Electrographic Status Epilepticus Research Articles

Clinical and laboratory predictors of electrographic status epilepticus in the neurological intensive care.

Clinical and laboratory predictors of electrographic status epilepticus in the neurological intensive care.

Electrographic Status Epilepticus Terminated by Acute Thalamic Stimulation.

Electrographic Status Epilepticus Terminated by Acute Thalamic Stimulation.

Post-hypoxic status epilepticus - A distinct subtype of status epilepticus with poor prognosis.

To evaluate the clinical outcome of patients with possible and definitive post-hypoxic status epilepticus (SE) and to describe the SE types in patients with definitive post-hypoxic SE. Patients with definitive or possible SE resulting from hypoxic brain injury after cardiac arrest (CA) were prospectively recruited. Intermittent EEG was used for the diagnosis of SE according to clinical practice. Two raters blinded to outcome analyzed EEGs retrospectively for possible and definitive SE patterns and background features (frequency, continuity, reactivity, and voltage). Definitive SE was classified according to semiology (ILAE). Mortality and Cerebral Performance Categories (CPC) score were evaluated 1 month after CA. We included 64 patients of whom 92% died. Among the survivors, only one patient had a good neurological outcome (CPC 1). No patient survived with a burst suppression pattern, low voltage, or electro-cerebral silence in any EEG. Possible or definitive SE was diagnosed in a median of 47 h (IQR 39-72 h) after CA. EEG criteria for definitive electrographic SE were fulfilled in 39% of patients; in 38% - for electroclinical SE and in 23% - for ictal-interictal continuum (IIC). The outcome did not differ significantly between the three groups. The only patient with good functional outcome belonged to the IIC group. Comatose non-convulsive SE (NCSE) without subtle motor phenomenon occurred in 20% of patients with definitive electrographic SE and outcome was similar to other types of SE. Possible or definitive SE due to hypoxic brain injury is associated with poor prognosis. The outcome of patients with electrographic SE, electroclinical SE, and IIC did not differ significantly. Outcome was similar in patients with definitive electrographic SE with and without prominent motor features.

Diagnosis and management of seizures and myoclonus after cardiac arrest.

Cardiac arrest may lead to postanoxic brain injury. In approximately one third of the patients who remain in coma, myoclonus or status myoclonus is seen. Clinically manifest or electrographic epileptic seizures or status epilepticus are less common. Both status myoclonus and electrographic seizures indicate severe brain injury. Electroencephalography can contribute to discrimination between epileptic seizures and postanoxic myoclonus, as well as to identification of patients that may have a good outcome or can benefit from treatment. Accumulating data suggest that extensive anti-seizure treatment is futile in case of general periodic discharges. On the other hand, the small subgroup of patients with EEG patterns closely resembling electrographic seizures or status epilepticus may benefit from anti-seizure treatment, but the evidence of efficacy is weak. Medication to suppress clinically manifest myoclonus may be necessary for general ICU care and mechanical ventilation, but does not improve a patient's prognosis.

Transcutaneous electrical stimulation of auricular branch of the vagus nerve effectively and rapidly modulates the EEG patterns in patients with possible electrographic status epilepticus.

Invasive vagal nerve stimulation (iVNS) is a known treatment approach for patients with refractory epilepsy. Transcutaneous auricular vagus nerve stimulation (tVNS) was developed to overcome the side effects and surgical complications of iVNS. tVNS is proven beneficial in refractory epilepsy. The effectiveness of tVNS, however, has never been studied in patients with Status Epilepticus. In this study, we explored the effect of tVNS in three patients with possible electrographic status epilepticus. To compare the EEG pattern before, during and after tVNS in three patients with possible electrographic status epilepticus. Three consecutive patients with possible electrographic status epilepticus were included after due consenting process. In addition to the standard care, tVNS was applied on the left ear over the cymba concha in two sessions, 6 h apart, with each session for 45 min. Continuous EEG monitoring was performed as standard of care and the findings before, during and after tVNS were documented. The duration of status epilepticus at the time of inclusion of Patients 1, 2, and 3 was 6 weeks, 7 days, and 5 days respectively. All were in coma and on multiple antiseizure medications. Patient 1 and 3 were on anesthetic infusions. Before stimulation, one patient had burst suppression pattern and two had generalized periodic discharges at 1 Hz frequency. We observed a significant reduction/resolution of ongoing EEG patterns in all three patients during the stimulation. The abnormal patterns re-emerged approximately 20 min post cessation of tVNS. No stimulation-related side effects were detected. There was no change in clinical status, but all three patients had severe underlying conditions. Transcutaneous auricular Vagus Nerve Stimulation (tVNS) is a potential noninvasive adjuvant therapy that can modulate EEG patterns in patients with Status epilepticus. Larger studies in early SE are needed to assess its clinical benefits.

Evaluation of Automated Seizure Detection Measurements in Cardiac Arrest Patients Undergoing Ceribell Rapid-EEG (S30.009)

<h3>Objective:</h3> To retrospectively evaluate the performance of the Clarity™ automated seizure detection system (Ceribell, Inc) for the detection of seizures and status epilepticus in cardiac arrest patients. <h3>Background:</h3> In cardiac arrest patients who remain comatose after return of spontaneous circulation, seizures and EEG abnormalities are common. Thus, guidelines recommend urgent EEG initiation for evaluation of seizures in this population. Point-of-care EEG systems, such as Ceribell™ Rapid-EEG, allow for prompt initiation of EEG monitoring, albeit through a limited-channel montage. Rapid-EEG incorporates an automated seizure detection software (Clarity™) to measure seizure burden in real time and alert clinicians when a high seizure burden, consistent with possible status epilepticus, is identified. External validation of Clarity is still needed. <h3>Design/Methods:</h3> This study was a retrospective review of Ceribell Rapid-EEG recordings from all the patients who were admitted to the medical intensive care unit at Kent Hospital (Warwick, RI, USA) between 6/1/2021 and 3/18/2022 for management after cardiac arrest and who underwent Rapid-EEG monitoring as part of their routine clinical care (n=21). Board-certified epileptologists identified events that met criteria for seizures or status epilepticus, as per the 2021 American Clinical Neurophysiology Society’s Standardized Critical Care EEG Terminology, and evaluated any seizure burden detections generated by Clarity. <h3>Results:</h3> In this study, 4 of 21 cardiac arrest patients (19.0%) who underwent Rapid-EEG monitoring had multiple electrographic seizures, and 2 of those patients (9.5%) had electrographic status epilepticus within the first 24 hours of the study. None of these ictal abnormalities were detected by the Clarity seizure detection system. Clarity showed 0% seizure burden during all these events. <h3>Conclusions:</h3> The presence of frequent seizures and/or status epilepticus may go undetected by currently available automated seizure detection systems. Timely and careful review of all raw Rapid-EEG recordings by a qualified human EEG reader is necessary to guide clinical care. <b>Disclosure:</b> Dr. Villamar has a non-compensated relationship as a Member of Editorial Board with Neurology: Clinical Practice that is relevant to AAN interests or activities. Dr. Villamar has a non-compensated relationship as a Member of Editorial Board with The Neurohospitalist that is relevant to AAN interests or activities. The institution of Dr. Ayub has received research support from Brown Physicians Incorporated. Dr. Koenig has received personal compensation in the range of $5,000-$9,999 for serving on a Speakers Bureau for Fuji SonoSite. Dr. Koenig has received personal compensation in the range of $5,000-$9,999 for serving on a Speakers Bureau for Medscape.

Myoclonus in comatose patients with electrographic status epilepticus after cardiac arrest: Corresponding EEG patterns, effects of treatment and outcomes

ObjectiveTo clarify the significance of any form of myoclonus in comatose patients after cardiac arrest with rhythmic and periodic EEG patterns (RPPs) by analyzing associations between myoclonus and EEG pattern, response to anti-seizure medication and neurological outcome. DesignPost hoc analysis of the prospective randomized Treatment of ELectroencephalographic STatus Epilepticus After Cardiopulmonary Resuscitation (TELSTAR) trial. SettingEleven ICUs in the Netherlands and Belgium. PatientsOne hundred and fifty-seven adult comatose post-cardiac arrest patients with RPPs on continuous EEG monitoring. InterventionsAnti-seizure medication vs no anti-seizure medication in addition to standard care. Measurements and Main ResultsOf 157 patients, 98 (63%) had myoclonus at inclusion. Myoclonus was not associated with one specific RPP type. However, myoclonus was associated with a smaller probability of a continuous EEG background pattern (48% in patients with vs 75% without myoclonus, odds ratio (OR) 0.31; 95% confidence interval (CI) 0.16–0.64) and earlier onset of RPPs (24% vs 9% within 24 hours after cardiac arrest, OR 3.86;95% CI 1.64–9.11). Myoclonus was associated with poor outcome at three months, but not invariably so (poor neurological outcome in 96% vs 82%, p = 0.004). Anti-seizure medication did not improve outcome, regardless of myoclonus presence (6% good outcome in the intervention group vs 2% in the control group, OR 0.33; 95% CI 0.03–3.32). ConclusionsMyoclonus in comatose patients after cardiac arrest with RPPs is associated with poor outcome and discontinuous or suppressed EEG. However, presence of myoclonus does not interact with the effects of anti-seizure medication and cannot predict a poor outcome without false positives.

Automated Seizure Detection in Patients with Cardiac Arrest: A Retrospective Review of Ceribell™ Rapid-EEG Recordings.

In patients with cardiac arrest who remain comatose after return of spontaneous circulation, seizures and other abnormalities on electroencephalogram (EEG) are common. Thus, guidelines recommend urgent initiation of EEG for the evaluation of seizures in this population. Point-of-care EEG systems, such as Ceribell™ Rapid Response EEG (Rapid-EEG), allow for prompt initiation of EEG monitoring, albeit through a reduced-channel montage. Rapid-EEG incorporates an automated seizure detection software (Clarity™) to measure seizure burden in real time and alert clinicians at the bedside when a high seizure burden, consistent with possible status epilepticus, is identified. External validation of Clarity is still needed. Our goal was to evaluate the real-world performance of Clarity for the detection of seizures and status epilepticus in a sample of patients with cardiac arrest. This study was a retrospective review of Rapid-EEG recordings from all the patients who were admitted to the medical intensive care unit at Kent Hospital (Warwick, RI) between 6/1/2021 and 3/18/2022 for management after cardiac arrest and who underwent Rapid-EEG monitoring as part of their routine clinical care (n = 21). Board-certified epileptologists identified events that met criteria for seizures or status epilepticus, as per the 2021 American Clinical Neurophysiology Society's Standardized Critical Care EEG Terminology, and evaluated any seizure burden detections generated by Clarity. In this study, 4 of 21 patients with cardiac arrest (19.0%) who underwent Rapid-EEG monitoring had multiple electrographic seizures, and 2 of those patients (9.5%) had electrographic status epilepticus within the first 24h of the study. None of these ictal abnormalities were detected by the Clarity seizure detection system. Clarity showed 0% seizure burden throughout the entirety of all four Rapid-EEG recordings, including the EEG pages that showed definite seizures or status epilepticus. The presence of frequent electrographic seizures and/or status epilepticus can go undetected by Clarity. Timely and careful review of all raw Rapid-EEG recordings by a qualified human EEG reader is necessary to guide clinical care, regardless of Clarity seizure burden measurements.

A Commentary on Electrographic Seizure Management and Clinical Outcomes in Critically Ill Children

Continuous EEG (cEEG) monitoring is the gold standard for detecting electrographic seizures in critically ill children and the current consensus-based guidelines recommend urgent cEEG to detect electrographic seizures that would otherwise be undetected. The detection of seizures usually leads to the use of antiseizure medications, even though current evidence that treatment leads to important improvements in outcomes is limited, raising the question of whether the current strategies need re-evaluation. There is emerging evidence indicating that the presence of electrographic seizures is not associated with unfavorable neurological outcome, and thus treatment is unlikely to alter the outcomes in these children. However, a high seizure burden and electrographic status epilepticus is associated with unfavorable outcome and the treatment of status epilepticus is currently warranted. Ultimately, outcomes are more likely a function of etiology than of a direct effect of the seizures themselves. We suggest re-examining our current consensus toward aggressive treatment to abolish all electrographic seizures and recommend a tailored approach where therapeutic interventions are indicated when seizure burden breaches above a critical threshold that may be associated with adverse outcomes. Future studies should explicitly evaluate whether there is a positive impact of treating electrographic seizures or electrographic status epilepticus in order to justify continuing current approaches.

Comparison between 1.5-Tesla pseudocontinuous and pulsed arterial spin labeling in visualizing peri-ictal hyperperfusion: A case report

Arterial spin labeling (ASL) imaging with multiple postlabeling delays (PLD) can demonstrate the hemodynamics of peri-ictal hyperperfusion. Labeling methods include pulsed ASL (PASL) and pseudocontinuous ASL (pCASL). Although PASL is more widely used in daily clinical practice, it has several disadvantages because of lower delivery of labeled magnetization. We compared pCASL and PASL images acquired after a 24-h interval, using a 1.5-Tesla machine, in a 62-year-old man with non-convulsive status epilepticus. The pCASL during electrographic status epilepticus clearly demonstrated that ASL signals in the grey matter of the right hemisphere, particularly in the posteromedial part of the right temporal lobe, increased at PLDs of 1.5 s and 1.75 s and were almost washed out at 2.0 s. Although PASL, which was obtained during the ictal-interictal continuum when there were no changes in ictal findings on diffusion-weighted images, showed a similar trend, the increased signals were less pronounced than those of pCASL, with more contamination of arte-rial transit artifact in the subarachnoid space. Although the electroencephalographic findings were not the same when both ASLs were performed, the present study confirms that PASL is somewhat inferior to pCASL in detecting peri-ictal hyperperfusion because of the greater effect of arterial transient artifacts.

Curriculum Innovations: High-Fidelity Simulation of Acute Neurology Enhances Rising Resident Confidence

Introduction &amp; Problem Statement The matriculation from internal medicine to neurology residency can be challenging. The most cogent approach to address this transition has yet to be identified. Studies show that simulation is highly effective at reinforcing knowledge and skills while improving learner confidence. We present the design and outcomes of an annual acute neurology simulation program. Objectives We hypothesized that incoming neurology residents would (1) report improved confidence with managing acute neurologic emergencies, (2) cite a high degree of educational value with the program, and (3) demonstrate improvement in their technical knowledge. Methods &amp; Curriculum Description Our military, level 1 trauma institution's simulation laboratory and staff were used to develop and execute simulations for rising neurology residents based on the Accreditation Council for Graduate Medical Education neurology milestones. Three simulations were designed including a case of acute ischemic stroke (AIS), status epilepticus (SE) in an austere environment, and brain death evaluation with family counseling. Residents completed matched pre‐ and post assessments to gauge confidence, technical knowledge, and perceived educational value. Results &amp; Assessment Data Over 3 years, 15 rising neurology residents from 2 training programs completed 3 high-fidelity acute neurology cases. Self-reported confidence with acute neurology skills improved after each simulation. Confidence ratings included assessing for and identifying contraindications to tissue plasminogen activator, identifying AIS, identifying clot retrieval candidates, identifying clinical and electrographic SE, diagnosing and treating SE, identifying contraindications to and confounders of brain death diagnosis, performing the examination, and delivering bad news to families (all p &lt; 0.05). Technical knowledge also statistically improved in the stroke (p = 0.046) and brain death simulation (p = 0.039), but not the SE simulation (p = 0.296). Participants reported an average perceived personal value of 4.8, 4.3, and 4.7 (out of a maximum of 5) for AIS, SE, and brain death simulations, respectively. Discussion &amp; Lessons Learned High-fidelity simulation of neurologic emergencies enhances confidence and knowledge of rising neurology residents. Satisfaction with the simulation cases was high. Academic hospitals can consider incorporating acute neurology simulations into their residency training.

VEEG monitoring and electrographic seizures in 232 pediatric patients in ICU at a tertiary hospital in China.

To investigate neonatal electroencephalography (EEG) background activity and electrographic seizures in patients in the pediatric intensive care unit (PICU) who underwent bedside video-electroencephalography (vEEG) monitoring. A total of 232 pediatric patients admitted or transferred to PICU that underwent vEEG monitoring were retrospectively enrolled in this study, and electrographic status epilepticus was observed after vEEG monitoring. The median age was 1.56 years [95% confidence interval (CI) = 1.12-2.44]. Electrographic seizures occurred in 88 patients (37.9%), out of which 36 cases (40.9%) had electrographic status epilepticus. Prior epileptic encephalopathy diagnosis [odds ratio (OR) = 6.57, 95% CI = 1.91-22.59, p = 0.003], interictal epileptiform discharges (OR = 46.82, 95%CI = 5.31-412.86, p = 0.0005), slow disorganized EEG background (OR = 11.92, 95%CI = 1.31-108.71, p = 0.028), and burst-suppression EEG background (OR = 23.64, 95%CI = 1.71-327.57, p = 0.018) were the risk factors for electrographic seizures' occurrence. Of the 232 patients, the condition of 179 (77.2%) patients improved and they were discharged, 34 cases (14.7%) were withdrawn, and 18 cases (7.8%) died. The in-hospital death rate was 47.6% (10 in 21 cases) in patients with attenuated/featureless, compared to 0/23 with normal EEG background. Electrographic status epilepticus occurs in more than one-third of patients with electrographic seizures. vEEG is an efficient method to determine electrographic seizures in children. Abnormal EEG background activity is associated with both electrographic seizures' occurrence and unfavorable in-hospital outcomes.

Electrographic Seizures in Neonates with a High Risk of Encephalopathy.

Background: Neonatal encephalopathy is caused by a wide variety of acute brain insults in newborns and presents with a spectrum of neurologic dysfunction, such as consciousness disturbance, seizures, and coma. The increased excitability in the neonatal brain appears to be highly susceptible to seizures after a variety of insults, and seizures may be the first clinical sign of a serious neurologic disorder. Subtle seizures are common in the neonatal period, and abnormal clinical paroxysmal events may raise the suspicion of neonatal seizures. Continuous video electroencephalographic (EEG) monitoring is the gold standard for the diagnosis of neonatal seizures. The aim of this study was to identify the prevalence of electrographic seizures and the impact of monitoring in neonates with a high risk of encephalopathy. Methods: We conducted this prospective cohort study in a tertiary neonatal intensive care unit over a 4-year period. Neonates with a high risk of encephalopathy who were receiving continuous video EEG monitoring were eligible. The patients were divided into 2 groups: (1) acute neonatal encephalopathy (ANE) and (2) other high-risk encephalopathy conditions (OHRs). The neonates’ demographic characteristics, etiologies, EEG background feature, presence of electrographic seizures and the impact of monitoring were analyzed. Results: A total of 71 neonates with a high risk of encephalopathy who received continuous video EEG monitoring were enrolled. In this consecutive cohort, 42 (59.2%) were monitored for ANE and 29 (40.8%) were monitored for OHRs. At the time of starting EEG monitoring, 54 (76.1%) of the neonates were term infants. The median gestational age at monitoring was 39 weeks (interquartile range, 37–41 weeks). The median total EEG monitoring duration was 64.7 h (interquartile range, 22.2–72.4 h). Electrographic seizures were captured in 25 of the 71 (35.2%) neonates, of whom 20 (80%) had electrographic-only seizures without clinical correlation. Furthermore, of these 20 neonates, 13 (65%) developed electrographic status epilepticus. Electrographic seizures were most commonly found in the ANE group (17, 40.5%) than in the OHRs group (8, 27.6%) (p = 0.013). Besides, normal/mild abnormality and inactive EEG background were less electrographic seizure than moderate and major abnormality EEG background (2 of 30, 6.7% vs. 23 of 41, 56.1%, p < 0.001). Finally, continuous video EEG monitoring excluded the diagnosis of electrographic seizures in two-thirds of the monitored neonates who had paroxysmal events mimicking seizures and led to a change in clinical management in 39.4% of the neonates. Conclusions: Our findings showed that monitoring could accurately detect seizures, and that it could be used to guide seizure medication management. Therefore, continuous video EEG monitoring has important clinical management implications in neonates with a high risk of encephalopathy.

Time-dependent neuropathology in rats following organophosphate-induced status epilepticus

Exposure to high levels of a cholinesterase inhibiting organophosphorus (OP) agent often results in seizures that progress to status epilepticus (SE). Survivors of OP-induced SE often display neuropathological consequences the days following SE. In the current study, the temporal profile of neuropathology after SE was investigated in a rat model of diisopropylfluorophosphate (DFP)-induced SE. Adult Sprague-Dawley rats were injected with DFP to induce SE for one hour. Following termination of electrographic SE with urethane (0.8 g/kg, sc), cohorts of rats were euthanized 3, 24 and 48 h later and brain tissue was processed to determine immediate early gene and inflammatory mediator expression as well as blood-brain barrier changes and neurodegeneration. After SE rats displayed a time-dependent upregulation of immediate early genes such as cFos and ΔFosB as well as pro-inflammatory mediators COX-2, IL-1β and IL-6. The profile of positive cFos staining, but not ΔFosB, coincided temporally with heightened brain activity measured by cortical electroencephalography (EEG). Neurodegeneration in limbic brain regions was absent 3 h after SE, but prominent 24 h later and continued to increase 48 h after SE. Serum albumin was detected in the cortex 3 h after SE suggesting early loss of blood brain barrier integrity. However, the blood-brain barrier appeared repaired 48 h after SE. This study demonstrates that following OP-poisoning in rats, immediate early gene expression in the brain precedes neuroinflammation followed by erosion of the blood-brain barrier and neurodegeneration. The study also demonstrates that seizure activity in brain nuclei coincides with cFos expression. Together, these studies give insight into the temporal molecular changes in the brain following organophosphate-induced status epilepticus.

The Spike-Wave Index of the First 100 Seconds of Sleep Can Be a Reliable Scoring Method for Electrographic Status Epilepticus in Sleep.

Electrical status epilepticus in sleep (ESES) is an electrographic pattern in which interictal epileptiform activity is augmented by the transition to sleep, with non-rapid eye movement sleep state characterized by near-continuous lateralized or bilateral epileptiform discharges. The aim of this study was to measure the reliability of the spike-wave index (SWI) of the first 100 seconds of sleep as a tool for the diagnosis of ESES. One hundred forty studies from 60 unique patients met the inclusion. Two neurophysiologists calculated the SWI of the first 100 seconds of spontaneous stage II non-rapid eye movement sleep. This was compared with the SWI of the first 5 minutes of non-rapid eye movement sleep and the cumulative SWI of three 5-minute bins of sleep. Agreement between the three SWI methods were analyzed using several statistical tools and methods. Using an SWI of 50% as a diagnostic cutoff, 57% of records had a diagnosis of ESES based on the first 100 seconds of sleep. Fifty-four percent of records had a diagnosis of ESES based on the method of using the SWI of three bins. This resulted in a diagnostic accuracy of 92%, sensitivity of 96%, and specificity of 88%. Positive predictive values of children diagnosed with ESES using the first 100 seconds of sleep, compared with 3 combined bins, was determined to be 90% and a negative predictive value was determined to be 95%. This analysis confirmed the diagnostic accuracy of using the SWI of the first 100 seconds of sleep and the cumulative total of three 5-minute bins.

Serum neurofilament light as a biomarker of neurodegeneration in status epilepticus

Neurofilaments (Nf) are intermediate filaments specifically expressed in neurons. Nf might be released from damaged or diseased axons in significant amounts into blood and cerebrospinal fluid (CSF) thus, they could be used as potential biomarkers of neurodegeneration. Elevation of serum Neurofilaments Light (sNfL) has been reported in drug resistant epilepsy and in post-anoxic electrographic status epilepticus. The purpose was to evaluate sNfL in patients with Status Epilepticus (SE).

PL6. Treatment continuum of nonconvulsive status epilepticus

Acute seizures and status epilepticus (SE) are commonly encountered in critically ill patients. With continuous EEG (cEEG) monitoring it is possible to differentiate whether patients are in on-going, continuous SE or having intermittent electrographic seizures. This data should be used to determine the urgency and aggressiveness of treatment for each patient. In this presentation the rationale for “appropriately aggressive” treatment will be discussed in the context of the risk-benefit calculus. Initially the evolving definition of SE will be discussed. This will be followed by a discussion about measuring the severity of electrographic SE, and how this is valuable in determining appropriate therapeutic targets. Finally, the concept of “appropriately aggressive” therapy for SE will be discussed.

COVID-19 Continuous-EEG Case Series: A Descriptive Study.

Corona virus disease 2019 (COVID-19) refers to coronavirus disease secondary to SARS-CoV2 infection mainly affecting the human respiratory system. The SARS-CoV2 has been reported to have neurotropic and neuroinvasive features and neurological sequalae with wide range of reported neurological manifestations, including cerebrovascular disease, skeletal muscle injury, meningitis, encephalitis, and demyelination, as well as seizures and focal status epilepticus. In this case series, we analyzed the continuous video-EEGs of patients with COVID-19 infection to determine the presence of specific EEG features or epileptogenicity. All continuous video-EEG tracings done on SARS-CoV2-positive patients during a 2-week period from April 5, 2020, to April 19, 2020, were reviewed. The demographics, clinical characteristics, imaging, and EEG features were analyzed and presented. Of 23 patients undergoing continuous video-EEG, 16 were COVID positive and were included. Continuous video-EEG monitoring was ordered for "altered mental status" in 11 of 16 patients and for "clinical seizure" in 5 of 16 patients. None of the patients had seizures or status epilepticus as a presenting symptom of COVID-19 infection. Instead, witnessed clinical seizures developed as results of COVID-19-related medical illness(es): anoxic brain injury, stroke/hemorrhage, lithium (Li) toxicity (because of kidney failure), hypertension, and renal disease. Three patients required therapeutic burst suppression because of focal nonconvulsive status epilepticus, status epilepticus/myoclonus secondary to anoxic injury from cardiac arrest, and one for sedation (and with concomitant EEG abnormalities secondary to Li toxicity). In this observational case series of 16 patients with COVID-19 who were monitored with continuous video-EEG, most patients experienced a nonspecific encephalopathy. Clinical seizures and electrographic status epilepticus were the second most commonly observed neurological problem.

Comparison of neuropathology in rats following status epilepticus induced by diisopropylfluorophosphate and soman

The increasing number of cases involving the use of nerve agents as deadly weapons has spurred investigation into the molecular mechanisms underlying nerve agent-induced pathology. The highly toxic nature of nerve agents restrict their use in academic research laboratories. Less toxic organophosphorus (OP) based agents including diisopropylfluorophosphate (DFP) are used as surrogates in academic research laboratories to mimic nerve agent poisoning. However, neuropathology resulting from DFP-induced status epilepticus (SE) has not been compared directly to neuropathology observed following nerve agent poisoning in the same study. Here, the hypothesis that neuropathology measured four days after SE is the same for rats exposed to DFP and soman was tested. Adult Sprague-Dawley rats were injected with soman or DFP to induce SE. Cortical electroencephalography (EEG) was recorded prior to and during soman-induced SE. EEG power analysis of rats administered soman revealed prolonged electrographic SE similar to that of rats that endure uninterrupted SE following injection of DFP. Rats that experienced soman-induced SE displayed less hippocampal neuroinflammation and gliosis compared to rats administered DFP. Seizure-induced weight change, blood-brain barrier (BBB) leakiness and neurodegeneration in most seizure sensitive limbic brain regions were similar for rats that endured SE following soman or DFP. The amalgamated pathology score calculated by combining pathological measures (weight loss, hippocampal neuroinflammation, gliosis, BBB integrity and neurodegeneration) was similar in rats administered the OP agents. These findings support use of the rat DFP model of SE as a suitable surrogate for investigating some, but not all delayed consequences produced by nerve agents.

Postanoxic electrographic status epilepticus and serum biomarkers of brain injury

AimTo explore if electrographic status epilepticus (ESE) after cardiac arrest causes additional secondary brain injury reflected by serum levels of two novel biomarkers of brain injury: neurofilament light chain (NfL) originating from neurons and glial fibrillary acidic protein (GFAP) from glial cells. MethodsSimplified continuous EEG (cEEG) and serum levels of NfL and GFAP, sampled at 24, 48 and 72 h after cardiac arrest, were collected during the Target Temperature Management (TTM)-trial. Two statistical methods were used: multivariable regresssion analysis; and a matched control group of patients without ESE matched for early predictors of poor neurological outcome. Results128 patients had available biomarkers and cEEG. Twenty-six (20%) patients developed ESE, the majority (69%) within 24 h. ESE was an independent predictor of elevated serum NfL (p < 0.001) but not of serum GFAP (p = 0.16) at 72 h after cardiac arrest. Compared to a control group matched for early predictors of poor neurological outcome, patients who developed ESE had higher levels of serum NfL (p = 0.03) and GFAP (p = 0.04) at 72 h after cardiac arrest. ConclusionESE after cardiac arrest is associated with higher levels of serum NfL which may suggest increased secondary neuronal injury compared to matched patients without ESE but similar initial brain injury. Associations with GFAP reflecting glial injury are less clear. The study design cannot exclude imperfect matching or other mechanisms of secondary brain injury contributing to the higher levels of biomarkers of brain injury seen in the patients with ESE.