Nonconvulsive status epilepticus in adults - insights into the invisible

Status epilepticus and psychosis: Lessons from SEEG

Psychotic manifestations are a classic feature of non-convulsive status epilepticus (NCSE) of temporal origin. For several decades now, the various psychiatric manifestations of NCSE have been described, and in particular, the diagnostic challenges they pose. However, studies using stereotactic-EEG (SEEG) recordings are very rare. Only a few cases have been reported, but they demonstrated the anatomical substrate of certain manifestations, including hallucinations, delusions, and emotional changes. The post-ictal origin of some of the manifestations should be emphasized. More generally, SEEG has shown that seizures affecting the temporal and frontal limbic systems can lead to intense emotional experiences and behavioural disturbances.

Association Between Dose Escalation of Anesthetics and Outcomes in Patients With Refractory Status Epilepticus

BACKGROUND AND OBJECTIVES

To investigate the association between dose escalation of continuously administered IV anesthetics and its duration with short-term outcomes in adult patients treated for refractory status epilepticus (RSE).

METHODS

Clinical and electroencephalographic data of patients with RSE without hypoxic-ischemic encephalopathy who were treated with anesthetics at a Swiss academic medical center from 2011 to 2019 were assessed. The frequency of anesthetic dose escalation (i.e., dose increase) and its associations with in-hospital death or return to premorbid neurologic function were primary endpoints. Multivariable logistic regression analysis was performed to identify associations with endpoints.

RESULTS

Among 111 patients with RSE, doses of anesthetics were escalated in 57%. Despite patients with dose escalation having a higher morbidity (lower Glasgow Coma Scale [GCS] score at status epilepticus [SE] onset, more presumably fatal etiologies, longer duration of SE and intensive care, more infections, and arterial hypotension) as compared with patients without, the primary endpoints did not differ between these groups in univariable analyses. Multivariable analyses revealed decreased odds for death with dose escalation (odds ratio 0.09, 95% CI 0.01-0.86), independent of initial GCS score, presumably fatal etiology, SE severity score, SE duration, and nonconvulsive SE with coma, with similar functional outcome among survivors compared with patients without dose escalation.

DISCUSSION

Our study reveals that anesthetic dose escalation in adult patients with RSE is associated with decreased odds for death without increasing the proportion of surviving patients with worse neurofunctional state than before RSE.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that anesthetic dose escalation decreases the odds of death in patients with RSE.

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.

Delayed Diagnosis of an Invisible Seizure: Cefepime-Induced Non-convulsive Status Epilepticus

Cefepime-induced non-convulsive status epilepticus (NCSE) is a recognized adverse event of cefepime. Risk factors for this adverse event include older age, underlying renal dysfunction, previous brain injury, diabetes, and severe infection. We present a case of a 79-year-old woman with no prior seizure history, who was admitted for Pseudomonas aeruginosa surgical wound infection for which she was on cefepime. She developed acute encephalopathy with associated, occasional, right-sided myoclonic facial twitches 11 days into her admission. Electroencephalogram (EEG) confirmed NCSE as evident by epileptiform activity described as generalized periodic discharges with predominantly triphasic morphology. Cefepime was substituted with piperacillin-tazobactam> 24 hours after symptom onset. NCSE completely resolved two days after the discontinuation of cefepime. This case highlights the fact that NCSE can occur even when precautions such as renal dosing of cefepime are observed. Clinicians need to have a high index of suspicion for the condition when taking care of at-risk patients on cefepime, as delayed diagnosis correlates with potentially fatal outcomes.

Neurological adverse effects of chimeric antigen receptor T-cell therapy

INTRODUCTION

Chimeric antigen receptor (CAR) T-cell is among the most prevalent approaches that act by directing T-cells toward cancer; however, they need to be optimized to minimize side effects and maximize efficacy before being used as standard treatment for malignancies. Neurotoxicity associated with CAR T-cell therapy has been well-documented in recent works.

AREAS COVERED

In this regard, two established syndromes exist. Immune effector cell-associated neurotoxicity syndrome (ICANS), previously called cytokine release encephalopathy syndrome (CRES), is a neuropsychiatric condition which can occur after therapy by immune effector cells (IEC) and T-lymphocytes utilizing treatments. Another syndrome is cytokine release syndrome (CRS), which may overlap with ICANS.

EXPERT OPINION

ICANS clinical manifestations include cerebral edema, mild lethargy, aphasia, and seizures. Notably, ICANS is associated with changes to EEG and neuroradiological findings. Therefore, it is necessary to make a timely and accurate diagnosis of neurological complications of CAR T-cells by clinical presentations, neuroimaging, and EEG. Since neurological events by different CAR T-cell products are heterogeneous, guides should be developed according to each product. Here, we provide an updated review of general information on CAR T-cell therapies and applications, neurological syndromes associated with their use, and risk factors contributing to ICANS.

Nonconvulsive Status Epilepticus Associated with Cerebral Hyperperfusion Syndrome after Carotid Endarterectomy: A Case Report

We report a case of a 73-year-old man who developed nonconvulsive status epilepticus as a complication of cerebral hyperperfusion syndrome after carotid endarterectomy for carotid artery stenosis. On postoperative day 1, the patient experienced headaches and vomiting. Resting N-isopropyl-p-[¹²³I] iodoamphetamine single-photon emission computed tomography showed increased cerebral blood flow to the entire right hemisphere, and the patient was diagnosed with cerebral hyperperfusion syndrome. He was treated with antihypertensive and antiseizure medications, sedated using propofol, intubated, and placed under mechanical ventilation. On postoperative day 3, computed tomography perfusion imaging showed a reduction in hyperperfusion, and propofol sedation was terminated on postoperative day 4. However, the patient exhibited prolonged impaired awareness and roving eye movements, and long-term video electroencephalographic monitoring revealed electrographic seizures. The patient was diagnosed with nonconvulsive status epilepticus. Propofol sedation was resumed, and the antiseizure medication dose was increased. Subsequently, the state of hyperperfusion in the right hemisphere diminished, and electroencephalographic findings improved, allowing sedation to be terminated on postoperative day 7. The findings from this case suggest that when clinical subtle symptoms, such as impaired awareness and roving eye movements, are observed during treatment of cerebral hyperperfusion syndrome, video electroencephalography should be performed to detect electrographic seizures.

Early timing of anesthesia in status epilepticus is associated with complete recovery: A 7-year retrospective two-center study

OBJECTIVE

This study was undertaken to investigate the efficacy, tolerability, and outcome of different timing of anesthesia in adult patients with status epilepticus (SE).

METHODS

Patients with anesthesia for SE from 2015 to 2021 at two Swiss academic medical centers were categorized as anesthetized as recommended third-line treatment, earlier (as first- or second-line treatment), and delayed (later as third-line treatment). Associations between timing of anesthesia and in-hospital outcomes were estimated by logistic regression.

RESULTS

Of 762 patients, 246 received anesthesia; 21% were anesthetized as recommended, 55% earlier, and 24% delayed. Propofol was preferably used for earlier (86% vs. 55.5% for recommended/delayed anesthesia) and midazolam for later anesthesia (17.2% vs. 15.9% for earlier anesthesia). Earlier anesthesia was statistically significantly associated with fewer infections (17% vs. 32.7%), shorter median SE duration (.5 vs. 1.5 days), and more returns to premorbid neurologic function (52.9% vs. 35.5%). Multivariable analyses revealed decreasing odds for return to premorbid function with every additional nonanesthetic antiseizure medication given prior to anesthesia (odds ratio [OR] = .71, 95% confidence interval [CI] = .53-.94) independent of confounders. Subgroup analyses revealed decreased odds for return to premorbid function with increasing delay of anesthesia independent of the Status Epilepticus Severity Score (STESS; STESS = 1-2: OR = .45, 95% CI = .27-.74; STESS > 2: OR = .53, 95% CI = .34-.85), especially in patients without potentially fatal etiology (OR = .5, 95% CI = .35-.73) and in patients experiencing motor symptoms (OR = .67, 95% CI = .48-.93).

SIGNIFICANCE

In this SE cohort, anesthetics were administered as recommended third-line therapy in only every fifth patient and earlier in every second. Increasing delay of anesthesia was associated with decreased odds for return to premorbid function, especially in patients with motor symptoms and no potentially fatal etiology.

Association Between Induced Burst Suppression and Clinical Outcomes in Patients With Refractory Status Epilepticus: A 9-Year Cohort Study

BACKGROUND AND OBJECTIVES

To investigate the frequency of induced EEG burst suppression pattern during continuous IV anesthesia (IVAD) and associated outcomes in adult patients treated for refractory status epilepticus (RSE).

METHODS

Patients with RSE treated with anesthetics at a Swiss academic care center from 2011 to 2019 were included. Clinical data and semiquantitative EEG analyses were assessed. Burst suppression was categorized as incomplete burst suppression (with ≥20% and <50% suppression proportion) or complete burst suppression (with ≥50% suppression proportion). The frequency of induced burst suppression and association of burst suppression with outcomes (persistent seizure termination, in-hospital survival, and return to premorbid neurologic function) were the endpoints.

RESULTS

We identified 147 patients with RSE treated with IVAD. Among 102 patients without cerebral anoxia, incomplete burst suppression was achieved in 14 (14%) with a median of 23 hours (interquartile range [IQR] 1-29) and complete burst suppression was achieved in 21 (21%) with a median of 51 hours (IQR 16-104). Age, Charlson comorbidity index, RSE with motor symptoms, the Status Epilepticus Severity Score and arterial hypotension requiring vasopressors were identified as potential confounders in univariable comparisons between patients with and without any burst suppression. Multivariable analyses revealed no associations between any burst suppression and the predefined endpoints. However, among 45 patients with cerebral anoxia, induced burst suppression was associated with persistent seizure termination (72% without vs 29% with burst suppression, p = 0.004) and survival (50% vs 14% p = 0.005).

DISCUSSION

In adult patients with RSE treated with IVAD, burst suppression with ≥50% suppression proportion was achieved in every fifth patient and not associated with persistent seizure termination, in-hospital survival, or return to premorbid neurologic function.

Comparing Patients With Isolated Seizures and Status Epilepticus in Intensive Care Units: An Observational Cohort Study

BACKGROUND AND OBJECTIVES

To assess the frequency of status epilepticus (SE) among seizing critically ill adult patients and to determine clinical differences between patients with isolated seizures and patients with SE in the intensive care unit (ICU).

METHODS

From 2015 to 2020, all consecutive adult ICU patients at a Swiss tertiary care center with isolated seizures or SE as reported by intensivists and/or consulting neurologists were identified by screening of all digital medical, ICU, and EEG records. Patients aged <18 years and patients with myoclonus due to hypoxic-ischemic encephalopathy but without seizures on EEG were excluded. The frequency of isolated seizures, SE, and clinical characteristics at seizure onset associated with SE were the primary outcomes. Uni- and multivariable logistic regression was performed to identify associations with the emergence of SE.

RESULTS

Among 404 patients with seizures, 51% had SE. Compared with patients with isolated seizures, patients with SE had a lower median Charlson Comorbidity Index (CCI) (3 vs 5, p < 0.001), fewer fatal etiologies (43.6% vs 80.5%, p < 0.001), higher median Glasgow coma scores (7 vs 5, p < 0.001), fever more frequently (27.5% vs 7.5%, p < 0.001), shorter median ICU and hospital stay (ICU: 4 vs 5 days, p = 0.039; hospital stay: 13 vs 15 days, p = 0.045), and recovered to premorbid function more often (36.8% vs 17%, p < 0.001). Multivariable analyses revealed decreased odds ratios (ORs) for SE with increasing CCI (OR 0.91, 95% CI 0.83-0.99), fatal etiology (OR 0.15, 95% CI 0.08-0.29), and epilepsy (OR 0.32, 95% CI 0.16-0.63). Systemic inflammation was an additional association with SE after excluding patients with seizures as the reason for ICU admission (ORfor CRP 1.01, 95% CI 1.00-1.01; ORfor fever 7.35, 95% CI 2.84-19.0). Although fatal etiologies and increasing CCI remained associated with low odds for SE after excluding anesthetized patients and hypoxic-ischemic encephalopathy, inflammation remained associated in all subgroups except patients with epilepsy.

DISCUSSION

Among all ICU patients with seizures, SE emerged frequently and seen in every second patient. Besides the unexpected low odds for SE with higher CCI, fatal etiology, and epilepsy, the association of inflammation with SE in the critically ill without epilepsy represents a potential treatment target and deserves further attention.

Prevalence, electroclinical spectrum and effect on the outcome of non-convulsive status epilepticus in critically ill patients; the utility of routine electroencephalogram

OBJECTIVES

To highlight the importance of routine electroencephalogram (rEEG) in detecting non-convulsive status epilepticus (NCSE), describing the electroclinical spectrum and effect on outcome in critically ill patients with altered mental status (CIPAMS).

METHODS

This retrospective study was conducted at King Fahd University Hospital. Clinical data and EEG recordings of CIPAMS to rule out NCSE were reviewed. All patients had at least 30 minutes of EEG recording. The Salzburg Consensus criteria (SCC) were applied to diagnose NCSE. The data analysis was performed using SPSS version 22.0. The chi-squared test was used to compare categorical variables such as etiologies, EEG findings, and functional outcomes. Multivariable analysis was performed to identify the predictors of unfavorable outcomes.

RESULTS

A total of 323 CIPAMS referred to rule out NCSE were enrolled (mean age 57.8 ± 20 years). Nonconvulsive status epilepticus was diagnosed in 54 (16.7%) patients. A significant association was found between subtle clinical features and NCSE (P =< 0.01). Acute ischemic stroke (18.5%), sepsis (18.5%), and hypoxic brain injury (22.2%) were the main etiologies. The previous history of epilepsy was significantly associated with NCSE (P = 0.01). Acute stroke, cardiac arrest, mechanical ventilation, and NCSE were statistically associated with unfavorable outcomes. Nonconvulsive status epilepticus was an independent predictor of unfavorable outcomes (P = 0.02, OR = 2.75, CI = 1.16-6.48) during multivariable analysis. Sepsis was associated with higher mortality (P =< 0.01, OR = 2.4, CI = 1.4-4.0).

SIGNIFICANCE

Our study findings suggest that the utility of rEEG in detecting NCSE in CIPAMS should not be underestimated. Important observations further indicate that repeating rEEG is advisable, as this would increase the likelihood of identifying NCSE. Thus, physicians should consider and repeat rEEG when evaluating CIPAMS in order to detect NCSE, which is an independent predictor of unfavorable outcomes. Nonetheless, further studies comparing rEEG and cEEG yields are required to augment the current understanding of the electroclinical spectrum and better describe NCSE in CIPAMS.

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.

Balancing the risks and benefits of anesthetics in status epilepticus

PURPOSE

According to international guidelines, status epilepticus refractory to first- and second-line antiseizure medication should be treated with anesthetics. Therefore, continuously delivered intravenous midazolam, propofol, or barbiturates are recommended as third-line therapy. While electroencephalographically (EEG)-controlled titration of anesthetics to seizure termination or to the emergence of an EEG burst-suppression pattern makes sense, evidence of the efficacy and tolerability of such third-line treatment is limited and concerns regarding the risks of anesthesia remain. The lack of treatment alternatives and persistent international discord reflecting contradictory results from some studies leave clinicians on their own when deciding to escalate treatment. In this conference-accompanying narrative review, we highlight the challenges of EEG-monitored third-line treatment and discuss recent studies that examined earlier administration of anesthetics.

RESULTS

Based on the literature, maintaining continuous burst suppression is difficult despite the constant administration of anesthetics, and the evidence for burst suppression as an adequate surrogate target is limited by methodological shortcomings as acknowledged by international guidelines. In our Swiss cohort including 102 patients with refractory status epilepticus, burst suppression as defined by the American Clinical Neurophysiology Society's Critical Care EEG Terminology 2021 was established in only 21%. Besides case reports suggesting that rapid but short-termed anesthesia can be sufficient to permanently stop seizures, a study including 205 patients revealed that anesthesia as second-line treatment was associated with a shorter median duration of status epilepticus (0.5 versus 12.5 days, p < 0.001), median ICU (2 versus 5.5 days, p < 0.001) and hospital stay (8 versus 17 days, p < 0.001) with equal rates of complications when compared to anesthesia as third-line treatment.

CONCLUSIONS

Recent investigations have led to important findings and new insights regarding the use of anesthetics in refractory status epilepticus. However, numerous methodological limitations and remaining questions need to be considered when it comes to the translation into clinical practice, and, in consequence, call for prospective randomized studies. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.

Power spectrum analysis and outcomes of non-convulsive status epilepticus: a single-center study

OBJECTIVES

Diagnosis of non-convulsive status epilepticus (NCSE) is challenging and outcomes during follow-up are not clear. This study aimed to conduct power spectrum analysis in NCSE and measure outcomes of patients.

METHODS

We searched continuous EEG monitoring (cEEG) recordings to identify patients of NCSE. An artifact-free cEEG epoch of continuous 60 s was chosen for spectral power analysis. We also collected electronic medical records of the patients for extracting clinical information. Patients recruited were followed up at least every half a year.

RESULTS

There were 48 patients with 64 independent NCSE episodes during different course of disease recruited in the study, with a mean age of 40.3 ± 19.1 years (range, 12-72 years), including 24 males (50%) and 24 females (50%). When the spectral power of 60 s equaled to 11.30 μV² for predicting impairment of consciousness, (sensitivity, specificity) = (0.979, 0.625). When the spectral power of 60 s equaled to 52.70 μV² for predicting myoclonic jerks, (sensitivity, specificity) = (0.783, 0.756). There were 27 patients (56.3%) followed up with a duration over 12 months. Nineteen patients (70.4%) continued to have seizures. Eleven (40.7%) resisted to at least two kinds of appropriate anti-seizure medication at maximum tolerated levels. Five patients with prolonged NCSE suffered from loss of brain parenchymal volume on follow-up MRI scans.

CONCLUSION

Spectral power analysis can be used to detect mental status and limb jerks. Early diagnosis and treatment of NCSE are important, which can influence outcomes of the patients during follow-up.

Nonconvulsive status epilepticus following cardiac arrest: overlooked, untreated and misjudged

AIMS

Seizures and status epilepticus (SE) are detected in almost a third of the comatose cardiac arrest survivors. As the literature is quite exhaustive regarding SE with motor symptoms in those patients, little is known about nonconvulsive SE (NCSE). Our aim was to compile the evidence from the literature of the frequency and outcome of NCSE in adult patients remaining in coma after resuscitation.

METHODS

The medical search PubMed was screened for most relevant articles reporting the emergence and outcome of NCSE in comatose post-resuscitated adult patients.

RESULTS

We identified 11 cohort studies (four prospective observational, seven retrospective) including 1092 patients with SE in 29-96% and NCSE reported in 1-20%. EEG evaluation started at a median of 9.5 h (range 7.5-14.8) after cardiac arrest, during sedation and targeted temperature management (TTM). Favorable outcome after NCSE occurred in 24.5%. We found no study reporting EEG to detect or exclude NCSE in patients remaining in coma prior to the initiation of TTM and without sedation withing the first hours after ROSC.

DISCUSSION

Studies on NCSE after ROSC are scarce and unsystematic, reporting favorable outcome in every fourth patient experiencing NCSE after ROSC. This suggests that NCSE is often overlooked and outcome after NCSE is not always poor. The low data quality does not allow firm conclusions regarding the effects of NCSE on outcome calling for further investigation. In the meantime, clinicians should avoid equating NCSE after ROSC with poor prognosis.

[A case of Creutzfeldt-Jakob disease presenting with nonconvulsive status epilepticus in the early stages]

A 64-year-old Japanese woman presented with 1 week of recurrent convulsive seizures. At the time of admission, she was in a coma and did not present with convulsions. Intravenous diazepam administration improved her consciousness, although severe psychomotor excitement developed. Brain MRI demonstrated diffusion restriction in the cerebral cortex of the right hemisphere. Electroencephalography (EEG) showed periodic discharges centered around the parietal regions with right-sided dominance. Nonconvulsive status epilepticus (NCSE) was suspected, and the patient was actively treated with anti-epileptic drugs. She developed akinetic mutism and generalized myoclonus 1 month after admission. Follow-up EEG studies disclosed periodic synchronous discharges. Abnormal prion protein in the cerebral fluid was detected using a real-time quaking-induced conversion assay. The clinical diagnosis in the present case was sporadic Creutzfeldt-Jakob disease (CJD). Seizures as an initial symptom in patients with CJD are relatively rare. Our case suggests that CJD should be considered as a differential diagnosis when a patient presents with refractory NCSE.

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.

Prediction of Long-term Survival After Status Epilepticus Using the ACD Score

Importance

Early prediction of long-term mortality in status epilepticus is important given the high fatality rate in the years after diagnosis.

Objective

To improve prognostication of long-term mortality after status epilepticus diagnosis.

Design, Settings, and Participants

This retrospective, multicenter, multinational cohort study analyzed adult patients who were diagnosed with and treated for status epilepticus at university hospitals in Odense, Denmark, between January 1, 2008, and December 31, 2017, as well as in Oslo, Norway; Marburg, Germany; and Frankfurt, Germany. They were aged 18 years or older and had first-time, nonanoxic status epilepticus. A new scoring system, called the ACD score, for predicting 2-year (long-term) mortality after hospital discharge for status epilepticus was developed in the Danish cohort and validated in the German and Norwegian cohorts. The ACD score represents age at onset, level of consciousness at admission, and duration of status epilepticus. Data analysis was performed between September 1, 2019, and March 31, 2020.

Exposures

Long-term follow-up using data from national and local civil registries in Denmark, Norway, and Germany.

Main Outcomes and Measures

The predefined end point was 2-year survival for all patients and for a subgroup of patients with status epilepticus causes that were not damaging or were less damaging to the brain. Neurological deficits before and after onset, demographic characteristics, etiological categories of status epilepticus, comorbidities, survival, time points, treatments, and prognostic scores for different measures were assessed.

Results

A total of 261 patients (mean [SD] age, 67.2 [14.8] years; 132 women [50.6%]) were included, of whom 145 patients (mean [SD] age, 66.3 [15.0] years; 78 women [53.8%]) had status epilepticus causes that were not damaging or were less damaging to the brain. The validation cohort comprised patients from Norway (n = 139) and Germany (n = 906). At hospital discharge, 29.8% of patients (n = 64 of 215) had new moderate to severe neurological deficits compared with baseline. New neurological deficits were a major predictor of 2-year survival after hospital discharge (odds ratio, 5.1; 95% CI, 2.2-11.8); this association was independent of etiological category. Nonconvulsive status epilepticus in coma and duration of status epilepticus were associated with development of new neurological deficits, and a simple 3-factor score (ACD score) combining these 2 risk factors with age at onset was developed to estimate survival after status epilepticus diagnosis. The ACD score had a linear correlation with 2-year survival (Pearson r2 = 0.848), especially in the subset of patients with a low likelihood of brain damage.

Conclusions and Relevance

This study found that age, long duration, and nonconvulsive type of status epilepticus in coma were associated with the development of new neurological deficits, which were predictors of long-term mortality. Accounting for risk factors for new neurological deficits using the ACD score is a reliable method of prediction of long-term outcome in patients with status epilepticus causes that were not damaging or were less damaging to the brain.

Seizures and risks for recurrence in critically ill patients: an observational cohort study

Background

To assess the frequency and clinical characteristics of seizures in adult critically ill patients, to identify predictors of recurrent seizures not transforming into status epilepticus and to characterize their effects on course and outcome.

Methods

ICU patients at a Swiss academic medical center with seizures not transforming into status epilepticus from 2015 to 2020 were included. Recurrent seizures and associated clinical characteristics were primary, death, and return to premorbid neurologic function were secondary outcomes.

Results

Two hundred of 26,370 patients (0.8%) with a median age of 65 years had seizures during ICU stay. Seizure semiology was described in 82% (49% generalized; 33% focal) with impaired consciousness during seizures in 80% and motor symptoms in 62%. Recurrent seizures were reported in 71% (36% on EEG) and associated with longer mechanical ventilation (p = 0.031), higher consultation rate by neurologists (p < 0.001), and increased use of EEG (p < 0.001) when compared to single seizures. The use of EEG was not associated with secondary outcomes. Acidosis at seizure onset and prior emergency operations were associated with decreased odds for seizure recurrence (OR 0.43; 95% CI 0.20–0.94 and OR 0.48; 95% CI 0.24–0.97). Epilepsy had increased odds for seizure recurrence (OR 3.56; 95% CI 1.14–11.16).

Conclusions

Seizures in ICU patients are infrequent, but mostly recurrent, and associated with higher resource utilization. Whenever seizures are observed, clinicians should be vigilant about the increased risk of seizures recurrence and the need for antiseizure treatment must be carefully discussed. While known epilepsy seems to promote recurrent seizures, our results suggest that both acidosis and previous emergency surgery seem to have protective/antiseizure effects.

Trial registration

Clinicaltrials.gov (No. NCT03860467).

COVID-19 masquerading as a non-convulsive status epilepticus

Since the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), more and more atypical presentations of COVID-19 are being reported. Here, we present and discuss non-convulsive status epilepticus (NCSE) as presenting symptom of SARS-CoV-2 infection at the Emergency Department.

First-Response ABCDE Management of Status Epilepticus: A Prospective High-Fidelity Simulation Study

Respiratory infections following status epilepticus (SE) are frequent, and associated with higher mortality, prolonged ICU stay, and higher rates of refractory SE. Lack of airway protection may contribute to respiratory infectious complications. This study investigates the order and frequency of physicians treating a simulated SE following a systematic Airways-Breathing-Circulation-Disability-Exposure (ABCDE) approach, identifies risk factors for non-adherence, and analyzes the compliance of an ABCDE guided approach to SE with current guidelines. We conducted a prospective single-blinded high-fidelity trial at a Swiss academic simulator training center. Physicians of different affiliations were confronted with a simulated SE. Physicians (n = 74) recognized SE and performed a median of four of the five ABCDE checks (interquartile range 3–4). Thereof, 5% performed a complete assessment. Airways were checked within the recommended timeframe in 46%, breathing in 66%, circulation in 92%, and disability in 96%. Head-to-toe (exposure) examination was performed in 15%. Airways were protected in a timely manner in 14%, oxygen supplied in 69%, and antiseizure drugs (ASDs) administered in 99%. Participants’ neurologic affiliation was associated with performance of fewer checks (regression coefficient −0.49; p = 0.015). We conclude that adherence to the ABCDE approach in a simulated SE was infrequent, but, if followed, resulted in adherence to treatment steps and more frequent protection of airways.

Neurology in the psychiatric patient: how to think about differentials in altered mental status and diagnoses not to miss

A wide variety of neurological conditions may present first to a psychiatrist and it is important to be aware of these in differential diagnosis. A careful history, examination and a broad differential diagnosis can help set up an appropriate management plan – with room to change if things change in unexpected ways. In this article we explore common ground shared by psychiatry and neurology and show how incorporation of neurological knowledge can improve the practice of psychiatry. Using four fictional case vignettes of altered mental status we explore important neurological differential diagnoses which could present to the Psychiatrist.

Prolonged mechanical ventilation in patients with terminated status epilepticus and outcome: An observational cohort study

OBJECTIVE

Classical clinical characteristics associated with successful or unsuccessful extubation are unreliable in neurocritically ill patients, and attempts to predict successful extubation in this context have failed. We aimed to investigate the frequency of mechanical ventilation (MV) in adult patients in status epilepticus (SE) and its clinical associations, to identify predictors at SE onset of prolonged postictal MV, and to determine the associated outcomes with prolonged MV.

METHODS

From 2012 to 2018, SE patients treated in intensive care units at a Swiss academic care center were included. Multivariable Poisson regression adjusting for potential confounders, such as continuously administered anesthetics, was performed to identify risks for postictal MV for >24 h after SE and its association with no return to neurologic function and death. Linear regression was performed to identify correlations between the durations of administered specific anesthetics and postictal MV.

RESULTS

Of 262 patients, 42% were ventilated, with 24% being on ventilators for >24 h after SE. Patients with prolonged postictal MV were extubated at a median of 7 days, with 56% not being extubated on the day of successful weaning from MV because of altered consciousness and/or lack of airway-protective reflexes. After extubation, noninvasive ventilation and reintubation were rarely needed. Prolonged postictal MV was associated with increased risk for death independent of potential confounders, including fatal etiology of SE, age, SE severity, and use of anesthetics (relative risk for every additional day = 2.7, p = .024). At SE onset, decreased consciousness and presumed fatal etiology predicted prolonged postictal MV. Anesthetics were associated with prolonged MV, but linear regression could not identify significant correlations.

SIGNIFICANCE

Our data reveal that prolonged postictal MV is frequent and an independent risk factor for death. Extubation is often delayed for days despite sufficient weaning from the ventilator and altered airway-protective reflexes in only few patients. Studies need to investigate whether more rigorous extubation strategies improve outcome.

De-novo non-convulsive status epilepticus in adult medical inpatients without known epilepsy: Analysis of mortality related factors and literature review

Background

Non-convulsive status epilepticus (NCSE) often goes unnoticed and is not easily detected in patients with a decreased level of consciousness, especially in older patients. In this sense, lack of data in this population is available.

Aims

The aim of the present study was to examine daily clinical practice and evaluate factors that may influence the prognosis of NCSE in non-epileptic medical inpatients.

Methods

We conducted a retrospective analysis including patients admitted by any cause in an Internal Medicine ward. All patients with compatible symptoms, exclusion of other causes, clinical suspicion or diagnosis of NCSE, and compatible EEG were included. Patients with a previous diagnosis of epilepsy were excluded. We also conducted a literature review by searching the PubMed/Medline database with the terms: Nonconvulsive Status OR Non-Convulsive Status.

Results

We included 54 patients, mortality rate reached 37% and the main factors linked to it were hypernatremia (OR = 16.2; 95% CI, 1.6–165.6; P = 0.019) and atrial fibrillation (OR = 6.7; 95% CI, 1.7–26; P = 0.006). There were no differences regarding mortality when comparing different diagnosis approach or treatment regimens. Our literature review showed that the main etiology of NCSE were neurovascular causes (17.8%), followed by antibiotic treatment (17.2%) and metabolic causes (17%). Global mortality in the literature review, excluding our series, reached 20%.

Discussion

We present the largest series of NCSE cases in medical patients, which showed that this entity is probably misdiagnosed in older patients and is linked to a high mortality.

Conclusion

The presence of atrial fibrillation and hypernatremia in patients diagnosed with NCSE should advise physicians of a high mortality risk.

Case Report: Hypopituitarism Presenting With Nonconvulsive Status Epilepticus

Introduction: Hypopituitarism is defined as one or more partial or complete pituitary hormone deficiencies. Nonconvulsive status epilepticus (NCSE) refers to a state of continuous or repetitive seizures without convulsions. In this paper, we review a case of an old female patient with hypopituitarism who presented with NCSE, which is rare in the clinic.

Case Report: This paper describes a 67-year-old female patient with hypopituitarism who presented as NCSE. She had surgical resection of pituitary tumor half a year before the seizures and did not get regular hormone replacement therapy. She presented general convulsive status epilepsy as the initial symptom and got sedation and antiepileptic drug in the emergency room. The seizure was terminated but the patient fell in coma in the following days. The patient had magnetic resonance imaging (MRI) and other inspects, and EEG showed epileptic discharges. Combining these clinical symptoms and examinations, we made the diagnosis of NCSE. Finally, she regained consciousness after the treatment with diazepam.

Conclusion: This case report and literature review investigated the possible mechanism of hypopituitarism presenting with NCSE.

Altered mental status in moderate-severe traumatic brain injury in Indonesia: the clinical manifestation and EEG features of non-convulsive status epilepticus

Introduction

Moderate-to-severe traumatic brain injury (msTBI) can cause non-convulsive status epilepticus (NCSE). Electroencephalography (EEG) is employed as a diagnostic tool due to the non-specificity of clinical symptoms. This study aimed to identify clinical and EEG features related to NCSE in patients with msTBI.

Methods

This was a cross-sectional study. Suspected NCSE in msTBI was examined using EEG data collected in consecutive patients from January 2017 to December 2019 at Dr. Cipto Mangunkusumo Hospital, Jakarta. Diagnoses of NCSE were made based on clinical manifestations and EEG features using the modified Salzburg Consensus Criteria for NCSE (mSCNC).

Results

Of the 39 msTBI patients, 19 were diagnosed with NCSE; only two fulfilled the definitive criteria, and the remaining were possible NCSE. Delirium and perceptual impairment were only found in NCSE, while psychomotor agitation was higher (12.8% vs. 5.1% in NCSE vs. non-NCSE). The most common EEG feature was rhythmic activity (>0.5 Hz) without fluctuation, which improved with anti-epileptic drug administration. The Glasgow Coma Scale (GCS) score at onset and at hospitalisation discharge was significantly lower in patients with NCSE. The lesions in NCSE mostly originated from the temporal lobe. Injury to the temporal lobe had a significant relationship with NCSE occurrence (p = 0.036, odds ratio 11.45 [95% confidence interval 1.17–111.6]).

Discussion

Post-traumatic NCSE can manifest as an alteration in mental status that could lead to missed diagnosis. In this study, delirium, perceptual impairment, and psychomotor agitation were confirmed as NCSE using EEG. The most common discharge originated from the injured temporal lobe, and this site was a significant factor associated with NCSE in patients with msTBI.

Conclusion

NCSE can be found in msTBI cases with clinical manifestations of altered mental status, psychomotor agitation, and hallucination. An injured temporal lobe was a susceptible site for the development of NCSE.

Prediction of Postictal Delirium Following Status Epilepticus in the ICU: First Insights of an Observational Cohort Study

OBJECTIVES

To identify early predictors of postictal delirium in adult patients after termination of status epilepticus.

DESIGN

Retrospective study.

SETTING

ICUs at a Swiss tertiary academic medical center.

PATIENTS

Status epilepticus patients treated on the ICUs for longer than 24 hours from 2012 to 2018.

INTERVENTIONS

None.

METHODS

Primary outcome was postictal delirium during post-status epilepticus treatment defined as an Intensive Care Delirium Screening Checklist greater than or equal to 4. Associations with postictal delirium were secondary outcomes. A time-dependent multivariable Cox proportional hazards model was used to identify risks of postictal delirium. It included variables that differed between patients with and without delirium and established risk factors for delirium (age, sex, number of inserted catheters, illness severity [quantified by the Sequential Organ Failure Assessment and Status Epilepticus Severity Score], neurodegenerative disease, dementia, alcohol/drug consumption, infections, coma during status epilepticus, dose of benzodiazepines, anesthetics, and mechanical ventilation).

MEASUREMENTS AND MAIN RESULTS

Among 224 patients, post-status epilepticus Intensive Care Delirium Screening Checklist was increased in 83% with delirium emerging in 55% with a median duration of 2 days (interquartile range 1-3 d). Among all variables, only the history of alcohol and/or drug consumption was associated with increased hazards for delirium in multivariable analyses (hazard ratio = 3.35; 95% CI, 1.53-7.33).

CONCLUSIONS

Our study provides first exploratory insights into the risks of postictal delirium in adult status epilepticus patients treated in the ICU. Delirium following status epilepticus is frequent, lasting mostly 2-3 days. Our findings that with the exception of a history of alcohol and/or drug consumption, other risk factors of delirium were not found to be associated with a risk of postictal delirium may be related to the limited sample size and the exploratory nature of our study. Further investigations are needed to investigate the role of established risk factors in other status epilepticus cohorts. In the meantime, our results indicate that the risk of delirium should be especially considered in patients with a history of alcohol and/or drug consumption.

Safety and Efficacy of Coma Induction Following First-Line Treatment in Status Epilepticus: A 2-Center Study

OBJECTIVE

To explore the safety and efficacy of artificial coma induction to treat status epilepticus (SE) immediately after first-line antiseizure treatment instead of following the recommended approach of first using second-line drugs.

METHODS

Clinical and electrophysiologic data of all adult patients treated for SE from 2017 to 2018 in the Swiss academic medical care centers from Basel and Geneva were retrospectively assessed. Primary outcomes were return to premorbid neurologic function and in-hospital death. Secondary outcomes were the emergence of complications during SE, duration of SE, and intensive care unit (ICU) and hospital stays.

RESULTS

Of 230 patients, 205 received treatment escalation after first-line medication. Of those, 27.3% were directly treated with artificial coma and 72.7% with second-line nonanesthetic antiseizure drugs. Of the latter, 16.6% were subsequently put on artificial coma after failure of second-line treatment. Multivariable analyses revealed increasing odds for coma induction after first-line treatment with younger age, the presence of convulsions, and an increased SE severity as quantified by the Status Epilepticus Severity Score (STESS). While outcomes and complications did not differ compared to patients with treatment escalation according to the guidelines, coma induction after first-line treatment was associated with shorter SE duration and ICU and hospital stays.

CONCLUSIONS

Early induction of artificial coma is performed in more than every fourth patient and especially in younger patients presenting with convulsions and more severe SE. Our data demonstrate that this aggressive treatment escalation was not associated with an increase in complications but with shorter duration of SE and ICU and hospital stays.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that early induction of artificial coma after unsuccessful first-line treatment for SE is associated with shorter duration of SE and ICU and hospital stays compared to the use of a second-line nonanesthetic antiseizure drug instead of or before anesthetics, without an associated increase in complications.

Diagnostic yield of cerebrospinal fluid analysis in status epilepticus: an 8-year cohort study

Background

We investigate the frequency and diagnostic yield of cerebrospinal fluid (CSF) analysis in adult patients with status epilepticus (SE) and its impact on the outcome.

Methods

From 2011 to 2018, adult patients treated at the University Hospital Basel were included. Primary outcomes were defined as the frequency of lumbar puncture and results from chemical, cellular, and microbiologic CSF analyses. Secondary outcomes were differences between patients receiving and not receiving lumbar puncture in the context of SE.

Results

In 18% of 408 patients, a lumbar puncture was performed. Of those, infectious pathogens were identified in 21% with 15% detected ± 24 h around SE diagnosis. 74% of CSF analyses revealed abnormal chemical or cellular components without infectious pathogens. Screening for autoimmune diseases was only performed in 22%. In 8%, no or late (i.e., > 24 after SE diagnosis) lumbar puncture was performed despite persistent unknown SE etiology in all, transformation into refractory SE in 78%, and no recovery to premorbid neurologic function in 66%. Withholding lumbar puncture was associated with no return to premorbid neurologic function during hospital stay independent of potential confounders. Not receiving a lumbar puncture was associated with presumed known etiology and signs of systemic infectious complications.

Conclusions

Withholding lumbar puncture in SE patients is associated with increased odds for no return to premorbid neurologic function, and CSF analyses in SE detect infectious pathogens frequently. These results and pathologic chemical and cellular CSF findings in the absence of infections call for rigorous screening to confirm or exclude infectious or autoimmune encephalitis in this context which should not be withheld.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-021-10447-3.

Therapy delay in status epilepticus extends its duration and worsens its prognosis

BACKGROUND

Timing in status epilepticus (SE) attention is probably the most relevant modifiable prognostic factor and may influence SE duration and prognosis. We aimed to describe the precise relationship between management timing, duration, and prognosis of SE.

METHODS

Observational longitudinal prospective study on a cohort of all patients diagnosed with SE admitted to our tertiary hospital from September 2017 to August 2019, with a 3-month follow-up. Univariate and multivariable analyses were performed to identify clinical and timing variables associated with SE duration and prognosis.

RESULTS

Eighty-three SE affecting 76 patients were included. Median age was 73 years, 61.4% were women, median baseline modified Rankin Scale (mRS) was 2, and 55.4% had prior epilepsy. In the out-of-hospital group (n = 50), median time to emergencies was 1.3 h and to hospital admission 2.8 h. In the global series, median time to neurologist was 4.3 h, and median time to therapy initiation was 4.5 h. These four times positively correlated with SE duration (all Spearman's rho coefficient >0.5, all p < .001). SE median duration was 24 h and was extended 1.2 h for each hour of treatment delay. A longer SE duration was associated with increased mortality and morbidity, both at hospital discharge and at 3-month follow-up (both p < .05). After 3 months, mortality was 30.1%, while recovery to baseline mRS occurred in 39.5%, with an overall median mRS of 4.

CONCLUSIONS

There were pervasive delays in all phases of SE attention, which conditioned a longer SE duration, and this led to increased long-term morbimortality.

Modeling the economic value of Ceribell Rapid Response EEG in the inpatient hospital setting

AIMS

Potentially life-threatening diagnosis of non-convulsive status epilepticus (NCSE) can only be confirmed with electroencephalography (EEG). When access to EEG is limited, physicians may empirically treat, risking unnecessary sedation and intubation, or not treat, increasing risk of refractory seizures. Either may prolong hospital length of stay (LOS). The current study aimed to examine the effect of a new EEG system (Ceribell Rapid Response EEG, Rapid-EEG) on hospital costs by enabling easy access to EEG and expedited seizure diagnosis and treatment.

MATERIALS AND METHODS

We built a two-armed decision-analytic cost-benefit model comparing Rapid-EEG with clinical suspicion alone for NCSE. Diagnostic parameters were informed by a multicenter clinical trial (DECIDE, NCT03534258), while LOS and cost parameters were from public US inpatient data, published literature, and Center for Medicare and Medicaid Services fee schedules. We calculated reference case estimates from mean values, while uncertainty was assessed using 95% prediction intervals (PI) generated by probabilistic sensitivity analysis (PSA) and ANCOVA sum of squares. All costs were indexed to 2019 US$.

RESULTS

Each use case of Rapid-EEG saved $3,971 to $17,290 as it led to reduction in the hospital LOS by 1.2 days (6.1 vs. 7.4 days) and ICU LOS by 0.4 days (1.5 vs. 1.9 days). Using PSA, Rapid-EEG saving was $5,633 per use case (95% PI: $($4,649 to $6,617), as it led to diminished hospital LOS by 1.1 days (95% PI: 0.9-1.4 days) and reduced ICU LOS by 0.5 days (95% PI: 0.4-0.6 days). Cost-savings were demonstrated in 75% of replications. Sixty-four percent of variance in total costs was attributable to LOS for persons incorrectly diagnosed with seizures.

LIMITATIONS

Results were obtained from the analysis of existing data and not a prospective outcome trial.

CONCLUSIONS

Rapid-EEG alters the treatment course for patients with suspected seizures and will result in cost savings per patient.

Treatments for Convulsive and Nonconvulsive Status Epilepticus in Adults: An Expert Opinion Survey in South Korea

BACKGROUND AND PURPOSE

The aim of this study was to survey the expert opinions on treatments for convulsive status epilepticus (CSE) and nonconvulsive status epilepticus (NCSE) in adults.

METHODS

Forty-two South Korean epileptologists participated in this survey. They completed an online questionnaire regarding various patient scenarios and evaluated the appropriateness of medications used to treat CSE and NCSE.

RESULTS

Initial treatment with a benzodiazepine (BZD) followed by either a second BZD or an antiepileptic drug (AED) monotherapy was the preferred treatment strategy. More than two-thirds of the experts used a second BZD when the first one failed, and consensus was reached for 84.8% of the survey items. The preferred BZD was intravenous (IV) lorazepam for the initial treatment of status epilepticus. IV fosphenytoin and IV levetiracetam were chosen for AED monotherapy after the failure of BZD. The treatments for NCSE were similar to those for CSE. Continuous IV midazolam infusion was the treatment of choice for iatrogenic coma in refractory CSE, but other AEDs were preferred over iatrogenic coma in refractory NCSE.

CONCLUSIONS

The results of this survey are consistent with previous guidelines, and can be cautiously applied in clinical practice when treating patients with CSE or NCSE.

Electroclinical patterns in patients with nonconvulsive status epilepticus: Etiology, treatment, and outcome

INTRODUCTION

This study investigated the clinical and electroencephalography (EEG) features and prognostic factors of patients with nonconvulsive status epilepticus (NCSE).

MATERIALS AND METHODS

We retrospectively reviewed the clinical files and EEG data of 45 (28 females, mean age 54 ± 22.6 years) consecutive patients with NCSE over a five-year period. An EEG interpreter who was blinded to the clinical findings evaluated the EEGs according to the Salzburg Consensus Criteria (SCC) for NCSE. Patient demographics, etiology, neuroimaging and laboratory data, EEG features, treatment, and outcome measures were analyzed.

RESULTS

The most common etiology for NCSE was acute symptomatic etiologies (57.8%) and cerebrovascular disease (48.9%). The majority (68.9%) of the patients presented with new-onset status epilepticus (SE). NCSE was refractory to treatment in 31.1% of patients. The most common status pattern consisted of rhythmic delta/theta activity in 62.3% of EEGs. Twenty-five status patterns on the EEGs were classified as definite, 30 as possible, and six as no NCSE according to the SCC. The in-hospital mortality rate was high (33.3%) showing an association with potentially fatal etiology, refractory SE, treatment with continuous I.V. anesthetics and also the presence of multiple status patterns and nonreactivity in EEGs (p < 0.05).

CONCLUSIONS

The SCC for NCSE have high diagnostic accuracy but do not affect prognosis. Potentially fatal etiology, multiple status patterns on EEG and non-reactive EEGs may carry significantly greater risk for short-term mortality.

Antiepileptic Drug Therapy for Status Epilepticus

Status epilepticus (SE) is one of the most serious neurologic emergencies. SE is a condition that encompasses a broad range of semiologic subtypes and heterogeneous etiologies. The treatment of SE primarily involves the management of the underlying etiology and the use of antiepileptic drug therapy to rapidly terminate seizure activities. The Drug Committee of the Korean Epilepsy Society performed a review of existing guidelines and literature with the aim of providing practical recommendations for antiepileptic drug therapy. This article is one of a series of review articles by the Drug Committee and it summarizes staged antiepileptic drug therapy for SE. While evidence of good quality supports the use of benzodiazepines as the first-line treatment of SE, such evidence informing the administration of second- or third-line treatments is lacking; hence, the recommendations presented herein concerning the treatment of established and refractory SE are based on case series and expert opinions. The choice of antiepileptic drugs in each stage should consider the characteristics and circumstances of each patient, as well as their estimated benefit and risk to them. In tandem with the antiepileptic drug therapy, careful searching for and treatment of the underlying etiology are required.

Non-Convulsive Status Epilepticus in the Presence of Catatonia: A Clinically Focused Review

INTRODUCTION

Catatonia is classically associated with psychiatric conditions but may occur in medical and neurologic disorders. Status epilepticus (SE) is a seizure lasting more than five minutes or two or more seizures within a five-minute period without interictal recovery of consciousness. Non-convulsive status epilepticus (NCSE) is SE without prominent motor activity that may present with catatonic symptoms. The relevance of NCSE as a potential etiology for catatonia is not clear in the literature.

METHODS

A systematic review was completed to evaluate the literature on NCSE presenting with catatonia. PubMed and PsycInfo databases were searched and articles were reviewed for the presence of catatonia and NCSE.

RESULTS

15 articles describing 27 cases meeting inclusion criteria were identified. The authors add 1 case to the literature. The most common catatonic symptoms identified in NCSE were mutism and stupor. Clinical features frequent in NCSE presenting with catatonia included new catatonic symptoms, age over 50 years, comorbid neurological conditions, or a change in medications that affect seizure threshold. A documented psychiatric history was also common and may contribute to delayed diagnosis.

DISCUSSION/CONCLUSION

It is important to consider NCSE in the differential diagnosis of new catatonic symptoms. A suggested approach to diagnostic evaluation is provided.

Hyperperfusion in the thalamus on arterial spin labelling indicates non-convulsive status epilepticus

Non-convulsive status epilepticus describes the syndrome of unexplained impaired consciousness in critically ill patients. Non-convulsive status epilepticus is very likely to lead to delayed diagnosis and poor outcomes because of the absence of convulsive symptoms. EEG is essential for the diagnosis of non-convulsive status epilepticus to establish the association between periodic discharges and rhythmic delta activity in addition to ictal epileptiform discharges according to the Salzburg criteria. Arterial spin labelling, a type of perfusion MRI, has been applied for rapid and non-invasive evaluation of the ictal state. Ictal cerebral cortical hyperperfusion is the most common finding to demonstrate focal onset seizures. Hyperperfusion of the thalamus on single photon emission computed tomography was found in patients with impaired awareness seizures. We hypothesized that thalamocortical hyperperfusion on arterial spin labelling identifies non-convulsive status epilepticus and such thalamic hyperperfusion specifically associates with periodic/rhythmic discharges producing impaired consciousness without convulsion. We identified 27 patients (17 females; age, 39-91 years) who underwent both arterial spin labelling and EEG within 24 h of suspected non-convulsive status epilepticus. We analysed 28 episodes of suspected non-convulsive status epilepticus and compared hyperperfusion on arterial spin labelling with periodic/rhythmic discharges. We evaluated 21 episodes as a positive diagnosis of non-convulsive status epilepticus according to the Salzburg criteria. We identified periodic discharges in 15 (12 lateralized and 3 bilateral independent) episodes and rhythmic delta activity in 13 (10 lateralized, 1 bilateral independent and 2 generalized) episodes. Arterial spin labelling showed thalamic hyperperfusion in 16 (11 unilateral and 5 bilateral) episodes and cerebral cortical hyperperfusion in 24 (20 unilateral and 4 bilateral) episodes. Thalamic hyperperfusion was significantly associated with non-convulsive status epilepticus (P = 0.0007; sensitivity, 76.2%; specificity, 100%), periodic discharges (P < 0.0001; 93.3%; 84.6%), and rhythmic delta activity (P = 0.0006; 92.3%; 73.3%). Cerebral cortical hyperperfusion was significantly associated with non-convulsive status epilepticus (P = 0.0017; 100%; 57.1%) and periodic discharges (P = 0.0349; 100%; 30.8%), but not with rhythmic delta activity. Thalamocortical hyperperfusion could be a new biomarker of non-convulsive status epilepticus according to the Salzburg criteria in critically ill patients. Specific thalamic hyperexcitability might modulate the periodic discharges and rhythmic delta activity associated with non-convulsive status epilepticus. Impaired consciousness without convulsions could be caused by predominant thalamic hyperperfusion together with cortical hyperperfusion but without ictal epileptiform discharges.

Clinical features and outcomes of nonconvulsive status epilepticus in a developing country: A 5-year retrospective study

BACKGROUND

This study aimed to determine the frequency of electrographically confirmed nonconvulsive status epilepticus (NCSE) in a cohort suspected with this condition and to determine the demographic/clinical profile, treatment, and outcomes of these patients in the context of a developing country, the Philippines.

METHODS

We conducted a retrospective study among patients with suspected with NCSE admitted in the Philippine General Hospital from 2014 to 2019. Using the Salzberg 2013 criteria to diagnose NCSE, three electroencephalographers independently reviewed the electroencephalogram (EEG) tracings of suspected patients and were blinded from the clinical information. Then, we obtained pertinent clinical data from the medical records of EEG-confirmed NCSE cases.

RESULTS

Out of 89 patients suspected with NCSE and with available EEG tracings, information from a total of 14 patients (15.7%) with electrographically confirmed cases were included in the analysis. Median age was 52 ranging from 22 to 77 and female-to-male ratio was 1.3:1. The following conditions were associated with NCSE: intracranial tumor (n = 4), metabolic encephalopathy (n = 4), autoimmune encephalitis (n = 3), intracranial hemorrhage (n = 3), sepsis (n = 3), cardiac arrest (n = 2), hypoxic-ischemic injury (n = 2), antiepileptic withdrawal (n = 1), intracranial abscess (n = 1), head trauma (n = 1), and meningitis (n = 1). Three patients (21.4%) had relatively good clinical outcomes (mRS 0-2) while 6 patients (42.8%) had poor outcomes (mRS 3-5) at discharge. Five patients (35.7%) died due to medical/neurological complications. Our review of the literature showed that the profile of NCSE cases identified in our resource-limited institution strengthens the findings in other populations.

CONCLUSION

Our data showed that approximately 1 in 6 patients who are suspected with NCSE may have electrographic evidence of NCSE in our setting. The most common etiologies associated with NCSE were intracranial tumors and metabolic conditions. Further studies may entail a prospective collection of data to validate the estimates of our study.

Sporadic Creutzfeldt-Jakob disease with tau pathology mimicking new-onset refractory non-convulsive status epilepticus: Case report and review of the literature

BACKGROUND AND PURPOSE

The aim of our study is to review the relationship between NCSE and sCJD. Creutzfeldt-Jakob disease (CJD) is the most common form of human prion disease. Electroencephalography (EEG)-detected changes such as periodic sharp wave complexes, superimposable to those seen in non-convulsive epileptic status (NCSE), have only rarely been described at CJD onset, especially in sporadic CJD (sCJD) cases.

METHODS

We describe clinical, EEG, cerebrospinal fluid (CSF) and neuroimaging findings of a confirmed case of sCJD with tau pathology, initially diagnosed as NCSE. We performed a literature review in PubMed of previous publications on both sCJD and NCSE.

RESULTS

An 82-year-old woman with no medical history presented with a 2-week rapidly progressive neurological disorder, with motor aphasia, myoclonus, pyramidalism, and left posterior alien hand. EEG showed periodic sharp waves on right frontal regions, so anti-epileptic treatment was started. CSF results were normal. Brain magnetic resonance imaging demonstrated hyperintensity of the right cerebral cortex in diffusion sequences. Due to suspected new-onset refractory status epilepticus (NORSE), corticosteroid treatment was started, without clinical improvement. Necropsy results confirmed sCJD with tau pathology. The literature review identified 14 references including a total of 18 cases with NCSE as the presenting symptom of sCJD; the clinical and results in complementary tests were compiled into a table.

CONCLUSIONS

Sporadic CJD should be considered in the differential diagnosis of patients with rapid cognitive decline and EEG changes consistent with NCSE. The wide heterogeneity in the etiology of NCSE, including autoimmune disorders, especially NORSE, suggests immunotherapy should be initiated based on a good risk-benefit balance. Some cases of sCJD, such as the present case with tau pathology, may mimic this clinico-electrical course.

Frequency and Implications of Complications in the ICU After Status Epilepticus: No Calm After the Storm

OBJECTIVES

To investigate the frequency, types, and implications of complications during intensive care in patients after status epilepticus has been successfully terminated.

DESIGN

Retrospective study.

SETTING

ICUs at a Swiss tertiary academic medical care center.

PATIENTS

Data were collected from the digital patient records of all adult patients with status epilepticus from 2012 to 2018.

INTERVENTIONS

None.

METHODS

Primary outcomes were defined as frequency of complications following status epilepticus termination and return to premorbid functional baseline. Univariable analyses regarding the relative risks of complications occurring after status epilepticus termination for no return to premorbid neurologic function were estimated by Poisson regression with robust error variance.

RESULTS

Of 311 patients with status epilepticus, 224 patients (72%) were treated on the ICU for more than 24 hours following status epilepticus termination. Ninety-six percent of patients remained in a prolonged state of altered consciousness for a median of 2 days (interquartile range, 1-3 d) and 80% had complications during their ICU treatment. Fifty-five percent had new-onset delirium with a median duration of 2 days (interquartile range, 1-3 d). Forty-two percent had mechanical ventilation for a median of 4 days (interquartile range, 2-11 d) and 21% had nosocomial infections diagnosed after status epilepticus. Multivariable analyses revealed that mechanical ventilation for more than 24 hours after status epilepticus, and arterial hypotension requiring vasopressors were independently associated with increased risk of no return to premorbid function (RRfor each additional day = 1.01; 95% CI, 1.02-1.03 and RRfor each additional day = 1.03; 95% CI, 1.01-1.05) and death (RRfor each additional day = 1.11; 95% CI, 1.04-1.19 and RRfor each additional day = 1.15; 95% CI, 1.03-1.28). Delirium was independently associated with a decreased relative risk of death (RRfor each additional day = 0.55; 95% CI, 0.37-0.80), but prolonged ICU- and hospital stays.

CONCLUSIONS

Complications after status epilepticus termination are frequent and associated with no return to premorbid function, death, and prolonged ICU- and hospital stays. These results call for heightened awareness and further studies mainly regarding prediction and preventive strategies in this context.

Status Epilepticus: Definition, Classification, Pathophysiology, and Epidemiology

Status epilepticus (SE) is the state of continuous or repetitive seizures, which can occur with or without convulsions. Evolving definitions of SE take into account the concept that neuronal injury may occur at different times in different types of SE.SE that does not respond to initial treatment may become refractory or even super-refractory. Nonconvulsive SE is increasingly recognized in comatose patients in critical care units, with the growing use of continuous electroencephalogram monitoring. SE is a neurologic emergency that carries a high risk of mortality and morbidity.

Inhibition of p38 MAPK regulates epileptic severity by decreasing expression levels of A1R and ENT1

Epilepsy is a chronic nervous system disease. Excessive increase of the excitatory neurotransmitter glutamate in the body results in an imbalance of neurotransmitters and excessive excitation of neurons, leading to epileptic seizures. Long‑term recurrent seizures lead to behavior and cognitive changes, and even increase the risk of death by 2‑ to 3‑fold relative to the general population. Adenosine A1 receptor (A1R), a member of the adenosine system, has notable anticonvulsant effects, and adenosine levels are controlled by the type 1 equilibrative nucleoside transporter (ENT1); in addition the p38 MAPK signaling pathway is involved in the regulation of ENT1, although the effect of its inhibitors on the expression levels of A1R and ENT1 is unclear. Therefore, in the present study, SB203580 was used to inhibit the p38 MAPK signaling pathway in rats, and the expression levels of A1R and ENT1 in the brain tissue of rats with acute LiCl‑pilocarpine‑induced status epilepticus was detected. SB203580 decreased pathological damage of hippocampal neurons, prolonged seizure latency, reduced the frequency of seizures, and decreased levels of A1R and ENT1 protein in rats.

Accuracy of Calculated Free Valproate Levels in Adult Patients With Status Epilepticus

OBJECTIVE

To test the accuracy of an equation in adult patients with status epilepticus that calculates the free concentration of serum valproic acid (fVPA) from the total concentration of serum valproic acid (tVPA) and serum albumin.

METHODS

All adult patients with status epilepticus who were treated at a Swiss academic medical center between 2005 and 2018 with concurrent measurements of tVPA, fVPA, and serum albumin were included. fVPA was categorized as subtherapeutic, therapeutic (5-10 mg/L), or supratherapeutic. Agreement was defined as the proportion of measured and calculated fVPA falling within the same category.

RESULTS

Of 676 patients with status epilepticus, 104 had 506 measurements, with a median of 3 (interquartile range [IQR] 1.5-6.5) per patient. The median tVPA was 43.5 mg/L (27.4-63.6), with measured fVPA 9.1 mg/L (4.5-14.7) and calculated fVPA 10.1 mg/L (7.0-13.0), respectively. The median deviation of calculated from measured fVPA was -0.8 mg/L (-3.2 to 2.5) with 336 measurements >1 mg/L. While the association between measured and calculated fVPA was linear (regression coefficient 1.1, 95% confidence interval 0.9-1.2, p < 0.0001), the agreement on effective drug levels did not match in 39.8% of measurements regardless of serum albumin levels, with calculated fVPA overestimating measured fVPA in 30.4%. tVPA and serum albumin independently influenced the accuracy of the calculated fVPA in the multivariable model.

CONCLUSIONS

Calculated fVPA is inaccurate when using the proposed equation in adult patients with status epilepticus, calling for drug monitoring based on measured fVPA in this context.

Dexamethasone as Abortive Treatment for Refractory Seizures or Status Epilepticus in the Inpatient Setting

Refractory seizures or status epilepticus (RS/SE) continues to be a challenge in the inpatient setting. Failure to abort a seizure with antiepileptic drugs (AEDs) may lead to intubation and treatment with general anesthesia exposing patients to complications, extending hospitalization, and increasing the cost of care. Studies have shown a key role of inflammatory mediators in seizure generation and termination. We describe 4 patients with RS/SE that was aborted when dexamethasone was added to conventional AEDs: a 61-year-old female with temporal lobe epilepsy who presented with delirium, nonconvulsive status epilepticus, and oculomyoclonic status; a 56-year-old female with history of traumatic left frontal lobe hemorrhage who developed right face and hand epilepsia partialis continua followed by refractory focal clonic seizures; a 51-year-old male with history of traumatic intracranial hemorrhage who exhibited left-sided epilepsia partialis continua; and a 75-year-old female with history of breast cancer who manifested nonconvulsive status epilepticus and refractory focal clonic seizures. All patients continued experiencing RS/SE despite first- and second-line therapy, and one patient continued to experience RS/SE despite third-line therapy. Failure to abort RS/SE with conventional therapy motivated us to administer intravenous dexamethasone. A 10-mg load was given (except in one patient) followed by 4.0- 5.2 mg q6h. All clinical and electrographic seizures stopped 3-4 days after starting dexamethasone. When dexamethasone was discontinued 1-3 days after seizures stopped, all patients remained seizure-free on 2-3 AEDs. The cessation of RS/SE when dexamethasone was added to conventional antiseizure therapy suggests that inflammatory processes are involved in the pathogenesis of RS/SE.

Seizures associated with coronavirus infections

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Seizures have been reported in patients with various coronavirus infections.

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However, seizures seem to be a rare occurrence in people with COVID-19.

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Patients with COVID-19 may have hypoxia, multiorgan failure, and metabolic disarrangements.

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It is plausible to expect acute symptomatic seizures to happen in these patients.

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One should be prepared to treat seizures appropriately.

Neurotropic and neuroinvasive capabilities of coronaviruses have been described in humans. Neurological problems found in patients with coronavirus infection include: febrile seizures, convulsions, loss of consciousness, encephalomyelitis, and encephalitis. Coronavirus disease (COVID-19) is caused by SARS-CoV2. In severe cases, patients may develop severe pneumonia, acute respiratory distress syndrome, and acute cardiac injury. While seizures and status epilepticus have not been widely reported in the past five months since the onset of COVID-19 pandemic, patients with COVID-19 may have hypoxia, multiorgan failure, and severe metabolic and electrolyte disarrangements; hence, it is plausible to expect clinical or subclinical acute symptomatic seizures to happen in these patients. One should be prepared to treat seizures appropriately, if they happen in a patient who is already in a critical medical condition and suffers from organ failure.

HMGB1 Is a Therapeutic Target and Biomarker in Diazepam-Refractory Status Epilepticus with Wide Time Window

Status epilepticus (SE), a life-threatening neurologic emergency, is often poorly controlled by the current pharmacological therapeutics, which are limited to a narrow time window. Here, we investigated the proinflammatory cytokine high mobility group box-1 (HMGB1) as a candidate therapeutic target for diazepam (DZP)-refractory SE. We found that HMGB1 was upregulated and translocated rapidly during refractory SE period. Exogenous HMGB1 was sufficient to directly induce DZP-refractory SE in nonrefractory SE. Neutralization of HMGB1 with an anti-HMGB1 monoclonal antibody decreased the incidence of SE and alleviated the severity of seizure activity in DZP-refractory SE, which was mediated by a Toll-like receptor 4 (TLR4)-dependent pathway. Importantly, anti-HMGB1 mAb reversed DZP-refractory SE with a wide time window, extending the therapeutic window from 30 to 180 min. Furthermore, we found the upregulation of plasma HMGB1 level is closely correlated with the therapeutic response of anti-HMGB1 mAb in DZP-refractory SE. All these results indicated that HMGB1 is a potential therapeutic target and a useful predictive biomarker in DZP-refractory SE.