Duration of therapeutic coma and outcome of refractory status epilepticus

Emergent Management of Status Epilepticus

OBJECTIVE

Status epilepticus is a neurologic emergency that can be life- threatening. The key to effective management is recognition and prompt initiation of treatment. Management of status epilepticus requires a patient-specific-approach framework, consisting of four axes: (1) semiology, (2) etiology, (3) EEG correlate, and (4) age. This article provides a comprehensive overview of status epilepticus, highlighting the current treatment approaches and strategies for management and control.

LATEST DEVELOPMENTS

Administering appropriate doses of antiseizure medication in a timely manner is vital for halting seizure activity. Benzodiazepines are the first-line treatment, as demonstrated by three randomized controlled trials in the hospital and prehospital settings. Benzodiazepines can be administered through IV, intramuscular, rectal, or intranasal routes. If seizures persist, second-line treatments such as phenytoin and fosphenytoin, valproate, or levetiracetam are warranted. The recently published Established Status Epilepticus Treatment Trial found that all three of these drugs are similarly effective in achieving seizure cessation in approximately half of patients. For cases of refractory and super-refractory status epilepticus, IV anesthetics, including ketamine and γ-aminobutyric acid-mediated (GABA-ergic) medications, are necessary. There is an increasing body of evidence supporting the use of ketamine, not only in the early phases of stage 3 status epilepticus but also as a second-line treatment option.

ESSENTIAL POINTS

As with other neurologic emergencies, "time is brain" when treating status epilepticus. Antiseizure medication should be initiated quickly to achieve seizure cessation. There is a need to explore newer generations of antiseizure medications and nonpharmacologic modalities to treat status epilepticus.

The Origin of the Burst-Suppression Paradigm in Treatment of Status Epilepticus

After electroencephalography (EEG) was introduced in hospitals, early literature recognized burst-suppression pattern (BSP) as a distinctive EEG pattern characterized by intermittent high-power oscillations alternating with isoelectric periods in coma and epileptic encephalopathies of childhood or the pattern could be induced by general anesthesia and hypothermia. The term was introduced by Swank and Watson in 1949 but was initially described by Derbyshire et al. in 1936 in their study about the anesthetic effects of tribromoethanol. Once the EEG/BSP pattern emerged in the literature as therapeutic goal in refractory status epilepticus, researchers began exploring whether the depth of EEG suppression correlated with improved seizure control and clinical outcomes. We can conclude that, from a historical perspective, the evidence to suppress the brain to a BSP when treating status epilepticus is inconclusive.

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.

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.

Seizure recurrences in generalized convulsive status epilepticus under sedation: What are its predictors and its impact on outcome?

BACKGROUND

Management of status epilepticus (SE) is focused on the early seizure termination. Refractory SE is an indication for sedation in patients with SE, but up to 75% of patients may be ventilated due to a neurological or respiratory failure. In patients requiring sedation, the clinical assessment is not sufficient to assess seizure control. Identifying those at risk of recurrent seizures could be useful to adapt their management. On the other hand, patients with low risk could benefit from an early withdrawal of sedation to avoid the impact of inappropriate sedation on outcome.

OBJECTIVE

To determine the prevalence and the predictors of uncontrolled SE and its impact on outcome in patients with generalized convulsive SE (GCSE) requiring mechanical ventilation (MV).

METHODS

We retrospectively included patients admitted to the intensive care unit with GCSE requiring MV. Uncontrolled SE was defined as persistent or recurrent seizures during sedation or within 24hours following withdrawal. A multivariable logistic regression model was used to assess the associated factors.

RESULTS

Uncontrolled SE occurred in 37 out of 220 patients (17%). Persistent seizures at admission, higher SAPS II and central nervous system infection were associated with a higher risk of uncontrolled SE. Acute toxic or metabolic etiologies were associated with a decreased risk of uncontrolled SE. In a supplementary analysis, decrease of albumin blood levels was associated with uncontrolled SE. Uncontrolled SE was associated with a poor functional outcome and mortality at 90 days.

CONCLUSIONS

Seventeen percent of patients with a GCSE requiring MV suffered from uncontrolled SE. Etiology and persistent seizures at admission were the main predictors of uncontrolled SE. Patients with uncontrolled SE had a longer duration of sedation and MV, a poor functional outcome and a higher mortality. Further studies are required to determine the impact of continuous electroencephalogram monitoring on the clinical course.

Duration of constant rate infusion with diazepam or propofol for canine cluster seizures and status epilepticus

Introduction

Constant rate infusion (CRI) of benzodiazepines or propofol (PPF) is a therapeutic option for cluster seizures (CS) and status epilepticus (SE) in canine patients non-responding to first-line benzodiazepines or non-anesthetics. However, specific indications for optimal duration of CRI are lacking. The aim of this study was to determine the effect of duration of anesthetic CRI on outcome and length of hospital stay in dogs with refractory seizure activity of different etiology.

Study design

Open-label non-randomized clinical trial.

Materials and methods

Seventy-three client-owned dogs were enrolled. Two groups [experimental (EXP) vs. control (CTRL)] were compared. The EXP group received diazepam (DZP) or PPF CRI for 12 h (±1 h) and the CTRL group received DZP or PPF CRI for 24 h (±1 h) in addition to a standardized emergency treatment protocol identical for both study groups. The historical control group was made up of a population of dogs already reported in a previously published paper by the same authors. Favorable outcome was defined as seizure cessation after CRI, no seizure recurrence, and clinical recovery. Poor outcome was defined as seizure recurrence, death in hospital or no return to acceptable clinical baseline. Univariate statistical analysis was performed.

Results

The study sample was 73 dogs: 45 (62%) received DZP CRI and 28 (38%) received PPF CRI. The EXP group was 39 dogs (25 DZP CRI and 14 PPF CRI) and the CTRL group 34 dogs (20 DZP CRI and 14 PPF CRI). We found no statistically significant difference in outcomes between the groups. The median length of stay was 56 h (IQR, 40-78) for the ALL EXP group and 58.5 h (IQR, 48-74.5) for the ALL CTRL group (p = 0.8).

Conclusion

Even though a shorter DZP or PPF CRI duration was not associated with a worse outcome, the study failed to identify a clear superiority of shorter CRI duration on outcome or length of hospital stay in dogs with refractory seizure activity of different etiology.

Effects of epileptiform activity on discharge outcome in critically ill patients in the USA: a retrospective cross-sectional study

BACKGROUND

Epileptiform activity is associated with worse patient outcomes, including increased risk of disability and death. However, the effect of epileptiform activity on neurological outcome is confounded by the feedback between treatment with antiseizure medications and epileptiform activity burden. We aimed to quantify the heterogeneous effects of epileptiform activity with an interpretability-centred approach.

METHODS

We did a retrospective, cross-sectional study of patients in the intensive care unit who were admitted to Massachusetts General Hospital (Boston, MA, USA). Participants were aged 18 years or older and had electrographic epileptiform activity identified by a clinical neurophysiologist or epileptologist. The outcome was the dichotomised modified Rankin Scale (mRS) at discharge and the exposure was epileptiform activity burden defined as mean or maximum proportion of time spent with epileptiform activity in 6 h windows in the first 24 h of electroencephalography. We estimated the change in discharge mRS if everyone in the dataset had experienced a specific epileptiform activity burden and were untreated. We combined pharmacological modelling with an interpretable matching method to account for confounding and epileptiform activity-antiseizure medication feedback. The quality of the matched groups was validated by the neurologists.

FINDINGS

Between Dec 1, 2011, and Oct 14, 2017, 1514 patients were admitted to Massachusetts General Hospital intensive care unit, 995 (66%) of whom were included in the analysis. Compared with patients with a maximum epileptiform activity of 0 to less than 25%, patients with a maximum epileptiform activity burden of 75% or more when untreated had a mean 22·27% (SD 0·92) increased chance of a poor outcome (severe disability or death). Moderate but long-lasting epileptiform activity (mean epileptiform activity burden 2% to <10%) increased the risk of a poor outcome by mean 13·52% (SD 1·93). The effect sizes were heterogeneous depending on preadmission profile-eg, patients with hypoxic-ischaemic encephalopathy or acquired brain injury were more adversely affected compared with patients without these conditions.

INTERPRETATION

Our results suggest that interventions should put a higher priority on patients with an average epileptiform activity burden 10% or greater, and treatment should be more conservative when maximum epileptiform activity burden is low. Treatment should also be tailored to individual preadmission profiles because the potential for epileptiform activity to cause harm depends on age, medical history, and reason for admission.

FUNDING

National Institutes of Health and National Science Foundation.

Propofol mitigates brain injury and oxidative stress, and enhances GABAA receptor α1 subunit expression in a rat model of lithium chloride-pilocarpine induced status epilepticus

Background/aim

Propofol is a positive allosteric modulator of GABAA receptor (GABAAR) and has potent antioxidant activity. The aim of this study was to investigate the effect of propofol on damage to the cerebral cortex and hippocampus in a lithium chloride (LiCl)-pilocarpine animal model of status epilepticus (SE).

Materials and methods

Adult male Sprague Dawley rats were injected with LiCl-pilocarpine to induce SE. They were then randomized and injected 30 min later with vehicle saline (SE+saline), propofol (SE+PPF, 50 mg/kg), Diazepam (SE+DZP, 10 mg/kg), Scopolamine (SE+SCOP, 10 mg/kg), or MK-801 (SE+MK-801, 2 mg/kg). Another group of rats received saline only and served as the naïve control (BLK). The levels of superoxide dismutase (SOD), glutathione (GSH) and malondialdehyde (MDA) in the serum, cortex and hippocampus were analyzed 2 and 24 h posttreatment. The degree of tissue damage in the cortex and hippocampus of individual rats was assessed 24 h posttreatment, together with expression of the GABAAR α1 subunit.

Results

The propofol group showed reduced levels of tissue damage in the cerebral cortex and hippocampus, decreased levels of MDA, and increased levels of GSH compared to the SE+saline group. No changes in SOD level were observed in serum and tissue samples from the cortex and hippocampus of SE+saline rats. Immunohistochemistry and Western blot assays showed that propofol treatment significantly increased the expression of GABAAR α1 subunit in the cortical and hippocampal tissues of SE rats.

Conclusion

Propofol treatment protected against SE-induced tissue injury in the cortex and hippocampus of rats. This was due at least in part to its antioxidant activity and to its induction of GABAAR α1 subunit expression in the brain.

A practical approach to in-hospital management of new-onset refractory status epilepticus/febrile infection related epilepsy syndrome

New-onset refractory status epilepticus (NORSE) is "a clinical presentation, not a specific diagnosis, in a patient without active epilepsy or other preexisting relevant neurological disorder, with new onset of refractory status epilepticus without a clear acute or active structural, toxic, or metabolic cause." Febrile infection related epilepsy syndrome (FIRES) is "a subcategory of NORSE that requires a prior febrile infection, with fever starting between 2 weeks and 24 h before the onset of refractory status epilepticus, with or without fever at the onset of status epilepticus." These apply to all ages. Extensive testing of blood and CSF for infectious, rheumatologic, and metabolic conditions, neuroimaging, EEG, autoimmune/paraneoplastic antibody evaluations, malignancy screen, genetic testing, and CSF metagenomics may reveal the etiology in some patients, while a significant proportion of patients' disease remains unexplained, known as NORSE of unknown etiology or cryptogenic NORSE. Seizures are refractory and usually super-refractory (i.e., persist despite 24 h of anesthesia), requiring a prolonged intensive care unit stay, often (but not always) with fair to poor outcomes. Management of seizures in the initial 24-48 h should be like any case of refractory status epilepticus. However, based on the published consensus recommendations, the first-line immunotherapy should begin within 72 h using steroids, intravenous immunoglobulins, or plasmapheresis. If there is no improvement, the ketogenic diet and second-line immunotherapy should start within seven days. Rituximab is recommended as the second-line treatment if there is a strong suggestion or proof of an antibody-mediated disease, while anakinra or tocilizumab are recommended for cryptogenic cases. Intensive motor and cognitive rehab are usually necessary after a prolonged hospital stay. Many patients will have pharmacoresistant epilepsy at discharge, and some may need continued immunologic treatments and an epilepsy surgery evaluation. Extensive research is in progress now via multinational consortia relating to the specific type(s) of inflammation involved, whether age and prior febrile illness affect this, and whether measuring and following serum and/or CSF cytokines can help determine the best treatment.

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.

When is it time for palliative and end-of-life care in status epilepticus?

Status epilepticus (SE) is a neurological emergency characterized by high rates of short-term and long-term morbidity and mortality. Status epilepticus seems to be a marker of the severity of other underlying conditions rather than a determinant of death on its own. Careful diagnosis and acute treatment of complications and causes of death to SE or its underlying etiology will enable the differentiation of SE patients that would benefit from different levels of treatment intensity. All SE patients should be treated actively with first- and second-line drugs as early as possible. For cases in which seizures continue after second-line treatment, the current guidelines fail to offer possibilities other than the active path with general anesthesia and intensive care unit (ICU) care. However, the intensity of care should be evaluated before starting ICU care or in unclear cases with the time-limited trial at ICU. There are now multiple possibilities for specialty palliative SE care that include sequential and add-on use of second-line drugs and palliative sedation at the ward. If ICU care is prolonged, the patient's status needs to be constantly re-evaluated and communicated to the family. When patients exhibit multiple predictors of mortality and poor functional outcomes, they should be allowed to have a natural death in a peaceful environment without unnecessarily prolonged suffering. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.

Constant rate infusion of diazepam or propofol for the management of canine cluster seizures or status epilepticus

INTRODUCTION

Cluster seizures (CS) and status epilepticus (SE) in dogs are severe neurological emergencies that require immediate treatment. Practical guidelines call for constant rate infusion (CRI) of benzodiazepines or propofol (PPF) in patients with seizures not responding to first-line treatment, but to date only few studies have investigated the use of CRI in dogs with epilepsy.

STUDY DESIGN

Retrospective clinical study.

METHODS

Dogs that received CRI of diazepam (DZP) or PPF for antiepileptic treatment during hospitalization at the Veterinary Teaching Hospital of the University of Turin for CS or SE between September 2016 and December 2019 were eligible for inclusion. Favorable outcome was defined as cessation of clinically visible seizure activity within few minutes from the initiation of the CRI, no seizure recurrence within 24 h after discontinuation of CRI through to hospital discharge, and clinical recovery. Poor outcome was defined as recurrence of seizure activity despite treatment or death in hospital because of recurrent seizures, catastrophic consequences of prolonged seizures or no return to an acceptable neurological and clinical baseline, despite apparent control of seizure activity. Comparisons between the number of patients with favorable outcome and those with poor outcome in relation to type of CRI, seizure etiology, reason for presentation (CS or SE), sex, previous AED therapy and dose of PPF CRI were carried out.

RESULTS

A total of 37 dogs, with 50 instances of hospitalization and CRI administered for CS or SE were included in the study. CRI of diazepam (DZP) or PPF was administered in 29/50 (58%) and in 21/50 (42%) instances of hospitalization, respectively. Idiopathic epilepsy was diagnosed in 21/37 (57%), (13/21 tier I and 8/21 tier II); structural epilepsy was diagnosed in 6/37 (16%) of which 4/6 confirmed and 2/6 suspected. A metabolic or toxic cause of seizure activity was recorded in 7/37 (19%). A total of 38/50 (76%) hospitalizations were noted for CS and 12/50 (24%) for SE. In 30/50 (60%) instances of hospitalization, the patient responded well to CRI with cessation of seizure activity, no recurrence in the 24 h after discontinuation of CRI through to hospital discharge, whereas a poor outcome was recorded for 20/50 (40%) cases (DZP CRI in 12/50 and PPF CRI in 8/50). Comparison between the number of patients with favorable outcome and those with poor outcome in relation to type of CRI, seizure etiology, reason for presentation (CS or SE), sex and previous AED therapy was carried out but no statistically significant differences were found.

CONCLUSIONS

The present study is the first to document administration of CRI of DZP or PPF in a large sample of dogs with epilepsy. The medications appeared to be tolerated without major side effects and helped control seizure activity in most patients regardless of seizure etiology. Further studies are needed to evaluate the effects of CRI duration on outcome and complications.

Management of Refractory Status Epilepticus: An International Cohort Study (MORSE CODe) Analysis of Patients Managed in the ICU

BACKGROUND AND OBJECTIVES

Status epilepticus that continues after the initial benzodiazepine and a second anticonvulsant medication is known as refractory status epilepticus (RSE). Management is highly variable because adequately powered clinical trials are missing. We aimed to determine whether propofol and midazolam were equally effective in controlling RSE in the intensive care unit, focusing on management in resource-limited settings.

METHODS

Patients with RSE treated with midazolam or propofol between January 2015 and December 2018 were retrospectively identified among 9 centers across 4 continents from upper-middle-income economies in Latin America and high-income economies in North America, Europe, and Asia. Demographics, Status Epilepticus Severity Score, etiology, treatment details, and discharge modified Rankin Scale (mRS) were collected. The primary outcome measure was good functional outcome defined as a mRS score of 0-2 at hospital discharge.

RESULTS

Three hundred eighty-seven episodes of RSE (386 patients) were included, with 162 (42%) from upper-middle-income and 225 (58%) from high-income economies. Three hundred six (79%) had acute and 79 (21%) remote etiologies. Initial RSE management included midazolam in 266 (69%) and propofol in 121 episodes (31%). Seventy episodes (26%) that were initially treated with midazolam and 42 (35%) with propofol required the addition of a second anesthetic to treat RSE. Baseline characteristics and outcomes of patients treated with midazolam or propofol were similar. Breakthrough (odds ratio [OR] 1.6, 95% CI 1.3-2.0) and withdrawal seizures (OR 2.0, 95% CI 1.7-2.5) were associated with an increased number of days requiring continuous intravenous anticonvulsant medications (cIV-ACMs). Prolonged EEG monitoring was associated with fewer days of cIV-ACMs (1-24 hours OR 0.5, 95% CI 0.2-0.9, and >24 hours OR 0.7, 95% CI 0.5-1.0; reference EEG <1 hour). This association was seen in both, high-income and upper-middle-income economies, but was particularly prominent in high-income countries. One hundred ten patients (28%) were dead, and 80 (21%) had good functional outcomes at hospital discharge.

DISCUSSION

Outcomes of patients with RSE managed in the intensive care unit with propofol or midazolam infusions are comparable. Prolonged EEG monitoring may allow physicians to decrease the duration of anesthetic infusions safely, but this will depend on the implementation of RSE management protocols. Goal-directed management approaches including EEG targets may hold promise for patients with RSE.

CLASSIFICATION OF EVIDENCE

This study provides Class III data that propofol and midazolam are equivalently efficacious for RSE.

Management of status epilepticus: a narrative review

Status epilepticus causes prolonged or repetitive seizures that, if left untreated, can lead to neuronal injury, severe disability, coma and death in paediatric and adult populations. While convulsive status epilepticus can be diagnosed using clinical features alone, non-convulsive status epilepticus requires confirmation by electroencephalogram. Early seizure control remains key in preventing the complications of status epilepticus. This is especially true for convulsive status epilepticus, which has stronger evidence supporting the benefit of treatment on outcomes. When status epilepticus becomes refractory, often due to gamma-aminobutyric acid and N-methyl-D-aspartate receptor modulation, anaesthetic drugs are needed to suppress seizure activity, of which there is limited evidence regarding the selection, dose or duration of their use. Seizure monitoring with electroencephalogram is often needed when patients do not return to baseline or during anaesthetic wean; however, it is resource-intensive, costly, only available in highly specialised centres and has not been shown to improve functional outcomes. Thus, the treatment goals and aggressiveness of therapy remain under debate, especially for non-convulsive status epilepticus, where prolonged therapeutic coma can lead to severe complications. This review presents an evidence-based, clinically-oriented and comprehensive review of status epilepticus and its definitions, aetiologies, treatments, outcomes and prognosis at different stages of the patient's journey.

Frequency and Types of Complications Encountered in Patients With Nonconvulsive Status Epilepticus in the Neurological ICU: Impact on Outcome

Objectives. The frequency and types of complications in patients with nonconvulsive status epilepticus (NCSE) who are followed up in the intensive care unit (ICU), and the impact of these complications on outcome are not well-known. We investigated the complications and their effects on prognosis in NCSE patients. Methods. After reviewing the video-EEG monitoring (VEEGM) reports of all the consecutive patients who were followed up in our ICU between 2009 and 2019, we identified two groups of patients: 1-patients with NCSE (study group) and 2-patients who underwent VEEGM for possible NCSE but did not have ictal recordings (no-NCSE group). Electronic health records were reviewed to identify demographic and clinical data, duration of ICU care, medical and surgical complications, pharmacologic treatment, and outcome. These parameters were compared statistically between the groups. We also investigated the parameters affecting prognosis at discharge. Results. Thirty-two patients with NCSE comprised the study group. Infection developed in 84%. More than half were intubated, had tracheostomy or percutaneous endoscopic gastrostomy application. Refractory NCSE was associated with significantly more frequent complications and worse outcome. There was a higher tendency of infections in the study group (P = .059). Higher organ failure scores and prolonged stay in ICU predicted worse outcome (P < .05). Conclusion. The frequency of complications in patients with NCSE who are cared for in the ICU is considerable. Most of the complications are similar to the other patients in ICU, except for the higher frequency of infections. Increased physician awareness about modifiable parameters and timely interventions might help improve prognosis.

Seizure Management in the Intensive Care Unit

Purpose of this review

This review presents current therapy for seizures in the intensive care unit. The reader is provided with recent evidence regarding the use of EEG in determining treatment for acute seizures. Proposed treatment approaches for seizures and status epilepticus are provided. Controversies and complexity of selecting treatments are discussed.

Recent findings

Critical Care EEG Monitoring Research Consortium analyzed the association of periodic and rhythmic electroencephalographic patterns with seizures and found that lateralized and generalized periodic discharges and lateralized rhythmic delta were associated with increased seizure risk. Applications using modified EEG techniques have demonstrated more rapid feedback to the ICU than was previously possible.

Summary

Accurate diagnosis and efficient treatment of seizures in the ICU is challenging due to patient factors, complexities of antiepileptic drug therapy, and the required expertise for EEG interpretation. Selection of optimally effective therapy for seizures or status epilepticus depends on multiple factors, making collaboration between neurophysiologists and the ICU team of paramount importance.

Diagnosis and Management of Status Epilepticus

Seizures are among the most common neurological presentations to the emergency room. They present on a spectrum of severity from isolated new-onset seizures to acute repetitive seizures and, in severe cases, status epilepticus. The latter is the most serious, as it is associated with high morbidity and mortality. Prompt recognition and treatment of both seizure activity and associated acute systemic complications are essential to improve the overall outcome of these patients. The purpose of this review is to provide the current viewpoint on the diagnostic evaluation and pharmacological management of patients presenting with status epilepticus, and the common associated systemic complications.

Review and Updates on the Treatment of Refractory and Super Refractory Status Epilepticus

Refractory and super-refractory status epilepticus (RSE and SRSE) are life-threatening conditions requiring prompt initiation of appropriate treatment to avoid permanent neurological damage and reduce morbidity and mortality. RSE is defined as status epilepticus that persists despite administering at least two appropriately dosed parenteral medications, including a benzodiazepine. SRSE is status epilepticus that persists at least 24 h after adding at least one appropriately dosed continuous anesthetic (i.e., midazolam, propofol, pentobarbital, and ketamine). Other therapeutic interventions include immunotherapy, neuromodulation, ketogenic diet, or even surgical intervention in certain cases. Continuous electroencephalogram is an essential monitoring tool for diagnosis and treatment. In this review, we focus on the diagnosis and treatment of RSE and SRSE.

Evaluation and Management of Seizures and Status Epilepticus

Seizures are frequently triggered by an inciting event and result from uninhibited excitation and/or decreased inhibition of a pool of neurons. If physiologic seizure abortive mechanisms fail, the ensuing unrestrained synchronization of neurons-status epilepticus-can be life-threatening and is associated with the potential for marked morbidity in survivors and high medical care costs. Prognosis is intimately related to etiology and its response to therapeutic measures. Timely implementation of pharmacologic therapy while concurrently performing a stepwise workup for etiology are paramount. Neurodiagnostic testing should guide titration of pharmacologic therapies, and help determine if there is a role for immune modulation.

Pharmacotherapy for Nonconvulsive Seizures and Nonconvulsive Status Epilepticus

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

[S2k guidelines: status epilepticus in adulthood : Guidelines of the German Society for Neurology]

This S2k guideline on diagnosis and treatment of status epilepticus (SE) in adults is based on the last published version from 2021. New definitions and evidence were included in the guideline and the clinical pathway. A seizures lasting longer than 5 minutes (or ≥ 2 seizures over more than 5 mins without intermittend recovery to the preictal neurological state. Initial diagnosis should include a cCT or, if possible, an MRI. The EEG is highly relevant for diagnosis and treatment-monitoring of non-convulsive SE and for the exclusion or diagnosis of psychogenic non-epileptic seizures. As the increasing evidence supports the relevance of inflammatory comorbidities (e.g. pneumonia) related clinical chemistry should be obtained and repeated over the course of a SE treatment, and antibiotic therapy initiated if indicated.Treatment is applied on four levels: 1. Initial SE: An adequate dose of benzodiazepine is given i.v., i.m., or i.n.; 2. Benzodiazepine-refractory SE: I.v. drugs of 1st choice are levetiracetam or valproate; 3. Refractory SE (RSE) or 4. Super-refractory SE (SRSE): I.v. propofol or midazolam alone or in combination or thiopental in anaesthetic doses are given. In focal non-convulsive RSE the induction of a therapeutic coma depends on the circumstances and is not mandatory. In SRSE the ketogenic diet should be given. I.v. ketamine or inhalative isoflorane can be considered. In selected cased electroconvulsive therapy or, if a resectable epileptogenic zone can be defined epilepsy surgery can be applied. I.v. allopregnanolone or systemic hypothermia should not be used.

A Theoretical Paradigm for Evaluating Risk-Benefit of Status Epilepticus Treatment

Aggressive treatment of status epilepticus with anesthetic drugs can provide rapid seizure control, but it might lead to serious medical complications and worse outcomes. Using a decision analysis approach, this concise review provides a framework for individualized decision making about aggressive and nonaggressive treatment in status epilepticus. The authors propose and review the most relevant parameters guiding the risk-benefit analysis of treatment aggressiveness in status epilepticus and present real-world-based case examples to illustrate how these tools could be used at the bedside and serve to guide future research in refractory status epilepticus treatment.

Long-term prognosis related to deep sedation in refractory status Epilepticus

OBJECTIVE

To evaluate long-term prognosis in patients with refractory status epilepticus according to the level of sedation reached during drug-induced coma.

MATERIALS AND METHODS

Longitudinal study of patients with status epilepticus who received anesthetics to induce therapeutic coma. Demographic data, clinical, and electroencephalographic characteristics were collected, as well as variables related to sedation. We considered as deep sedation the EEG burst-suppression patterns (suppression ratio > 50%). A GOSE (Glasgow Outcome Scale Extended) score of 7 or 8 was considered as good prognosis. A comparative study was carried out to identify predictors of good or poor prognosis at discharge, at 1 and 2 years of follow-up.

RESULTS

We included 61 patients: 63.9% were men; mean age 53.5 ± 16.8 years (range 16-86 years), 39.3% reached deep sedation; 62.3% had > 48 h induced coma. The median hospital stay was 21 days, while 10 days in the intensive care unit (ICU). In the multiple regression analysis, an ICU length of stay ≥ 7 days was associated with poor prognosis at discharge and at long-term (P < .05), while deep sedation was associated only with poor long-term prognosis (1 and 2 years, P < .05). The Kaplan-Meier curve showed higher survival in the group that did not undergo deep sedation (P < .05).

CONCLUSIONS

In refractory status epilepticus, deep sedation is associated with poor prognosis at long-term.

Electroencephalogram Monitoring in Critical Care

Seizures are common in critically ill patients. Electroencephalogram (EEG) is a tool that enables clinicians to provide continuous brain monitoring and to guide treatment decisions-brain telemetry. EEG monitoring has particular utility in the intensive care unit as most seizures in this setting are nonconvulsive. Despite the increased use of EEG monitoring in the critical care unit, it remains underutilized. In this review, we summarize the utility of EEG and different EEG modalities to monitor patients in the critical care setting.

Drug Trials in Status Epilepticus: Current Evidence and Future Concepts

Status epilepticus (SE) is a neurologic emergency with high morbidity and mortality. After many advances in the field, several unanswered questions remain for optimal treatment after the early stage of SE. This narrative review describes some of the important drug trials for SE treatment that have shaped the understanding of the treatment of SE. The authors also propose possible clinical trial designs for the later stages of SE that may allow assessment of currently available and new treatment options. Status epilepticus can be divided into four stages for treatment purposes: early, established, refractory, and superrefractory. Ongoing convulsive seizures for more than 5 minutes or nonconvulsive seizure activity for more than 10 to 30 minutes is considered early SE. Failure to control the seizure with first-line treatment (usually benzodiazepines) is defined as established SE. If SE continues despite treatment with an antiseizure medicine, it is considered refractory SE, which is usually treated with additional antiseizure medicines or intravenous anesthetic agents. Continued seizures for more than 24 hours despite use of intravenous anesthetic agents is termed superrefractory SE. Evidence-based treatment recommendations from high-quality clinical trials are available for only the early stages of SE. Among the challenges for designing a treatment trial for the later stages SE is the heterogeneity of semiology, etiology, age groups, and EEG correlates. In many instances, SE is nonconvulsive in later stages and diagnosis is possible only with EEG. EEG patterns can be challenging to interpret and only recently have consensus criteria for EEG diagnosis of SE emerged. Despite having these EEG criteria, interrater agreement in EEG interpretation can be challenging. Defining successful treatment can also be difficult. Finally, the ethics of randomizing treatment and possibly using a placebo in critically ill patients must also be considered. Despite these challenges, clinical trials can be designed that navigate these issues and provide useful answers for how best to treat SE at various stages.

Treatment of Refractory Convulsive Status Epilepticus: A Comprehensive Review by the American Epilepsy Society Treatments Committee

Purpose:

Established tonic–clonic status epilepticus (SE) does not stop in one-third of patients when treated with an intravenous (IV) benzodiazepine bolus followed by a loading dose of a second antiseizure medication (ASM). These patients have refractory status epilepticus (RSE) and a high risk of morbidity and death. For patients with convulsive refractory status epilepticus (CRSE), we sought to determine the strength of evidence for 8 parenteral ASMs used as third-line treatment in stopping clinical CRSE.

Methods:

A structured literature search (MEDLINE, Embase, CENTRAL, CINAHL) was performed to identify original studies on the treatment of CRSE in children and adults using IV brivaracetam, ketamine, lacosamide, levetiracetam (LEV), midazolam (MDZ), pentobarbital (PTB; and thiopental), propofol (PRO), and valproic acid (VPA). Adrenocorticotropic hormone (ACTH), corticosteroids, intravenous immunoglobulin (IVIg), magnesium sulfate, and pyridoxine were added to determine the effectiveness in treating hard-to-control seizures in special circumstances. Studies were evaluated by predefined criteria and were classified by strength of evidence in stopping clinical CRSE (either as the last ASM added or compared to another ASM) according to the 2017 American Academy of Neurology process.

Results:

No studies exist on the use of ACTH, corticosteroids, or IVIg for the treatment of CRSE. Small series and case reports exist on the use of these agents in the treatment of RSE of suspected immune etiology, severe epileptic encephalopathies, and rare epilepsy syndromes. For adults with CRSE, insufficient evidence exists on the effectiveness of brivaracetam (level U; 4 class IV studies). For children and adults with CRSE, insufficient evidence exists on the effectiveness of ketamine (level U; 25 class IV studies). For children and adults with CRSE, it is possible that lacosamide is effective at stopping RSE (level C; 2 class III, 14 class IV studies). For children with CRSE, insufficient evidence exists that LEV and VPA are equally effective (level U, 1 class III study). For adults with CRSE, insufficient evidence exists to support the effectiveness of LEV (level U; 2 class IV studies). Magnesium sulfate may be effective in the treatment of eclampsia, but there are only case reports of its use for CRSE. For children with CRSE, insufficient evidence exists to support either that MDZ and diazepam infusions are equally effective (level U; 1 class III study) or that MDZ infusion and PTB are equally effective (level U; 1 class III study). For adults with CRSE, insufficient evidence exists to support either that MDZ infusion and PRO are equally effective (level U; 1 class III study) or that low-dose and high-dose MDZ infusions are equally effective (level U; 1 class III study). For children and adults with CRSE, insufficient evidence exists to support that MDZ is effective as the last drug added (level U; 29 class IV studies). For adults with CRSE, insufficient evidence exists to support that PTB and PRO are equally effective (level U; 1 class III study). For adults and children with CRSE, insufficient evidence exists to support that PTB is effective as the last ASM added (level U; 42 class IV studies). For CRSE, insufficient evidence exists to support that PRO is effective as the last ASM used (level U; 26 class IV studies). No pediatric-only studies exist on the use of PRO for CRSE, and many guidelines do not recommend its use in children aged <16 years. Pyridoxine-dependent and pyridoxine-responsive epilepsies should be considered in children presenting between birth and age 3 years with refractory seizures and no imaging lesion or other acquired cause of seizures. For children with CRSE, insufficient evidence exists that VPA and diazepam infusion are equally effective (level U, 1 class III study). No class I to III studies have been reported in adults treated with VPA for CRSE. In comparison, for children and adults with established convulsive SE (ie, not RSE), after an initial benzodiazepine, it is likely that loading doses of LEV 60 mg/kg, VPA 40 mg/kg, and fosphenytoin 20 mg PE/kg are equally effective at stopping SE (level B, 1 class I study).

Conclusions:

Mostly insufficient evidence exists on the efficacy of stopping clinical CRSE using brivaracetam, lacosamide, LEV, valproate, ketamine, MDZ, PTB, and PRO either as the last ASM or compared to others of these drugs. Adrenocorticotropic hormone, IVIg, corticosteroids, magnesium sulfate, and pyridoxine have been used in special situations but have not been studied for CRSE. For the treatment of established convulsive SE (ie, not RSE), LEV, VPA, and fosphenytoin are likely equally effective, but whether this is also true for CRSE is unknown. Triple-masked, randomized controlled trials are needed to compare the effectiveness of parenteral anesthetizing and nonanesthetizing ASMs in the treatment of CRSE.

Status epilepticus - time is brain and treatment considerations

PURPOSE OF REVIEW

Status epilepticus is a neurological emergency associated with high morbidity and mortality. There is a lack of robust data to guide the management of this neurological emergency beyond the initial treatment. This review examines recent literature on treatment considerations including the choice of continuous anesthetics or adjunctive anticonvulsant, the cause of the status epilepticus, and use of nonpharmacologic therapies.

RECENT FINDINGS

Status epilepticus remains undertreated and mortality persists to be unchanged over the past 30 years. New anticonvulsant choices, such as levetiracetam and lacosamide have been explored as alternative emergent therapies. Anecdotal reports on the use of other generation anticonvulsants and nonpharmacologic therapies for the treatment of refractory and super-refractory status epilepticus have been described.Finally, recent evidence has examined etiology-guided management of status epilepticus in certain patient populations, such as immune-mediated, paraneoplastic or infectious encephalitis and anoxic brain injury.

SUMMARY

Randomized clinical trials are needed to determine the role for newer generation anticonvulsants and nonpharmacologic modalities for the treatment of epilepticus remains and evaluate the long-term outcomes associated with continuous anesthetics.

Association between incident delirium and 28- and 90-day mortality in critically ill adults: a secondary analysis

BACKGROUND

While delirium prevalence and duration are each associated with increased 30-day, 6-month, and 1-year mortality, the association between incident ICU delirium and mortality remains unclear. We evaluated the association between both incident ICU delirium and days spent with delirium in the 28 days after ICU admission and mortality within 28 and 90 days.

METHODS

Secondary cohort analysis of a randomized, double-blind, placebo-controlled trial conducted among 1495 delirium-free, critically ill adults in 14 Dutch ICUs with an expected ICU stay ≥2 days where all delirium assessments were completed. In the 28 days after ICU admission, patients were evaluated for delirium and coma 3x daily; each day was coded as a delirium day [≥1 positive Confusion Assessment Method for the ICU (CAM-ICU)], a coma day [no delirium and ≥ 1 Richmond Agitation Sedation Scale (RASS) score ≤ - 4], or neither. Four Cox-regression models were constructed for 28-day mortality and 90-day mortality; each accounted for potential confounders (i.e., age, APACHE-II score, sepsis, use of mechanical ventilation, ICU length of stay, and haloperidol dose) and: 1) delirium occurrence, 2) days spent with delirium, 3) days spent in coma, and 4) days spent with delirium and/or coma.

RESULTS

Among the 1495 patients, 28 day mortality was 17% and 90 day mortality was 21%. Neither incident delirium (28 day mortality hazard ratio [HR] = 1.02, 95%CI = 0.75-1.39; 90 day mortality HR = 1.05, 95%CI = 0.79-1.38) nor days spent with delirium (28 day mortality HR = 1.00, 95%CI = 0.95-1.05; 90 day mortality HR = 1.02, 95%CI = 0.98-1.07) were significantly associated with mortality. However, both days spent with coma (28 day mortality HR = 1.05, 95%CI = 1.02-1.08; 90 day mortality HR = 1.05, 95%CI = 1.02-1.08) and days spent with delirium or coma (28 day mortality HR = 1.03, 95%CI = 1.00-1.05; 90 day mortality HR = 1.03, 95%CI = 1.01-1.06) were significantly associated with mortality.

CONCLUSIONS

This analysis suggests neither incident delirium nor days spent with delirium are associated with short-term mortality after ICU admission.

TRIAL REGISTRATION

ClinicalTrials.gov, Identifier NCT01785290 Registered 7 February 2013.

Electrographic predictors of successful weaning from anaesthetics in refractory status epilepticus

Intravenous third-line anaesthetic agents are typically titrated in refractory status epilepticus to achieve either seizure suppression or burst suppression on continuous EEG. However, the optimum treatment paradigm is unknown and little data exist to guide the withdrawal of anaesthetics in refractory status epilepticus. Premature withdrawal of anaesthetics risks the recurrence of seizures, whereas the prolonged use of anaesthetics increases the risk of treatment-associated adverse effects. This study sought to measure the accuracy of features of EEG activity during anaesthetic weaning in refractory status epilepticus as predictors of successful weaning from intravenous anaesthetics. We prespecified a successful anaesthetic wean as the discontinuation of intravenous anaesthesia without developing recurrent status epilepticus, and a wean failure as either recurrent status epilepticus or the resumption of anaesthesia for the purpose of treating an EEG pattern concerning for incipient status epilepticus. We evaluated two types of features as predictors of successful weaning: spectral components of the EEG signal, and spatial-correlation-based measures of functional connectivity. The results of these analyses were used to train a classifier to predict wean outcome. Forty-seven consecutive anaesthetic weans (23 successes, 24 failures) were identified from a single-centre cohort of patients admitted with refractory status epilepticus from 2016 to 2019. Spectral components of the EEG revealed no significant differences between successful and unsuccessful weans. Analysis of functional connectivity measures revealed that successful anaesthetic weans were characterized by the emergence of larger, more densely connected, and more highly clustered spatial functional networks, yielding 75.5% (95% confidence interval: 73.1-77.8%) testing accuracy in a bootstrap analysis using a hold-out sample of 20% of data for testing and 74.6% (95% confidence interval 73.2-75.9%) testing accuracy in a secondary external validation cohort, with an area under the curve of 83.3%. Distinct signatures in the spatial networks of functional connectivity emerge during successful anaesthetic liberation in status epilepticus; these findings are absent in patients with anaesthetic wean failure. Identifying features that emerge during successful anaesthetic weaning may allow faster and more successful anaesthetic liberation after refractory status epilepticus.