolence and fatigue, with 4.5% leading to discontinuation. Eighty-six percent of patients were discharged with oral brivaracetam.

CONCLUSION

IV-BRV in emergency settings was effective, and tolerability was good for most patients. However, a larger series is needed to confirm the outcomes.

Long-term follow-up of phenobarbital versus valproate for generalized convulsive status epilepticus in adults: A randomized clinical trial

OBJECTIVE

Intravenous phenobarbital is frequently offered to patients with generalized convulsive status epilepticus (GCSE) in China, but its long-term benefits are unclear. We aimed to evaluate the long-term effects of intravenous phenobarbital on adult patients with GCSE.

METHODS

This randomized clinical trial with a 12-month follow-up was performed in Xuanwu Hospital, Capital Medical University (Beijing, China) between February 2011 and December 2021. After the failure of intravenous diazepam treatment, adult patients with GCSE were randomized to receive either intravenous phenobarbital or valproate. Neurological outcome within 12-month was dichotomized as good (modified Rankin scale, mRS 0-2) or poor (mRS 3-6). Cognitive function was measured by mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA). Hamilton anxiety scale (HAMA) and Hamilton depression scale (HAMD) were tested for mood disorders.

RESULTS

We consecutively recruited 166 patients with GCSE. After excluding individuals with termination after intravenous diazepam (n = 61), and with other exclusion criteria (n = 7), 98 patients were included and 88.0% (66/75) of survivors achieved seizure freedom at 12-month. Forty-five patients (45.92%) had good outcomes at 3-month and 57 patients (58.16%) had good outcomes at 12-month. And 46.67% (35/75) of survivors showed mRS improvement at 12-month (phenobarbital group, n = 17 vs. valproate group, n = 18, P = 0.321). Despite there was no significant difference with respect to good outcomes at 3-month (54.0% vs. 37.5%, P = 0.101), the rate of good outcomes in phenobarbital group was higher than valproate group at 12-month (68.0% vs. 47.92%, P = 0.044). A total of 43 patients successfully participated cognitive and emotional tests. Mild cognitive impairment was found in 7.14% of phenobarbital group and 50.0% in valproate group (P = 0.026). In addition, there were no significant differences with respect to anxiety (36.36% vs. 38.10%) and depression (31.82% vs. 47.62%) between the phenobarbital and valproate groups.

CONCLUSIONS

Combined with long term conventional therapy, intravenous phenobarbital group had more good outcomes than intravenous valproate group in Chinese adult patients with GCSE up to 12-month follow-up. This finding may prompt the option of intravenous phenobarbital especially in patients with limited access to new antiseizure drugs.

Milestones in the history of neurocritical care

Over the last century, significant milestones have been achieved in managing critical illness and diagnosing and treating neurological diseases. Building upon these milestones, the field of neurocritical care emerged in the 1980 and 1990 s at the convergence of critical care medicine and acute neurological treatment. This comprehensive review presents a historical account of key developments in neurocritical care in both the United States and Europe, with a special emphasis on German contributions. The scope of the review encompasses: the foundations of neurocritical care, including post-operative units in the 1920s and 30s, respiratory support during the poliomyelitis epidemics in the 40 and 50 s, cardiac and hemodynamic care in the 60 and 70 s, and stroke units in the 80 and 90 s; key innovations including cerebral angiography, computed tomography, and intracranial pressure and multi-modal monitoring; and advances in stroke, traumatic brain injury, cardiac arrest, neuromuscular disorders, meningitis and encephalitis. These advances have revolutionized the management of neurological emergencies, emphasizing interdisciplinary teamwork, evidence-based protocols, and personalized approaches to care.

Clonazepam Loading Dose in Status Epilepticus: Is More Always Better?

BACKGROUND AND OBJECTIVES

Benzodiazepines are the first treatment line in status epilepticus (SE). Despite their well-established benefit, benzodiazepines are frequently underdosed with potential detrimental consequences. In some European countries, clonazepam (CLZ) is commonly used as the first line treatment. The aim of this study was to explore the correlation between CLZ loading doses and SE outcome.

METHODS

This study included a retrospective analysis of a prospective registry in Lausanne, Switzerland (CHUV Lausanne University Hospital), including all SE episodes treated between February 2016 and February 2021. Only adults (> 16 years old) were included with CLZ used as the first treatment line. Post-anoxic SE were excluded because of significant differences in physiopathology and prognosis. Patient characteristics, SE features, the validated SE severity score (STESS), and treatment characteristics were prospectively recorded. We considered loading doses of 0.015 mg/kg or higher (following commonly recommended loading doses) as high doses. We analyzed outcome in terms of number of treatment lines after the CLZ, proportion of refractory episodes, intubation for airways protection, intubation for SE treatment, and mortality. We performed univariable analyses to investigate the association between loading doses and clinical response. A multivariable stepwise backward binary logistic regression was applied for adjusting for potential confounders. Multivariable linear regression was similarly used to analyze CLZ dose as a continuous variable.

RESULTS

We collected 251 SE episodes in 225 adult patients. Median CLZ loading dose was 0.010 mg/kg. CLZ high doses were used in 21.9% of SE episodes (in 43.8% for > 80% of the high dose). Thirteen percent of patients with SE were intubated for airways control, while intubation was needed in 12.7% for SE treatment. High CLZ loading doses were independently associated with younger age (median 62 versus 68 years old, p = 0.002), lesser weight (65 kg versus 75 kg, p = 0.001) and more frequent intubation for airways protection (23% vs 11%, p = 0.013), but differing CLZ dose was not associated with any outcome parameter.

CONCLUSION

CLZ high doses were more frequently used for SE treatment in younger patients with healthy weight and were more often associated with intubation for airways protection, probably as an adverse event. Varying CLZ dose did not alter outcome in SE, raising the possibility that commonly recommended doses are above what is needed, at least in some patients. Our results suggest that CLZ doses in SE may be individualized depending on the clinical setting.

Management of convulsive status epilepticus: recent updates

Convulsive status epilepticus (SE) is a medical emergency associated with high morbidity and mortality. Recently, clinical trials and meta-analyses investigating medical treatment of SE have been published. Benzodiazepine is well known as the first-line treatment for SE. Recent evidence suggests the equivalence of intravenous fosphenytoin, valproate, and levetiracetam for treatment of established SE. There is lack of evidence regarding treatment for refractory SE. Intravenous midazolam is commonly used, and recent evidence supports the use of ketamine. Additional studies are needed to improve the management of convulsive SE.

Status epilepticus and benzodiazepine treatment: Use, underdosing and outcome - insights from a retrospective, multicentre registry

OBJECTIVE

To explore the reasons for and outcomes of non- or undertreatment with benzodiazepines (BZDs) in status epilepticus (SE).

METHODS

We retrospectively analysed all SE patients from the urban area of Cologne over two years.

RESULTS

328 SE patients were eligible, and only 72% were initially treated with BZDs. Of these, only 21.6% were treated sufficiently with BZDs according to current guidelines. SE patients not initially treated with BZDs were significantly older, had less often known epilepsy, had a prolonged arrival time to the emergency room, and presented more often with a non-generalised convulsive semiology. Regarding adequate dosages, patients with a generalised convulsive SE seemed to benefit from a sufficient BZD dosing with significantly shortened mean ventilation duration (37.1 to 208 h), decreased mean intensive care unit (1.7 to 5 days) and in-hospital stay (4.1 to 8.8 days). In contrary, aggressive BZD treatment in non-generalised convulsive SE resulted in a longer inpatient stay (9.2 to 5.8 days) and lower favourable outcome rates at discharge (16% to 63%).

CONCLUSIONS

The current SE treatment guidelines for first-line BZD therapy in SE were violated in most patients. Sufficient BZD dosing was beneficial in generalised convulsive SE, but not in other forms of SE. SE semiology might be crucial for treatment decisions with BZDs. Further treatment evidence especially in non-generalised convulsive SE is urgently needed.

Electroencephalographic patterns in a mechanically ventilated cat with permethrin intoxication

Case summary

A 1-year-old male castrated domestic shorthair cat was presented in a condition of status epilepticus following incidental permethrin spot-on administration by its owner. General anaesthesia and mechanical positive pressure control ventilation were necessary to control the epileptic seizures and a progressive condition of hypoventilation. The cat was managed with an intravenous constant rate infusion of midazolam, propofol and ketamine associated with a low-dose intravenous lipid emulsion. A condition of non-convulsive status epilepticus was detected by serial continuous electroencephalogram (cEEG) monitoring. Initial cEEG showed paroxysmal epileptiform discharges; thus, antiseizure treatment with phenobarbital was added and a bolus of hypertonic saline solution was administered to treat suspected intracranial hypertension. A second cEEG performed 24 h later showed the presence of rare spikes and a burst-suppression pattern, so the decision was made to discontinue propofol. A third cEEG, 72 h post-hospitalisation, showed a normal encephalographic pattern; therefore, anaesthetic drugs were progressively tapered, and the patient was extubated. Five days after admission the cat was discharged on phenobarbital treatment, which was gradually tapered during the following months.

Relevance and novel information

This is the first reported case to describe cEEG monitoring during hospitalisation for feline permethrin intoxication. cEEG should be encouraged in cats with altered mental status that have previously suffered cluster seizures or status epilepticus, which could guide clinicians in the choice of antiseizure drugs.

In the fast lane: Receptor trafficking during status epilepticus

Status epilepticus (SE) remains a significant cause of morbidity and mortality and often is refractory to standard first-line treatments. A rapid loss of synaptic inhibition and development of pharmacoresistance to benzodiazepines (BZDs) occurs early during SE, while NMDA and AMPA receptor antagonists remain effective treatments after BZDs have failed. Multimodal and subunit-selective receptor trafficking within minutes to an hour of SE involves GABA-A, NMDA, and AMPA receptors and contributes to shifts in the number and subunit composition of surface receptors with differential impacts on the physiology, pharmacology, and strength of GABAergic and glutamatergic currents at synaptic and extrasynaptic sites. During the first hour of SE, synaptic GABA-A receptors containing γ2 subunits move to the cell interior while extrasynaptic GABA-A receptors with δ subunits are preserved. Conversely, NMDA receptors containing N2B subunits are increased at synaptic and extrasynaptic sites, and homomeric GluA1 ("GluA2-lacking") calcium permeant AMPA receptor surface expression also is increased. Molecular mechanisms, largely driven by NMDA receptor or calcium permeant AMPA receptor activation early during circuit hyperactivity, regulate subunit-specific interactions with proteins involved with synaptic scaffolding, adaptin-AP2/clathrin-dependent endocytosis, endoplasmic reticulum (ER) retention, and endosomal recycling. Reviewed here is how SE-induced shifts in receptor subunit composition and surface representation increase the excitatory to inhibitory imbalance that sustains seizures and fuels excitotoxicity contributing to chronic sequela such as "spontaneous recurrent seizures" (SRS). A role for early multimodal therapy is suggested both for treatment of SE and for prevention of long-term comorbidities.

The Roles of Glutamate Receptors and Their Antagonists in Status Epilepticus, Refractory Status Epilepticus, and Super-Refractory Status Epilepticus

Status epilepticus (SE) is a neurological emergency with a high mortality rate. When compared to chronic epilepsy, it is distinguished by the durability of seizures and frequent resistance to benzodiazepine (BZD). The Receptor Trafficking Hypothesis, which suggests that the downregulation of γ-Aminobutyric acid type A (GABAA) receptors, and upregulation of N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors play major roles in the establishment of SE is the most widely accepted hypothesis underlying BZD resistance. NMDA and AMPA are ionotropic glutamate receptor families that have important excitatory roles in the central nervous system (CNS). They are both essential in maintaining the normal function of the brain and are involved in a variety of neuropsychiatric diseases, including epilepsy. Based on animal and human studies, antagonists of NMDA and AMPA receptors have a significant impact in ending SE; albeit most of them are not yet approved to be in clinically therapeutic guidelines, due to their psychomimetic adverse effects. Although there is still a dearth of randomized, prospective research, NMDA antagonists such as ketamine, magnesium sulfate, and the AMPA antagonist, perampanel, are regarded to be reasonable optional adjuvant therapies in controlling SE, refractory SE (RSE) or super-refractory SE (SRSE), though there are still a lack of randomized, prospective studies. This review seeks to summarize and update knowledge on the SE development hypothesis, as well as clinical trials using NMDA and AMPA antagonists in animal and human studies of SE investigations.

Phenobarbital in Status epilepticus - Rediscovery of an effective drug

Phenobarbital (PB) is one of the oldest Antiseizure Medicines (ASMs), which is in clinical use since 1912. Its value in the treatment of Status epilepticus is currently discussed controversially. Phenobarbital has fallen out of favor in many countries across Europe because of reports of hypotension, arrhythmias, and hypopnea. Phenobarbital has a strong antiseizure effect with remarkably little sedation. It exerts its clinical effects, through the increase of GABE-ergic inhibition and decrease of glutamatergic excitation by inhibition of AMPA receptors. Despite good preclinical evidence, there are remarkably few randomized controlled studies on humans in SE, which suggest, that it is at least as good as lorazepam in first-line treatment in early SE, and significantly better than valproic acid in benzodiazepine-resistant SE. Data from randomized trials and large non-randomized prospective and retrospective studies suggest, that Phenobarbital is well tolerated even if used in very high dose protocols. Thus, despite its decline in its popularity at least in Europe and North America, it should be considered a highly cost-effective treatment for early and established SE, not only in resource-limited settings. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.

Specific profiles of new-onset vs. non-inaugural status epilepticus: From diagnosis to 1-year outcome

While new-onset status epilepticus (NOSE) is a harbinger of chronic epilepsy, prospective medical data are sparse in terms of specifying whether the evolution of status epilepticus (SE) and seizure expression in NOSE resembles what occurs in patients who have already been diagnosed with epilepsy [non-inaugural SE (NISE)] in all aspects apart from its inaugural nature. The aim of this study was to compare the clinical, MRI, and EEG features that could distinguish NOSE from NISE. We conducted a prospective monocentric study in which all patients ≥18 years admitted for SE over a 6-month period were included. A total of 109 patients (63 NISE and 46 NOSE cases) were included. Despite similar modified Rankin scores before SE, several aspects of the clinical history distinguished NOSE from NISE patients. NOSE patients were older and frequently had neurological comorbidity and preexisting cognitive decline, but they had a similar prevalence of alcohol consumption to NISE patients. NOSE and NISE evolve in the same proportions as refractory SE (62.5% NOSE, 61% NISE) and share common features such as the same incidence (33% NOSE, 42% NISE, and p = 0.53) and volumes of peri-ictal abnormalities on MRI. However, in NOSE patients, we observed greater non-convulsive semiology (21.7% NOSE, 6% NISE, and p = 0.02), more periodic lateral discharges on EEG (p = 0.004), later diagnosis, and higher severity according to the STESS and EMSE scales (p < 0.0001). Mortality occurred in 32.6% of NOSE patients and 21% of NISE patients at 1 year (p = 0.19), but with different causes of death occurring at different time points: more early deaths directly linked to SE at 1 month occurred in the NOSE group, while there were more remote deaths linked to causal brain lesions in the NISE group at final follow-up. In survivors, 43.6% of the NOSE cases developed into epilepsy. Despite acute causal brain lesions, the novelty related to its inaugural nature is still too often associated with a delay in diagnosing SE and a poorer outcome, which justifies the need to more clearly specify the various types of SE to constantly raise awareness among clinicians. These results highlight the relevance of including novelty-related criteria, clinical history, and temporality of occurrence in the nosology of SE.

Evaluation of intravenous lorazepam dosing strategies and the incidence of refractory status epilepticus

INTRODUCTION

Status epilepticus (SE) is a neurological emergency associated with high mortality if not identified and treated promptly. For the emergent treatment of SE, the recommended intravenous (IV) lorazepam dose is 0.1 mg/kg/dose, up to a maximum of 4 mg. It has been shown that lorazepam is commonly under dosed in SE, but there is conflicting data on whether this has a negative impact on patient outcomes. This study assessed any dose less than 4 mg to help identify the effects of under dosing lorazepam in SE.

METHODS

This was a retrospective cohort study of patients admitted to a quaternary health system between October 1, 2017 and September 30, 2019 that experienced SE and were initially treated with IV lorazepam. Patients were divided into two cohorts, less than 4 mg or 4 mg, based on the initial one-time dose of lorazepam received. The primary outcome was the proportion of patients that progressed to refractory status epilepticus (RSE) that received an initial IV lorazepam dose of 4 mg compared to less than 4 mg for the treatment of SE. Secondary outcomes evaluated include length of stay, mortality, time in SE, number of seizures, cumulative lorazepam dose prior to urgent therapy, number of lorazepam doses prior to urgent therapy, time to urgent therapy, appropriately dosed urgent therapy, and number of antiepileptic drugs given in SE.

RESULTS

One hundred twenty patients were included in this study (107 patients received less than 4 mg and 13 patients received 4 mg). All patients included in the study were greater than 40 kg. The primary outcome of progression to RSE was observed in a significantly greater proportion of patients in the less than 4 mg group compared to the 4 mg group (93 [87%] vs. 8 [62%], p = 0.03). There was no difference in hospital or intensive care unit length of stay. However, there was an increased rate of in-hospital mortality in patients who received 4 mg compared to less than 4 mg (5 [39%] vs. 12[11%], p = 0.02).

DISCUSSION

The majority of patients in the study received less than the recommended dose of IV lorazepam for SE. Patients who received less than 4 mg experienced an increased progression to RSE, which supports current guideline recommended dosing. While there was an increased rate of mortality in patients who received 4 mg compared to less than 4 mg, time in SE was prolonged in the patient population and severity of illness was only available for a limited number of patients included.

Status Epilepticus in Older Adults: Diagnostic and Treatment Considerations

Status epilepticus (SE) is one of the leading life-threatening neurological emergencies in the elderly population, with significant morbidity and mortality. SE presents unique diagnostic and therapeutic challenges in the older population given overlap with other causes of encephalopathy, complicating diagnosis, and the common occurrence of multiple comorbid diseases complicates treatment. First-line therapy involves the use of rescue benzodiazepine in the form of intravenous lorazepam or diazepam, intramuscular or intranasal midazolam and rectal diazepam. Second-line therapies include parenteral levetiracetam, fosphenytoin, valproate and lacosamide, and underlying comorbidities guide the choice of appropriate medication, while third-line therapies may be influenced by the patient's code status as well as the cause and type of SE. The standard of care for convulsive SE is treatment with an intravenous anesthetic, including midazolam, propofol, ketamine and pentobarbital. There is currently limited evidence guiding appropriate therapy in patients failing third-line therapies. Adjunctive strategies may include immunomodulatory treatments, non-pharmacological strategies such as ketogenic diet, neuromodulation therapies and surgery in select cases. Surrogate decision makers should be updated early and often in refractory episodes of SE and informed of the high morbidity and mortality associated with the disease as well as the high probability of subsequent epilepsy among survivors.

Valproic acid as adjuvant treatment for convulsive status epilepticus: a randomised clinical trial

BACKGROUND

Generalised convulsive status epilepticus (GCSE) is a medical emergency. Guidelines recommend a stepwise strategy of benzodiazepines followed by a second-line anti-seizure medicine (ASM). However, GCSE is uncontrolled in 20-40% patients and is associated with protracted hospitalisation, disability, and mortality. The objective was to determine whether valproic acid (VPA) as complementary treatment to the stepwise strategy improves the outcomes of patients with de novo established GCSE.

METHODS

This was a multicentre, double-blind, randomised controlled trial in 244 adults admitted to intensive care units for GCSE in 16 French hospitals between 2013 and 2018. Patients received standard care of benzodiazepine and a second-line ASM (except VPA). Intervention patients received a 30 mg/kg VPA loading dose, then a 1 mg/kg/h 12 h infusion, whilst the placebo group received an identical intravenous administration of 0.9% saline as a bolus and continuous infusion. Primary outcome was proportion of patients discharged from hospital by day 15. The secondary outcomes were seizure control, adverse events, and cognition at day 90.

RESULTS

A total of 126 (52%) and 118 (48%) patients were included in the VPA and placebo groups. 224 (93%) and 227 (93%) received a first-line and a second-line ASM before VPA or placebo infusion. There was no between-group difference for patients hospital-discharged at day 15 [VPA, 77 (61%) versus placebo, 72 (61%), adjusted relative risk 1.04; 95% confidence interval (0.89-1.19); p = 0.58]. There were no between-group differences for secondary outcomes.

CONCLUSIONS

VPA added to the recommended strategy for adult GCSE is well tolerated but did not increase the proportion of patients hospital-discharged by day 15.

TRIAL REGISTRATION NO

NCT01791868 (ClinicalTrials.gov registry), registered: 15 February 2012.

Optimizing Status Epilepticus Management in the Emergency Department: It's About Time

Status epilepticus (SE) is a frequent medical emergency that requires expedited treatment to avoid the ensuing high incidence of morbidity and mortality associated with prolonged seizures. Protracted seizure duration itself has the potential to result in maladaptive neuronal responses that can not only further increase seizure duration and worsen clinical outcomes but also lead to reduced responsiveness to pharmacotherapy. Benzodiazepines are consistently recommended as first-line treatment due to their rapid onset and efficacy in terminating seizures, followed by the emergent administration of an antiepileptic drug (AED). Various benzodiazepine and AED options are recommended and can be utilized in this setting, all with their own unique advantages and challenges. With time at a premium, agents should be selected that can be rapidly administered and have an advantageous pharmacokinetic profile in order to limit seizure duration and optimize outcomes. The intent of this review is to provide an outline of the importance of time-to-treatment implementation in this setting, assess the landscape of options that may provide timing advantages, and examine potential strategies for deploying expeditious therapy.

Has the mortality of status epilepticus changed over the past few decades?

Earlier and more aggressive treatment of status epilepticus has long been established orthodoxy. In addition to increasing therapeutic options, it is of critical importance to understand whether or not this has translated into improved prognosis. In this review, we examine the evidence as to whether the mortality of convulsive status epilepticus changed over the past few decades. In particular, we discuss a recent systematic review and meta-analysis examining this question and its implications. We discuss potential reasons why there is no evidence of improved prognosis in terms of mortality and ways in which this may be addressed. Finally, we advocate the urgent need for accurate data on functional outcomes in non-fatal cases of status epilepticus. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.

Novel variants in GABA(A) receptor subunits: A possible association with benzodiazepine resistance in patients with drug-resistant epilepsy

Benzodiazepines (BDZ) such as diazepam and lorazepam are popular as first-line treatment for acute seizures due to their rapid action and high efficacy. However, long-term usage of BDZ leads to benzodiazepine resistance, a phenomenon whose underlying mechanisms are still being investigated. One of the hypothesised mechanisms contributing to BDZ resistance is the presence of mutations in benzodiazepine-sensitive receptors. While a few genetic variants have been reported previously, knowledge of relevant pathogenic variants is still scarce. We used Sanger Sequencing to detect variants in the ligand-binding domain of BDZ-sensitive GABA_A receptor subunits α1-3 and 5 expressed in resected brain tissues of drug-resistant epilepsy (DRE) patients with a history of BDZ resistance and found two previously unreported predicted pathogenic frameshifting variants - NM_000807.4(GABRA2):c.367_368insG and NM_000810.4(GABRA5):c.410del - significantly enriched in these patients. The findings were further explored in resected DRE brain tissues through cellular electrophysiological experiments.

Levetiracetam versus fosphenytoin as a second-line treatment after diazepam for adult convulsive status epilepticus: a multicentre non-inferiority randomised control trial

OBJECTIVE

Status epilepticus (SE) is an emergency condition for which rapid and secured cessation is crucial. Although fosphenytoin (FPHT) is recommended as a second-line treatment, levetiracetam (LEV) reportedly has similar efficacy, but higher safety. Therefore, we herein compared LEV with FPHT in adult SE.

METHODS

We initiated a multicentre randomised control trial in emergency departments with adult patients with convulsive SE. Diazepam was initially administered, followed intravenously by FPHT at 22.5 mg/kg or LEV at 1000-3000 mg. The primary outcome was assigned as the seizure cessation rate within 30 min of the administration of the study drug.

RESULTS

A total of 176 adult patients with SE were enrolled (82 FPHT and 94 LEV), and 3 were excluded from the full analysis set. Seizure cessation rates within 30 min were 83.8% (67/80) in the FPHT group and 89.2% (83/93) in the LEV group. The difference in these rates was 5.5% (95% CI -4.7 to 15.7, p=0.29). The non-inferiority of LEV to FPHT was confirmed with p<0.001 by the Farrington-Manning test. No significant differences were observed in the seizure recurrence rate or intubation rate within 24 hours. Serious adverse events developed in three patients in the FPHT group and none in the LEV group (p=0.061).

CONCLUSION

The efficacy of LEV was similar to that of FPHT for adult SE following the administration of diazepam. LEV may be recommended as a second-line treatment for SE along with phenytoin/FPHT.

TRIAL REGISTRATION NUMBER

jRCTs031190160.

Reponse of second-line treatment in focal status epilepticus: A tertiary hospital experience

OBJECTIVE

To investigate the response to various antiseizure medications (ASMs) in the treatment of focal status epilepticus (SE) in the established phase, and the effect of administering several ASMs prior to sedation.

METHODS

All SE cases in patients aged > 16 years treated with non-BZDs ASMs were prospectively collected in our centre from February 2011 to April 2019. In total, 281 episodes were analysed.

RESULTS

Median age at SE onset was 65.1 years; 47 % were focal motor and 53 % focal non-motor episodes. SE cessation was achieved in 79 % episodes with second-line drugs, whereas a third line (anesthetics) was required in 47 episodes. SE cessation was achieved in only 27 % with the first ASM, 48 % with the second, and 51 % with the third. Prompt resolution of the SE episode with a first or second ASM was associated with a better outcome than episodes requiring a larger number of drugs (p = 0.024). The first option in our sample was levetiracetam in 70 % of cases. Among the total of non-responding SE cases treated with levetiracetam as the first ASM option, 107 were subsequently given lacosamide (seizure cessation in 53.3 %) and 34 valproic acid (seizure cessation in 29.4 %) (p = 0.015).

CONCLUSION

Our findings further support the notion that early termination of SE with a first or second ASM confers a better functional outcome. The large difference in response between the first ASM and consecutive ones suggests that the sum of different ASMs might be the key to resolving focal SE.

Co-Occurring Psychopathology Moderates Social Skills Improvement in a Randomized Controlled Trial of a Collaborative School-Home Intervention for Children with ADHD

OBJECTIVE

Children with ADHD often exhibit marked impairment in their social skills, but evidence-based psychosocial interventions for ADHD have shown limited efficacy in remediating these deficits. Co-occurring psychopathology exacerbates social deficits in children with ADHD and is a plausible moderator of treatment response. To identify factors contributing to variable social skills treatment response, we examined co-occurring externalizing, depression, and anxiety symptoms as moderators of social skills outcomes in a randomized controlled trial of the Collaborative Life Skills (CLS) program, an evidence-based collaborative school-home ADHD intervention.

METHOD

Participants were 159 children with ADHD (M age = 8.35 years, 28.3% female) at 27 schools in an urban public school district. Twenty-three schools were randomly assigned to CLS or usual services, with an additional four schools assigned to Spanish-adapted CLS or usual services. Multi-informant measures of co-occurring psychopathology and social skills were collected at baseline and post-treatment.

RESULTS

Parent-rated externalizing and depression symptoms moderated treatment effects on social skills, whereby higher symptomatology in each domain was unrelated to social skills improvement in the CLS group but predicted worsening social skills in response to usual services. In contrast, teacher-rated anxiety moderated treatment effects on social skills, whereby higher anxiety predicted greater social skills improvement in response to CLS but was unrelated to social skills outcomes following usual services.

CONCLUSIONS

Findings reflect novel evidence that child psychopathology domains exhibit unique moderating effects on social skills treatment response in children with ADHD. We discuss implications for optimizing evidence-based interventions to target social impairment in this population.

Out-of-hospital versus in-hospital status epilepticus: the role of etiology and comorbidities

Background and purpose

Our objectives were to identify differences in clinical characteristics between patients with out‐of‐hospital and in‐hospital status epilepticus (SE) onset, and to evaluate the influence of SE onset setting on 30‐day mortality and SE cessation.

Methods

We included consecutive patients with SE admitted from 2013–2021 at Modena Academic Hospital. A propensity score was obtained with clinical variables unevenly distributed between the two groups.

Results

Seven hundred eleven patients were included; 55.8% (397/711) with out‐of‐hospital and 44.2% (314/711) with in‐hospital onset. Patients with in‐hospital SE onset were older and had a higher frequency of comorbidities, acute and/or potentially fatal etiologies, impaired consciousness before treatment, and nonconvulsive or myoclonic SE. No difference was found in SE cessation between the groups. Patients with in‐hospital SE had higher 30‐day mortality (127/314, 62.9% vs. 75/397, 37.1%; p < 0.001). In‐hospital onset was an independent risk factor for 30‐day mortality (adjusted odds ratio = 1.720; 95% confidence interval = 1.107–2.674; p = 0.016). In the propensity group (n = 244), no difference was found in 30‐day mortality and SE cessation between out‐of‐hospital and in‐hospital SE onset groups (36/122, 29.5% vs. 34/122, 27.9%; p = 0.888; and 47/122, 38.5% vs. 39/122; 32%; p = 0.347, respectively).

Conclusions

In‐hospital SE is associated with higher 30‐day mortality without difference in SE cessation. The two groups differ considerably for age, acute and possibly fatal etiologies, comorbidities, and SE semiology. The patient location at SE onset is an important prognostic predictor. However, the increased mortality is probably unrelated to the setting of SE onset and reflects intrinsic prognostic predictors.

Prognostic indicators of non-convulsive status epilepticus in intensive care unit

BACKGROUND

To determine the rate of non-convulsive status epilepticus with/without prominent motor phenomena (SE-PM/ NCSE) and predictive value of electroclinical findings of continious electroencephalography (cEEG) monitoring of these patients and its association with prognosis in intensive care units (ICU).

METHODS

We retrospectively collected data of 218 patients whose cEEG was performed in ICU between 2016 and 2018. The cEEG for NCSE diagnosis was evaluated according to Salzburg Consensus Criteria (SCC).

RESULTS

The mean age of patients was 57.09 ± 18.9 (16-95) years and 49.1% (107) were female. Of 218 patients, 32 (14.7%) had SE-PM/NCSE. According to SCC the rate of NCSE (NCSE + possible NCSE) was 9.6% (n = 21). Prior to cEEG recording, 38.9% (n = 85) of overall patients had a history of seizure/convulsion, and 22.7% (n = 21) of these patients diagnosed with NCSE based on cEEG. The mortality rates in critically ill patients were 41.3% (30.8%, 42.8%; for SE-PM and NCSE respectively). Prognosis was associated with age, epilepsy diagnosis, having convulsion/seizure history on follow-up, GCS, need for ventilation, kind of drugs, sepsis diagnosis, and minimum frequency of background activity of the cEEG (p = 0.001, 0.002, 0.001, 0.020, 0.001, 0.001, 0.001, 0.0001 respectively).

CONCLUSIONS

NCSE findings are mostly found in patients who were comatose and had seizure/convulsion history on follow-up. Mortality is higher in patients diagnosed with NCSE followed in the ICU compared to SE-PM.

Why won't it stop? The dynamics of benzodiazepine resistance in status epilepticus

Status epilepticus is a life-threatening neurological emergency that affects both adults and children. Approximately 36% of episodes of status epilepticus do not respond to the current preferred first-line treatment, benzodiazepines. The proportion of episodes that are refractory to benzodiazepines is higher in low-income and middle-income countries (LMICs) than in high-income countries (HICs). Evidence suggests that longer episodes of status epilepticus alter brain physiology, thereby contributing to the emergence of benzodiazepine resistance. Such changes include alterations in GABA_A receptor function and in the transmembrane gradient for chloride, both of which erode the ability of benzodiazepines to enhance inhibitory synaptic signalling. Often, current management guidelines for status epilepticus do not account for these duration-related changes in pathophysiology, which might differentially impact individuals in LMICs, where the average time taken to reach medical attention is longer than in HICs. In this Perspective article, we aim to combine clinical insights and the latest evidence from basic science to inspire a new, context-specific approach to efficiently managing status epilepticus.

Status epilepticus: review on diagnosis, monitoring and treatment

Status epilepticus (SE) is a frequent neurological emergency associated with high morbidity and mortality. According to the new ILAE 2015 definition, SE results either from the failure of the mechanisms responsible for seizure termination or initiation, leading to abnormally prolonged seizures. The definition has different time points for convulsive, focal and absence SE. Time is brain. There are changes in synaptic receptors leading to a more proconvulsant state and increased risk of brain lesion and sequelae with long duration. Management of SE must include three pillars: stop seizures, stabilize patients to avoid secondary lesions and treat underlying causes. Convulsive SE is defined after 5 minutes and is a major emergency. Benzodiazepines are the initial treatment, and should be given fast and an adequate dose. Phenytoin/fosphenytoin, levetiracetam and valproic acid are evidence choices for second line treatment. If SE persists, anesthetic drugs are probably the best option for third line treatment, despite lack of evidence. Midazolam is usually the best initial choice and barbiturates should be considered for refractory cases. Nonconvulsive status epilepticus has a similar initial approach, with benzodiazepines and second line intravenous (IV) agents, but after that, aggressiveness should be balanced considering risk of lesion due to seizures and medical complications caused by aggressive treatment. Usually, the best approach is the use of sequential IV antiepileptic drugs (oral/tube are options if IV options are not available). EEG monitoring is crucial for diagnosis of nonconvulsive SE, after initial control of convulsive SE and treatment control. Institutional protocols are advised to improve care.

Improving epilepsy control among children with cerebral palsy in rural Bangladesh: a prospective cohort-based study

OBJECTIVE

To define the prevalence and seizure subtypes among children with cerebral palsy (CP) in rural Bangladesh and explore barriers to optimum epilepsy control.

DESIGN

Prospective cohort study.

SETTING

The study was conducted in Shahjadpur, a rural subdistrict of Bangladesh.

PARTICIPANTS

Children (<18 years) with CP and epilepsy identified using the Bangladesh CP Register (BCPR) in the study site.

METHODS

Assessments were conducted in three focused epilepsy clinics overseen by a paediatric neurologist between December 2016 and January 2018, with intervening phone and video-conference follow-ups. Details of event type, frequency and medication compliance were collected. Antiepileptic drugs (AEDs) were prescribed based on seizure type, family income, comorbidity and medication availability.

RESULTS

23.4% (170/726) of the BCPR cohort had a clinical diagnosis of epilepsy of whom 166 were assessed. Following the focused epilepsy clinics, 62.0% (103/166) children were clinically determined to have ongoing epileptic seizures. 62.1% (64/103) had generalised onset tonic clonic seizures, 27.2% (28/103) had focal onset seizures with impaired awareness and 10.7% (11/103) had other seizure types. None of the children with prolonged seizures (31/103) had an emergency seizure management plan. Non-epileptic events were being pharmacologically treated as seizures in 18.1% (30/166) children. Financial constraints were the main reason for non-compliance on follow-up.

CONCLUSIONS

Gaps in optimum epilepsy management in rural Bangladesh are amenable to improvement anchored with local healthcare workers. Training and clinical care focused on recognition of common seizure types, seizure mimics and rationalising use of available AEDs can be facilitated by better referral pathways and telehealth support.

Pre-hospital and emergency department treatment of convulsive status epilepticus in adults: an evidence synthesis

BACKGROUND

Convulsive status epilepticus is defined as ≥ 5 minutes of either continuous seizure activity or repetitive seizures without regaining consciousness. It is regarded as an emergency condition that requires prompt treatment to avoid hospitalisation and to reduce morbidity and mortality. Rapid pre-hospital first-line treatment of convulsive status epilepticus is currently benzodiazepines, administered either by trained caregivers in the community (e.g. buccal midazolam, rectal diazepam) or by trained health professionals via intramuscular or intravenous routes (e.g. midazolam, lorazepam). There is a lack of clarity about the optimal treatment for convulsive status epilepticus in the pre-hospital setting.

OBJECTIVES

To assess the current evidence on the clinical effectiveness and cost-effectiveness of treatments for adults with convulsive status epilepticus in the pre-hospital setting.

DATA SOURCES

We searched major electronic databases, including MEDLINE, EMBASE, PsycInfo®, CINAHL, CENTRAL, NHS Economic Evaluation Database, Health Technology Assessment Database, Research Papers in Economics, and the ISPOR Scientific Presentations Database, with no restrictions on publication date or language of publication. Final searches were carried out on 21 July 2020.

REVIEW METHODS

Systematic review of randomised controlled trials assessing adults with convulsive status epilepticus who received treatment before or on arrival at the emergency department. Eligible treatments were any antiepileptic drugs offered as first-line treatments, regardless of their route of administration. Primary outcomes were seizure cessation, seizure recurrence and adverse events. Two reviewers independently screened all citations identified by the search strategy, retrieved full-text articles, extracted data and assessed the risk of bias of the included trials. Results were described narratively.

RESULTS

Four trials (1345 randomised participants, of whom 1234 were adults) assessed the intravenous or intramuscular use of benzodiazepines or other antiepileptic drugs for the pre-hospital treatment of convulsive status epilepticus in adults. Three trials at a low risk of bias showed that benzodiazepines were effective in stopping seizures. In particular, intramuscular midazolam was non-inferior to intravenous lorazepam. The addition of levetiracetam to clonazepam did not show clear advantages over clonazepam alone. One trial at a high risk of bias showed that phenobarbital plus optional phenytoin was more effective in terminating seizures than diazepam plus phenytoin. The median time to seizure cessation from drug administration varied from 1.6 minutes to 15 minutes. The proportion of people with recurrence of seizures ranged from 10.4% to 19.1% in two trials reporting this outcome. Across trials, the rates of respiratory depression among participants receiving active treatments were generally low (from 6.4% to 10.6%). The mortality rate ranged from 2% to 7.6% in active treatment groups and from 6.2% to 15.5% in control groups. Only one study based on retrospective observational data met the criteria for economic evaluation; therefore, it was not possible to draw any robust conclusions on cost-effectiveness.

LIMITATIONS

The limited number of identified trials and their differences in terms of treatment comparisons and outcomes hindered any meaningful pooling of data. None of the included trials was conducted in the UK and none assessed the use of buccal midazolam or rectal diazepam. The review of economic evaluations was hampered by lack of suitable data.

CONCLUSIONS

Both intravenous lorazepam and intravenous diazepam administered by paramedics are more effective than a placebo in the treatments of adults with convulsive status epilepticus, and intramuscular midazolam is non-inferior to intravenous lorazepam. Large well-designed clinical trials are needed to establish which benzodiazepines are more effective and preferable in the pre-hospital setting.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42020201953.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Evidence Synthesis programme and will be published in full in Health Technology Assessment; Vol. 26, No. 20. See the NIHR Journals Library website for further project information.