Jan Claassen

Jan Claassen
Columbia University | CU · Department of Neurology

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525
Publications
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Publications

Publications (525)
Article
Background and Objectives Status epilepticus that continues after the initial benzodiazepine and a second anticonvulsant medication is known as refractory status epilepticus (RSE). Management is highly variable as adequately powered clinical trials are missing. We aimed to determine if propofol and midazolam were equally effective in controlling RS...
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Background Recovery trajectories of clinically unresponsive patients with acute brain injury are largely uncertain. Brain activation in the absence of a behavioural response to spoken motor commands can be detected by EEG, also known as cognitive-motor dissociation. We aimed to explore the role of cognitive-motor dissociation in predicting time to...
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Background The use of processed electroencephalography (pEEG) for depth of sedation (DOS) monitoring is increasing in anesthesia; however, how to use of this type of monitoring for critical care adult patients within the intensive care unit (ICU) remains unclear. Methods A multidisciplinary panel of international experts consisting of 21 clinician...
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Background Hematoma and perihematomal edema volumes are important radiographic markers in spontaneous intracerebral hemorrhage. Accurate, reliable, and efficient quantification of these volumes will be paramount to their utility as measures of treatment effect in future clinical studies. Both manual and semi-automated quantification methods of hema...
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Background/Objective: There have been numerous reports of neurological manifestations identified in hospitalized patients infected with SARS-CoV-2, the virus that causes COVID-19. Here, we identify the spectrum of associated neurological symptoms and diagnoses, define the time course of their development, examine readmission rates and mortality ris...
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Background: Prolonged external ventricular drainage (EVD) in patients with subarachnoid hemorrhage (SAH) leads to morbidity, whereas early removal can have untoward effects related to recurrent hydrocephalus. A metric to help determine the optimal time for EVD removal or ventriculoperitoneal shunt (VPS) placement would be beneficial in preventing...
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This proceedings article presents actionable research targets on the basis of the presentations and discussions at the 2nd Curing Coma National Institutes of Health (NIH) symposium held from May 3 to May 5, 2021. Here, we summarize the background, research priorities, panel discussions, and deliverables discussed during the symposium across six maj...
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Background: Dysfunctional cerebral autoregulation often precedes delayed cerebral ischemia (DCI). Currently, there are no data-driven techniques that leverage this information to predict DCI in real time. Our hypothesis is that information using continuous updated analyses of multimodal neuromonitoring and cerebral autoregulation can be deployed t...
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Objective: Estimate time to recovery of command-following and associations between hypoxemia with time to recovery of command-following METHODS: In this multi-center, retrospective, cohort study during the initial surge of the United States' pandemic (March-July 2020) we estimate the time from intubation to recovery of command-following, using Kap...
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Objectives: Early consciousness disorder (ECD) after acute ischemic stroke (AIS) is understudied. ECD may influence outcomes and the decision to withdraw life-sustaining treatment (WOLST). Methods: We studied patients with AIS from 2010-2019 across 122 Florida Hospitals participating in the Florida Stroke Registry. We studied the effect of ECD o...
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Background The objective of this study was to evaluate the accuracy of seizure burden in patients with super-refractory status epilepticus (SRSE) by using quantitative electroencephalography (qEEG).MethodsEEG recordings from 69 patients with SRSE (2009–2019) were reviewed and annotated for seizures by three groups of reviewers: two board-certified...
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Background: Characterization of coronavirus disease 2019 (COVID-19) endotypes may help explain variable clinical presentations and response to treatments. While risk factors for COVID-19 have been described, COVID-19 endotypes have not been elucidated. Objectives: We sought to identify and describe COVID-19 endotypes of hospitalized patients. Metho...
Preprint
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Background The literature related to the use of processed EEG (pEEG) for depth of sedation (DOS) monitoring is increasing, however it is unclear how to use this type of monitoring for critical care patients within the intensive care unit (ICU). Methods We performed a systematic review of the literature according to the Grade of Recommendation asses...
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Background and Purpose Impaired level of consciousness (LOC) on presentation at hospital admission in patients with intracerebral hemorrhage (ICH) may affect outcomes and the decision to withhold or withdraw life-sustaining treatment (WOLST). Methods Patients with ICH were included across 121 Florida hospitals participating in the Florida Stroke R...
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Background Consciousness in patients with brain injury is traditionally assessed based on semiological evaluation at the bedside. This classification is limited because of low granularity, ill-defined and rigid nomenclatures incompatible with the highly fluctuating nature of consciousness, failure to identify specific brain states like cognitive mo...
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Coma and disorders of consciousness (DoC) are highly prevalent and constitute a burden for patients, families, and society worldwide. As part of the Curing Coma Campaign, the Neurocritical Care Society partnered with the National Institutes of Health to organize a symposium bringing together experts from all over the world to develop research targe...
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Background The current state of the science regarding the care and prognosis of patients with disorders of consciousness is limited. Scientific advances are needed to improve the accuracy, relevance, and approach to prognostication, thereby providing the foundation to develop meaningful and effective interventions.Methods To address this need, an i...
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Background: Intracranial pressure waveform morphology reflects compliance, which can be decreased by ventriculitis. We investigated whether morphologic analysis of intracranial pressure dynamics predicts the onset of ventriculitis. Methods: Ventriculitis was defined as culture or Gram stain positive cerebrospinal fluid, warranting treatment. We...
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Background Prevalence and etiology of unconsciousness are uncertain in hospitalized patients with coronavirus disease 2019 (COVID-19). We tested the hypothesis that increased inflammation in COVID-19 precedes coma, independent of medications, hypotension, and hypoxia.Methods We retrospectively assessed 3203 hospitalized patients with COVID-19 from...
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Background Electroencephalography (EEG) findings following cardiovascular collapse in death are uncertain. We aimed to characterize EEG changes immediately preceding and following cardiac death.Methods We retrospectively analyzed EEGs of patients who died from cardiac arrest while undergoing standard EEG monitoring in an intensive care unit. Patien...
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Background Vaccine induced immune medicated thrombocytopenia or VITT, is a recent and rare phenomenon of thrombosis with thrombocytopenia, frequently including cerebral venous thromboses (CVT), that has been described following vaccination with adenovirus vaccines ChAdOx1 nCOV-19 (AstraZeneca) and Ad26.COV2·S Johnson and Johnson (Janssen/J&J). The...
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Objective To determine the ability of quantitative electroencephalography (QEEG) to improve the accuracy of predicting recovery of consciousness by post-cardiac arrest day 10. Methods Unconscious survivors of cardiac arrest undergoing daily clinical and EEG assessments through post-cardiac arrest day 10 were studied in a prospective observational...
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Many patients with SARS-CoV-2 infection develop neurological signs and symptoms, though, to date, little evidence exists that primary infection of the brain is a significant contributing factor. We present the clinical, neuropathological, and molecular findings of 41 consecutive patients with SARS-CoV-2 infections who died and underwent autopsy in...
Preprint
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Many patients with SARS-CoV-2 infection develop neurological signs and symptoms, though, to date, little evidence exists that primary infection of the brain is a significant contributing factor. We present the clinical, neuropathological, and molecular findings of 41 consecutive patients with SARS-CoV-2 infections who died and underwent autopsy in...
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Acute platelet transfusion after intracerebral hemorrhage (ICH) given in efforts to reverse antiplatelet medication effects and prevent ongoing bleeding does not appear to improve outcome and may be associated with harm. Although the underlying mechanisms are unclear, the influence of ABO-incompatible platelet transfusions on ICH outcomes has not b...
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Background: Impaired level of consciousness (LOC) on presentation after acute ischemic stroke (AIS) may affect outcomes and the decision to withdraw life-sustaining treatment (WLST). We aim to investigate the outcomes and their trends after AISby the LOC on stroke presentation. Methods: We studied 238,989 cases with AIS in the Florida Stroke Regist...
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Background: Impaired level of consciousness (LOC) on presentation after intracerebral hemorrhage (ICH) may affect outcomes and the decision to withdraw life-sustaining treatment (WLST). We aim to investigate the outcomes and trends after ICH by the LOC status on presentation. Methods: We studied 37,613 cases with ICH in the Florida Stroke Registry...
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Background and Purpose Delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage negatively impacts long-term recovery but is often detected too late to prevent damage. We aim to develop hourly risk scores using routinely collected clinical data to detect DCI. Methods A DCI classification model was trained using vital sign measureme...
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Critical illness and sepsis are commonly associated with subclinical seizures. COVID-19 frequently causes severe critical illness, but the incidence of electrographic seizures in patients with COVID-19 has been reported to be low. This retrospective case series assessed the incidence of and risks for electrographic seizures in patients hospitalized...
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Objective Behaviorally unresponsive patients in intensive care units (ICU) are unable to consistently and effectively communicate their most fundamental physical needs. Brain-Computer Interface (BCI) technology has been established in the clinical context, but faces challenges in the critical care environment. Contrary to cue-based BCIs, which allo...
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Objective To study if limited frontotemporal electroencephalogram (EEG) can guide sedation changes in highly infectious novel coronavirus disease 2019 (COVID-19) patients receiving neuromuscular blocking agent. Methods 98 days of continuous frontotemporal EEG from 11 consecutive patients was evaluated daily by an epileptologist to recommend reduct...
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Substantial progress has been made over the past two decades in detecting, predicting and promoting recovery of consciousness in patients with disorders of consciousness (DoC) caused by severe brain injuries. Advanced neuroimaging and electrophysiological techniques have revealed new insights into the biological mechanisms underlying recovery of co...
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Abstract The brainstem conveys sensory and motor inputs between the spinal cord and the brain, and contains nuclei of the cranial nerves. It controls the sleep-wake cycle and vital functions via the ascending reticular activating system and the autonomic nuclei, respectively. Brainstem dysfunction may lead to sensory and motor deficits, cranial ner...
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Background Low red blood cell (RBC) levels are associated with worse intracerebral hemorrhage (ICH) outcomes. However, relationships of RBC transfusions on ICH outcomes are unclear given the overlap of RBC transfusion, comorbidities, and disease severity. We investigated RBC transfusion relationships on ICH outcomes while accounting for comorbiditi...
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Purpose of review: Recovery after severe brain injury is variable and challenging to accurately predict at the individual patient level. This review highlights new developments in clinical prognostication with a special focus on the prediction of consciousness and increasing reliance on methods from data science. Recent findings: Recent research...
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Seizures are common in critically ill patients. Electroencephalogram (EEG) is a tool that enables clinicians to provide continuous brain monitoring and to guide treatment decisions—brain telemetry. EEG monitoring has particular utility in the intensive care unit as most seizures in this setting are nonconvulsive. Despite the increased use of EEG mo...
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Introduction: We have shown that cardiac arrest-induced psychological distress is associated with an increased risk of cardiovascular disease (CVD) events and death. Low physical activity (PA) is a known risk factor for recurrent CVD events. We hypothesize that aversive cognitions about PA due to fear of trauma-related bodily sensations may lead to...
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Introduction: In light of the COVID-19 pandemic, various emergency medical services (EMS) and health agencies in New York City (NYC), and other hard-hit cities, issued new guidelines terminating resuscitation efforts in cases of out of hospital cardiac arrests (CA). This guidance was issued to protect the health and safety of EMS providers, to cons...
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Introduction: Patients with cardiovascular disease conditions are at high risk for direct and indirect impacts of COVID-19 on morbidity and mortality. In light of this, we aimed to assess the extent to which COVID-19-related anxiety in patients with a history of cardiac arrest (CA) correlates with the desire to change or discuss advanced directives...
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Introduction: Cardiac arrest (CA) patients’ fear of contracting Coronavirus disease 2019 (COVID-19) may limit their ability or willingness to perform cardio-protective health behaviors. We assessed the association of COVID-19 anxiety with physical activity (PA), sleep, and the likelihood of seeking medical care. Methods: Between May 15-28, 2020, a...
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Background The modified Fisher scale (mFS) is a critical clinical and research tool for risk stratification of cerebral vasospasm. As such, the mFS is included as a common data element by the National Institute of Neurological Disorders and Stroke SAH Working Group. There are few studies assessing the interrater reliability of the mFS.Methods We di...
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Objective Assessment of the impact of cerebrospinal fluid (CSF) analysis including investigation for the presence of SARS-CoV-2 is essential for the optimization of patient care. Methods In this case series, we review patients diagnosed with SARS-CoV-2 undergoing LP admitted to Columbia University Irving Medical Center (New York, New York) from Ma...
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Background: Critically-ill COVID-19 patients have frequent thrombotic complications and laboratory evidence of hypercoagulability. The relationship of coagulation tests and thrombosis requires investigation to identify best diagnostic and treatment approaches. We assessed for hypercoagulable characteristics in critically-ill COVID-19 patients usin...
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Objective: To better understand the heterogeneous population of patients with new-onset refractory status epilepticus (NORSE), we studied the most severe cases who presented with new-onset super refractory status epilepticus (NOSRSE). Methods: We report a retrospective case series of 26 adults admitted to the Columbia University Irving Medical C...
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Objective To test ketamine infusion efficacy in the treatment of super-refractory status epilepticus (SRSE), we studied retrospectively SRSE patients who were treated with ketamine. Additionally, we studied the effect of high doses of ketamine on brain physiology as reflected by invasive multimodality monitoring (MMM). Methods We studied a consecu...
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Status epilepticus (SE) is a neurologic emergency with high morbidity and mortality. The assessment of a patient's prognosis is crucial in making treatment decisions. In this review, we discuss various markers that have been used to prognosticate SE in terms of recurrence, mortality, and functional outcome. These markers include demographic, clinic...
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Introduction Hematoma expansion (HE) is associated with poor outcome in intracerebral hemorrhage (ICH) patients, but the impact on left ventricular assist device (LVAD) patients is unknown. We aimed to define the occurrence of HE in the LVAD population and to determine the association between HE and mortality. Materials & Methods We performed a re...
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The analysis of spontaneous EEG activity and evoked potentials is a cornerstone of the instrumental evaluation of patients with disorders of consciousness (DoC). The past few years have witnessed an unprecedented surge in EEG-related research applied to the prediction and detection of recovery of consciousness after severe brain injury, opening up...
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Coma and disordered consciousness are common manifestations of acute neurological conditions and are among the most pervasive and challenging aspects of treatment in neurocritical care. Gaps exist in patient assessment, outcome prognostication, and treatment directed specifically at improving consciousness and cognitive recovery. In 2019, the Neuro...
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Objective The mental health toll of COVID-19 on healthcare workers (HCW) is not yet fully described. We characterized distress, coping, and preferences for support among NYC HCWs during the COVID-19 pandemic. Methods This was a cross-sectional web survey of physicians, advanced practice providers, residents/fellows, and nurses, conducted during a...
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Background Infection and venous thromboembolism (VTE) are associated with worse outcomes after intracerebral hemorrhage (ICH). The relationship between infection and VTE in ICH patients is unclear. We hypothesized that infection would be associated with subsequent VTE after ICH.Methods We retrospectively studied consecutively admitted spontaneous p...
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Background Over 40 000 patients with COVID-19 have been hospitalised in New York City (NY, USA) as of April 28, 2020. Data on the epidemiology, clinical course, and outcomes of critically ill patients with COVID-19 in this setting are needed. Methods This prospective observational cohort study took place at two NewYork-Presbyterian hospitals affil...
Preprint
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Objective: To develop a machine learning based tool, using routine vital signs, to assess delayed cerebral ischemia (DCI) risk over time. Methods: In this retrospective analysis, physiologic data for 540 consecutive acute subarachnoid hemorrhage patients were collected and annotated as part of a prospective observational cohort study between May 20...
Preprint
Background: Nearly 30,000 patients with coronavirus disease-2019 (COVID-19) have been hospitalized in New York City as of April 14th, 2020. Data on the epidemiology, clinical course, and outcomes of critically ill patients with COVID-19 in this setting are needed. Methods: We prospectively collected clinical, biomarker, and treatment data on critic...
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Background: Sentinel headache (SH) is often assumed to portend an increased risk of delayed cerebral ischemia (DCI) and aneurysm rebleeding. This study aimed to re-evaluate the associations between SH and aneurysm rebleeding, DCI, and outcome after SAH. Methods: We retrospectively analyzed 1102 patients with spontaneous SAH and available data re...
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Background: There are radiographic and clinical outcome differences between patients with deep and lobar intracerebral hemorrhage (ICH) locations. Pilot studies suggest that there may be functional coagulation differences between these locations detectable using whole blood coagulation testing. Objective: To confirm the presence of interlocation...
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Consciousness is a highly significant indicator of an ICU patient's condition but there is still no method to automatically measure it. Instead, time consuming and subjective assessments are used. However, many brain and physiologic variables are measured continuously in neurological ICU, and could be used as indicators for consciousness. Since man...
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Background Benzodiazepine-refractory, or established, status epilepticus is thought to be of similar pathophysiology in children and adults, but differences in underlying aetiology and pharmacodynamics might differentially affect response to therapy. In the Established Status Epilepticus Treatment Trial (ESETT) we compared the efficacy and safety o...
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Background: Key dimensions of cardiac arrest-induced posttraumatic stress disorder (PTSD) symptoms include reexperiencing, avoidance, numbing, and hyperarousal. It remains unknown which dimensions are most predictive of outcome. Purpose: To determine which dimensions of cardiac arrest-induced PTSD are predictive of clinical outcome within 13 mon...
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Introduction: There is conflicting evidence of the risks and benefits of platelet transfusions after intracerebral hemorrhage (ICH). Current practice does not necessitate the transfusion of ABO matched platelets despite evidence that platelet recovery is suboptimal in patients receiving ABO incompatible platelet transfusions. Hypothesis: We hypothe...
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Background: To estimate the frequency of post-sudden cardiac arrest survivorship (PSCAS) problems (i.e., cognitive impairment, disability in activities of daily living, depression and posttraumatic stress disorder (PTSD)). Methods: We prospectively enrolled adults with return of spontaneous circulation after in-hospital or out-of-hospital CA betwee...
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Purpose of review: Status epilepticus is a neurological emergency associated with high morbidity and mortality. There is a lack of robust data to guide the management of this neurological emergency beyond the initial treatment. This review examines recent literature on treatment considerations including the choice of continuous anesthetics or adju...
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South America is a subcontinent with 393 million inhabitants with widely distinct countries and diverse ethnicities, cultures, political and societal organizations. The epidemiological transition that accompanied the technological and demographic evolution is happening in South America and leading to a rise in the incidence of neurodegenerative and...