Covert Tracking to Immersive Stimuli in Traumatic Brain Injury Subjects With Disorders of Consciousness.

Eye tracking assessments are clinician dependent and can contribute to misclassification of coma. We investigated responsiveness to videos with and without audio in traumatic brain injury (TBI) subjects using video eye-tracking (VET). We recruited 20 healthy volunteers and 10 unresponsive TBI subjects. Clinicians were surveyed whether the subject was tracking on their bedside assessment. The Coma Recovery Scale-Revised (CRS-R) was also performed. Eye movements in response to three different 30-second videos with and without sound were recorded using VET. The videos consisted of moving characters (a dancer, a person skateboarding, and Spiderman). Tracking on VET was defined as visual fixation on the character and gaze movement in the same direction of the character on two separate occasions. Subjects were classified as "covert tracking" (tracking using VET only), "overt tracking" (VET and clinical exam by clinicians), and "no tracking". A k-nearest-neighbors model was also used to identify tracking computationally. Thalamocortical connectivity and structural integrity were evaluated with EEG and MRI. The ability to obey commands was evaluated at 6- and 12-month follow-up. The average age was 29 (± 17) years old. Three subjects demonstrated "covert tracking" (CRS-R of 6, 8, 7), two "overt tracking" (CRS-R 22, 11), and five subjects "no tracking" (CRS-R 8, 6, 5, 6, 7). Among the 84 tested trials in all subjects, 11 trials (13%) met the criteria for "covert tracking". Using the k-nearest approach, 14 trials (17%) were classified as "covert tracking". Subjects with "tracking" had higher thalamocortical connectivity, and had fewer structures injured in the eye-tracking network than those without tracking. At follow-up, 2 out of 3 "covert" and all "overt" subjects recovered consciousness versus only 2 subjects in the "no tracking" group. Immersive stimuli may serve as important objective tools to differentiate subtle tracking using VET.

Prognostic and Diagnostic Utility of Serum Biomarkers in Pediatric Traumatic Brain Injury.

Traumatic brain injury (TBI) remains a major cause of morbidity and death among the pediatric population. Timely diagnosis, however, remains a complex task because of the lack of standardized methods that permit its accurate identification. The aim of this study was to determine whether serum levels of brain injury biomarkers can be used as a diagnostic and prognostic tool in this pathology. This prospective, observational study collected and analyzed the serum concentration of neuronal injury biomarkers at enrollment, 24h and 48h post-injury, in 34 children ages 0-18 with pTBI and 19 healthy controls (HC). Biomarkers included glial fibrillary acidic protein (GFAP), neurofilament protein L (NfL), ubiquitin-C-terminal hydrolase (UCH-L1), S-100B, tau and tau phosphorylated at threonine 181 (p-tau181). Subjects were stratified by admission Glasgow Coma Scale score into two categories: a combined mild/moderate (GCS 9-15) and severe (GCS 3-8). Glasgow Outcome Scale-Extended (GOS-E) Peds was dichotomized into favorable (≤4) and unfavorable (≥5) and outcomes. Data were analyzed utilizing Prism 9 and R statistical software. The findings were as follows: 15 patients were stratified as severe TBI and 19 as mild/moderate per GCS. All biomarkers measured at enrollment were elevated compared with HC. Serum levels for all biomarkers were significantly higher in the severe TBI group compared with HC at 0, 24, and 48h. The GFAP, tau S100B, and p-tau181 had the ability to differentiate TBI severity in the mild/moderate group when measured at 0h post-injury. Tau serum levels were increased in the mild/moderate group at 24h. In addition, NfL and p-tau181 showed increased serum levels at 48h in the aforementioned GCS category. Individual biomarker performance on predicting unfavorable outcomes was measured at 0, 24, and 48h across different GOS-E Peds time points, which was significant for p-tau181 at 0h at all time points, UCH-L1 at 0h at 6-9 months and 12 months, GFAP at 48h at 12 months, NfL at 0h at 12 months, tau at 0h at 12 months and S100B at 0h at 12 months. We concluded that TBI leads to increased serum neuronal injury biomarkers during the first 0-48h post-injury. A biomarker panel measuring these proteins could aid in the early diagnosis of mild to moderate pTBI and may predict neurological outcomes across the injury spectrum.

Practice Standards for the Use of Multimodality Neuromonitoring: A Delphi Consensus Process.

OBJECTIVES: To address areas in which there is no consensus for the technologies, effort, and training necessary to integrate and interpret information from multimodality neuromonitoring (MNM). DESIGN: A three-round Delphi consensus process. SETTING: Electronic surveys and virtual meeting. SUBJECTS: Participants with broad MNM expertise from adult and pediatric intensive care backgrounds. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Two rounds of surveys were completed followed by a virtual meeting to resolve areas without consensus and a final survey to conclude the Delphi process. With 35 participants consensus was achieved on 49% statements concerning MNM. Neurologic impairment and the potential for MNM to guide management were important clinical considerations. Experts reached consensus for the use of MNM-both invasive and noninvasive-for patients in coma with traumatic brain injury, aneurysmal subarachnoid hemorrhage, and intracranial hemorrhage. There was consensus that effort to integrate and interpret MNM requires time independent of daily clinical duties, along with specific skills and expertise. Consensus was reached that training and educational platforms are necessary to develop this expertise and to provide clinical correlation. CONCLUSIONS: We provide expert consensus in the clinical considerations, minimum necessary technologies, implementation, and training/education to provide practice standards for the use of MNM to individualize clinical care.

Focused Management of Patients With Severe Acute Brain Injury and ARDS.

Considering the COVID-19 pandemic where concomitant occurrence of ARDS and severe acute brain injury (sABI) has increasingly coemerged, we synthesize existing data regarding the simultaneous management of both conditions. Our aim is to provide readers with fundamental principles and concepts for the management of sABI and ARDS, and highlight challenges and conflicts encountered while managing concurrent disease. Up to 40% of patients with sABI can develop ARDS. Although there are trials and guidelines to support the mainstays of treatment for ARDS and sABI independently, guidance on concomitant management is limited. Treatment strategies aimed at managing severe ARDS may at times conflict with the management of sABI. In this narrative review, we discuss the physiological basis and risks involved during simultaneous management of ARDS and sABI, summarize evidence for treatment decisions, and demonstrate these principles using hypothetical case scenarios. Use of invasive or noninvasive monitoring to assess brain and lung physiology may facilitate goal-directed treatment strategies with the potential to improve outcome. Understanding the pathophysiology and key treatment concepts for comanagement of these conditions is critical to optimizing care in this high-acuity patient population.

Respiratory Complications and Weaning Considerations for Patients with Spinal Cord Injuries: A Narrative Review.

Respiratory complications following traumatic spinal cord injury are common and are associated with high morbidity and mortality. The inability to cough and clear secretions coupled with weakened respiratory and abdominal muscles commonly leads to respiratory failure, pulmonary edema, and pneumonia. Higher level and severity of the spinal cord injury, history of underlying lung pathology, history of smoking, and poor baseline health status are potential predictors for patients that will experience respiratory complications. For patients who may require prolonged intubation, early tracheostomy has been shown to lead to improved outcomes. Prediction models to aid clinicians with the decision and timing of tracheostomy have been shown to be successful but require larger validation studies in the future. Mechanical ventilation weaning strategies also require further investigation but should focus on a combination of optimizing ventilator setting, pulmonary toilet techniques, psychosocial well-being, and an aggressive bowel regimen.

Management of Traumatic Brain Injury: An Update.

The care of patients with traumatic brain injury can be one of the most challenging and rewarding aspects of clinical neurocritical care. This article reviews the approach to unique aspects specific to the care of this patient population. These aspects include appropriate use of sedation and analgesia, and the principles and the clinical use of intracranial monitors. Common clinical challenges encountered in these patients are also discussed, including the treatment of intracranial hypertension, temperature management, and control of sympathetic hyperactivity.

Common Patterns of Regional Brain Injury Detectable by Diffusion Tensor Imaging in Otherwise Normal-Appearing White Matter in Patients with Early Moderate to Severe Traumatic Brain Injury.

Traumatic brain injury (TBI) alters the lives of millions of people every year. Although mortality rates have improved, attributed to better pre-hospital care and reduction of secondary injury in the critical care setting, improvements in functional outcomes post-TBI have been difficult to achieve. Diffusion-tensor imaging (DTI) allows detailed measurement of microstructural damage in regional brain tissue post-TBI, thus improving our understanding of the extent and severity of TBI. Twenty subjects were recruited from a neurological intensive care unit and compared to 18 healthy control subjects. Magnetic resonance imaging (MRI) scanning was performed on a 3.0-Tesla Siemens TIM Trio Scanner (Siemens Medical Solutions, Erlangen, Germany) including T1- and T2-weighted sequences and DTI. Images were processed using DTIStudio software. SAS (SAS Institute Inc., Cary, NC) was used for statistical analysis of group differences in 14 brain regions (25 regions of interests [ROIs]). Seventeen TBI subjects completed scanning. TBI and control subjects did not differ in age or sex. All TBI subjects had visible lesions on structural MRI. TBI subjects had seven brain regions (nine ROIs) that showed significant group differences on DTI metrics (fractional anisotropy, radial diffusion, or mean diffusion) compared to noninjured subjects, including the corpus callosum (genu and splenium), superior longitudinal fasciculus, internal capsule, right retrolenticular internal capsule, posterior corona radiata, and thalamus. However, 16 ROIs showed relatively normal DTI measures. Quantitative DTI demonstrates multiple areas of microstructual injury in specific normal-appearing white matter brain regions. DTI may be useful for assessing the extent of brain injury in patients with early moderate to severe TBI.

Management of Traumatic Brain Injury: An Update.

The care of patients with traumatic brain injury can be one of the most challenging and rewarding aspects of clinical neurocritical care. This article reviews the approach to unique aspects specific to the care of this patient population. These aspects include appropriate use of sedation and analgesia, and the principles and the clinical use of intracranial monitors. Common clinical challenges encountered in these patients are also discussed, including the treatment of intracranial hypertension, temperature management, and control of sympathetic hyperactivity.

Emergency Neurological Life Support: Third Edition, Updates in the Approach to Early Management of a Neurological Emergency.

Emergency Neurologic Life Support (ENLS) is an educational program designed to provide users advisory instructions regarding management for the first few hours of a neurologic emergency. The content of the course is divided into 14 modules, each addressing a distinct category of neurological injury. The course is appropriate for practitioners and providers from various backgrounds who work in environments of variable medical complexity. The focus of ENLS is centered on a standardized treatment algorithm, checklists, to guide early patient care, and a structured format for communication of findings and concerns to other healthcare professionals. Certification and training in ENLS is hosted by the Neurocritical Care Society. This document introduces the concept of ENLS and describes revisions that constitute the third version.

Emergency Neurologic Life Support: Spinal Cord Compression.

There are many causes of acute myelopathy including multiple sclerosis, systemic disease, and acute spinal cord compression (SCC). SCC should be among the first potential causes considered given the significant permanent loss of neurologic function commonly associated with SCC. This impairment can occur over a short period of time, and may be avoided through rapid and acute surgical intervention. Patients with SCC typically present with a combination of motor and sensory dysfunction that has a distribution referable to a spinal level. Bowel and bladder dysfunction and neck or back pain may also be part of the clinical presentation, but are not uniformly present. Because interventions are critically time-sensitive, the recognition and treatment of SCC was chosen as an ENLS protocol.

Therapeutic temperature modulation is associated with pulmonary complications in patients with severe traumatic brain injury.

AIM: To examine complications associated with the use of therapeutic temperature modulation (mild hypothermia and normothermia) in patients with severe traumatic brain injury (TBI). METHODS: One hundred and fourteen charts were reviewed. Inclusion criteria were: severe TBI with Glasgow Coma Scale (GCS) < 9, intensive care unit (ICU) stay > 24 h and non-penetrating TBI. Patients were divided into two cohorts: the treatment group received therapeutic temperature modulation (TTM) with continuous surface cooling and indwelling bladder temperature probes. The control group received standard treatment with intermittent acetaminophen for fever. Information regarding complications during the time in the ICU was collected as follows: Pneumonia was identified using a combination of clinical and laboratory data. Pulmonary embolism, pneumothorax and deep venous thrombosis were identified based on imaging results. Cardiac arrhythmias and renal failure were extracted from the clinical documentation. acute respiratory distress syndrome and acute lung injury were determined based on chest imaging and arterial blood gas results. A logistic regression was conducted to predict hospital mortality and a multiple regression was used to assess number and type of clinical complications. RESULTS: One hundred and fourteen patients were included in the analysis (mean age = 41.4, SD = 19.1, 93 males), admitted to the Jackson Memorial Hospital Neuroscience ICU and Ryder Trauma Center (mean GCS = 4.67, range 3-9), were identified and included in the analysis. Method of injury included motor vehicle accident (n = 29), motor cycle crash (n = 220), blunt head trauma (n = 212), fall (n = 229), pedestrian hit by car (n = 216), and gunshot wound to the head (n = 27). Ethnicity was primarily Caucasian (n = 260), as well as Hispanic (n = 227) and African American (n = 223); four patients had unknown ethnicity. Patients received either TTM (43) or standard therapy (71). Within the TTM group eight patients were treated with normothermia after TBI and 35 patients were treated with hypothermia. A logistic regression predicting in hospital mortality with age, GCS, and TM demonstrated that GCS (Beta = 0.572, P < 0.01) and age (Beta = -0.029) but not temperature modulation (Beta = 0.797, ns) were significant predictors of in-hospital mortality [χ(2) (3) = 22.27, P < 0.01] A multiple regression predicting number of complications demonstrated that receiving TTM was the main contributor and was associated with a higher number of pulmonary complications (t = -3.425, P = 0.001). CONCLUSION: Exposure to TTM is associated with an increase in pulmonary complications. These findings support more attention to these complications in studies of TTM in TBI patients.

Consensus statement from the 2014 International Microdialysis Forum.

Microdialysis enables the chemistry of the extracellular interstitial space to be monitored. Use of this technique in patients with acute brain injury has increased our understanding of the pathophysiology of several acute neurological disorders. In 2004, a consensus document on the clinical application of cerebral microdialysis was published. Since then, there have been significant advances in the clinical use of microdialysis in neurocritical care. The objective of this review is to report on the International Microdialysis Forum held in Cambridge, UK, in April 2014 and to produce a revised and updated consensus statement about its clinical use including technique, data interpretation, relationship with outcome, role in guiding therapy in neurocritical care and research applications.

Intracranial pressure monitoring and management of intracranial hypertension.

Intracranial pressure (ICP) monitoring is considered the standard of care in the majority of neurosurgical centers in North America and Europe. ICP is a reflection of the relationship between alterations in craniospinal volume and the ability of the craniospinal axis to accommodate added volume. ICP cannot be reliably estimated from any specific clinical feature or CT finding and must be directly measured. This review describes methods of monitoring ICP and how monitoring technique can provide additional information and provides key points regarding the treatment of intracranial hypertension in the neuro-ICU.

Surfers' myelopathy: a case series of 19 novice surfers with nontraumatic myelopathy.

OBJECTIVE: We report the clinical characteristics of the largest series of nontraumatic spinal cord injury in novice surfers (surfers' myelopathy). METHODS: A retrospective review of the electronic medical record was performed in patients with nontraumatic spinal cord injury associated with surfing identified upon admission to the largest tertiary referral hospital in Hawaii from June 2002 to November 2011. Classification by the American Spinal Injury Association Impairment Scale (AIS) was performed upon admission and at follow-up. Clinical management, including blood pressure measurements and optimization, use of corticosteroids, and diagnostic evaluations, were reviewed. Follow-up information was obtained by clinic visits, telephone interviews, and electronic mail up to 3 years after injury. RESULTS: In 19 patients (14 male) aged 15-46 years, all patients complained of sudden onset of low back pain while surfing, followed by bilateral leg numbness and paralysis progressing over 10-60 minutes. All patients were novice surfers; 17 of 19 were surfing for the first time. On T2-weighted MRI, all patients had hyperintensity from the lower thoracic spinal cord to the conus medullaris. Six of 10 patients who underwent spinal diffusion-weighted MRI showed restricted diffusion in this region. Patients presenting with worse AIS scores had minimal improvement at follow-up. Blood pressure, corticosteroids, and imaging results were not associated with severity of neurologic deficits at follow-up. CONCLUSIONS: Although the cause of surfers' myelopathy is unclear, the rapid onset and presence of restricted diffusion suggest ischemic injury. Admission severity appears to be most predictive of neurologic outcome.

Emergency neurological life support: spinal cord compression (SCC).

Acute spinal cord compression (SCC) is the most serious of the diseases of the cord and should be accorded special attention in neurocritical care. Patients with SCC have a combination of motor and sensory dysfunction that has a distribution referable to one, or a few contiguous, spinal levels. Bowel and bladder dysfunction and neck or back pain are usually part of the clinical presentation but are not uniformly present. Because interventions are time-sensitive, the recognition and treatment of SCC was chosen as an ENLS protocol.

Intensive versus conventional insulin therapy in critically ill neurologic patients.

BACKGROUND: Previous studies of glycemic control in non-neurologic ICU patients have shown conflicting results. The purpose was to investigate whether intensive insulin therapy (IIT) to keep blood glucose levels from 80 to 110 mg/dl or conventional treatment to keep levels less than 151 mg/dl was associated with a reduction of mortality and improved functional outcome in critically ill neurologic patients. METHODS: Within 24 h of ICU admission, mechanically ventilated adult neurologic patients were enrolled after written informed consent and randomized to intensive or conventional control of blood glucose levels with insulin. Primary outcome measure was death within 3 months. Secondary outcome measures included 90-day modified Rankin scale (mRS) score, ICU, and hospital LOS. RESULTS: 81 patients were enrolled. The proportion of deaths was higher among IIT patients but this was not statistically significant (36 vs. 25%, P = 0.34). When good versus poor outcome at 3 months was dichotomized to mRS score 0-2 versus 3-6, respectively, there was no difference in outcome between the two groups (76.2 vs. 75% had a poor 3-month outcome, P = 1.0). There was also no difference in ICU or hospital LOS. Hypoglycemia (<60 mg/dl) and severe hypoglycemia (<40 mg/dl) were more common in the intensive arm (48 vs. 11%, P = 0.0006; and 4 vs. 0%, P = 0.5, respectively). CONCLUSION: There was no benefit to IIT in this small critically ill neurologic population. This is the first glycemic control study to specifically examine both critically ill stroke and traumatic brain injury (TBI) patients and functional outcome. Given these results, IIT cannot be recommended over conventional control.