Rapid disappearance of acute subdural hematoma due to abrogated hyper-fibrinolytic activity by tranexamic acid: Case report

RATIONALE

Acute subdural hematoma (ASDH) occurs after tearing of bridging veins within the dura resulting in the accumulation of blood between the arachnoid and dura layers within 72 hours after traumatic head injury. Also, antigen fibrin D-dimer (DD) is the principal enzymatic degradation product of cross-linked fibrin by plasmin. We observed that early tranexamic acid (TXA) treatment resolved hyper-fibrinolysis and rapid disappearance ASDH.

PATIENTS CONCERNS

A 48-year-old female presented with unconsciousness for 2 hours after head trauma. Her Glasgow Coma Scale score was >8 points.

DIAGNOSIS

Computed tomography scan established ASDH with midline shift and brainstem compression and surgery was scheduled. Also, laboratory results indicated high DD spike of 34,820 μg/L and a reduction in plasma fibrinogen 1 hour after the injury.

INTERVENTION

She was treated with intravenous TXA immediately after admission.

OUTCOMES

Her DD spike decreased remarkably in 48 hours with associated rapid disappearance of ASDH thereby averting surgical intervention. She recovered fully with no long-term complications.

LESSONS

Historically, hyper-fibrinolysis is associated with poor outcome in head trauma. However, early initiation of TXA which is noninvasive treatment modality for ASDH could avert surgery and reduce cost, anesthesia, and other complications associated with surgery.

The Effect of the COVID-19 Pandemic and Lockdown on Operative Traumatic Brain Injury in Northern Virginia

INTRODUCTION

COVID-19 is a disease that causes flu-like symptoms and difficulty breathing. Emerging in 2019, the COVID-19 pandemic has affected the entire world through restrictions and lockdowns. Multiple studies have compared the effects of COVID-19 on different types of head trauma, with each one producing different results. The goal of this study was to use state and hospital data to determine whether the COVID-19 pandemic had a significant impact on surgeries for traumatic brain injury (TBI).

METHODS

Public state data on COVID-19 incidence, sourced from the Virginia Department of Health, was compared to hospital data of 352 patients receiving surgeries for TBI from a single major level-one trauma hospital in Northern Virginia. We used data from the three years before COVID-19 and the two years during the pandemic, using t-tests and Pearson correlation to analyze the data. This is a retrospective case review study on the number and age of patients receiving TBI surgery from March 2017 through February 2022 at Inova Fairfax Hospital in Northern Virginia to determine the impact of the COVID-19 pandemic on these factors.

RESULTS

When comparing the data, there was a 60% reduction in cases of operative TBI during the peak months of COVID-19 compared to the same months in previous years (p<0.005). Comparing data on the number of Virginia and Northern Virginia COVID-19 cases and data on the age of individuals undergoing TBI surgery four weeks later showed a statistically significant negative correlation (p<0.05) in which the average age of individuals undergoing TBI surgery was lower in the four-week block following a four-week block of increased COVID-19 incidence.

CONCLUSION

Our findings indicate a correlation between the period of decreased activity from COVID-19 restrictions in Virginia and a decline in both the number of TBI surgeries and the age of individuals undergoing these surgeries.

A Swine Model of Neural Circuit Electromagnetic Fields: Effects of Immediate Electromagnetic Field Stimulation on Cortical Injury

Background Neurologic diseases have profound disability, mortality, and socioeconomic effects worldwide. Treatment of these disorders varies but is largely limited to unique factors associated with neural physiology. Early studies have evaluated alterations in electromagnetic fields (EMF) due to neural disorders with subsequent modulation of EMF as a potential treatment modality. Swine models have begun to be evaluated as translational models in this effect. Methods EMF measurements of a Yucatan miniswine were recorded using proprietary non-contact, non-invasive induction sensors with a dual layer Mu-metal and interlaced copper mesh helmet. The swine then underwent controlled cortical impact (CCI) to simulate traumatic brain injury (TBI). Twenty minutes post-injury after surgical wound closure, the swine underwent targeted EMF signal modulation using a signal generator to stimulate the swine's injured cortical circuit using a sinusoidal wave individualized at 2.5 Hz with a 500mV positive offset at 1V. After 10 days of stimulation, settings were modified to another individualized frequency of 5.5 Hz, 500mV positive offset and 1V for stimulation. Behavioral patterns in swine were evaluated, and EMF measurements were recorded daily prior to, during, and after stimulation. Artificial intelligence (AI) models evaluated patterns in EMF signals. Histology of the stimulated swine cortex was evaluated using hematoxylin and eosin staining and pentachrome staining and compared to a control swine without stimulation and a swine that had received stimulation two days post-injury in a delayed fashion. Serial serum specimens and tissue at the time of euthanasia were obtained for assessment of neuron-specific enolase (NSE) concentration. Results Pre-operative and post-stimulation measurements demonstrated differences in patterns and activity early on. There was an identified peak at 1.6Hz, not frequently seen pre-operatively. There were convergent frequencies in both data sets at 10.5 Hz and 3.9 Hz. Plateaus and decreased variability of changes in slope were identified early in the post-injury phase. AI modeling identified early similarities in pre-operative and post-stimulation measurements through the patterns of peaks with similarities on postoperative day 10 and similarities in the valleys on postoperative day 17. Histologic specimens identified increased degrees of apoptosis and cellular death in the non-stimulated control compared to the stimulated swine. Similarly, the immediately stimulated swine had less apoptosis and increased histologic viability at the site of injury compared to the two-day delayed stimulation swine. There were increased levels of NSE noted in the stimulated swine at the site of injury compared to non-injured sites and the control swine. Conclusions Cortical function was appropriately measured through induction sensors and shielding in the form of a helmet and electromagnetic field channels. Early stimulation resulted in the early and durable recovery of neuronal circuit-driven electromagnetic field patterns. Histology identified increased viability of neurons with fewer apoptotic neurons and glial cells in stimulated swine with early stimulation identifying the best effect compared to a non-stimulated subject. This recovery identifies change and recovery at the circuit, cellular, and subcellular levels that potentiate the need for further study of EMF modulation as a treatment modality in neurological disorders.

Critical Care Experience With Clinical Cerebral Autoregulation Testing in Adults With Traumatic Brain Injury

BACKGROUND

To describe the setting, feasibility, and safety of static cerebral autoregulation testing in critically injured adults with traumatic brain injury (TBI).  Methods: We reviewed static autoregulation testing using transcranial Doppler (TCD) ultrasound in patients > 18 years with TBI ICD codes between January 1, 2014, and December 31, 2021. Adverse events during testing were defined as systemic hypertension (systolic blood pressure (SBP>180 mmHg), bradycardia (HR<40 bpm), and high ICP (>30 mmHg). Impaired and absent cerebral autoregulation was defined as an autoregulatory index (ARI) <0.4 and ARI 0, respectively. We characterized prescribed changes in intracranial pressure (ICP) and cerebral perfusion pressure (CPP) targets by autoregulation testing results.  Results: A total of 135 patients, median age 31 (interquartile range (IQR) 24, 43) years, 71.9% male, admission Glasgow coma scale (GCS) score 3 (IQR 3, 5.5), and 70.9% with subdural hematoma from severe (GCS 3-8; 133 (98.5%)) and moderate (GCS 9-12; 2 (1.5%)) TBI, underwent 309 attempted testing. All patients were mechanically ventilated and had ICP monitoring; 246 (80%) had brain tissue oxygen monitoring, and 68 (22%) had an external ventricular drain. The median number of autoregulation tests was two (range 1-3) tests/patient, and the median admission to the first test time was two days (IQR 1, 3). Of 55 (17.8%) tests not completed, systemic hypertension (32, 10.4%), intracranial hypertension (10, 3.2%), and bradycardia (3, 0.9%) were transient. Fifty-three (51%) of the first (n=104) autoregulation tests showed impaired/absent cerebral autoregulation. Impaired/absent autoregulation results at the first test were associated with repeat cerebral autoregulation testing (RR 2.25, 95% CI [1.40-3.60], p=0.0007) than intact cerebral autoregulation results. Pre-testing cerebral hemodynamic targets were maintained (n=131; 86.8%) when cerebral autoregulation was impaired (n=151; RR 1.49, 95% CI [1.25-1.77], p<0.0001). However, 15 (9.9%) test results led to higher ICP targets (from 20 mmHg to 25 mmHg), 5 (3.3%) results led to an increase in CPP target (from 60 mmHg to 70 mmHg), and five out of 131 (3.8%) patients underwent decompressive craniectomy and placement of an external ventricular drain. Intact cerebral autoregulation results (n=43/103, 41.7%) were associated with a change in ICP targets from 20 mmHg to 25 mmHg (RR 3.15, 95% CI [1.97-5.03], p<0.0001).  Conclusions: Static cerebral autoregulation testing was feasible, safe, and useful in individualizing the care of patients with moderate-severe TBI receiving multimodal neuromonitoring. Testing results guided future testing, cerebral hemodynamic targets, and procedural decisions. Impaired cerebral autoregulation was very common.

Persistent Neurological, Dissociative, and Amnestic Symptoms Following a Mild Traumatic Brain Injury in an Adolescent: A Complex Case of Conversion Disorder

The diagnosis of conversion disorder may be given to patients with unexplained neurological symptoms after the exclusion of medical and organic etiologies, suggesting a psychiatric etiology. It requires a thorough examination of all contributing factors across the biopsychosocial model. With a variety of possible presentations, the evaluation and treatment of conversion disorder should reflect its complexity. This case report describes a case of conversion disorder complicated by mild traumatic brain injury and acute psychological re-traumatization in an adolescent with social anxiety and focuses on the connection between symptoms of conversion and dissociation with trauma and memory to form an understanding of the unique presentation and treatment of this condition.

A Swine Model of Traumatic Brain Injury: Effects of Neuronally Generated Electromagnetic Fields and Electromagnetic Field Stimulation on Traumatic Brain Injury-Related Changes

Background and objective Traumatic brain injury (TBI) has been associated with aberrations in neural circuitry attributable to the pathology resulting in electromagnetic field (EMF) changes. These changes have been evaluated in a variety of settings including through novel induction sensors with an ultra-portable shielded helmet and EMF channels with differences identified by comparing pre-injury and post-injury states. Modulation of the EMF has undergone cursory evaluation in neurologic conditions but has not yet been fully evaluated for clinical effects in treatment. Target EMF stimulation using EMF-related changes preoperatively to postoperatively has not yet been attempted and has not been completed using induction sensor technology. Our objectives in this study were twofold: we wanted to test the hypothesis that targeted stimulation using an EMF signal generator and stimulator to abnormal thresholds identified by real-time measurement of EMFs may enable early resolution of EMF changes and treatment of the TBI as modeled through controlled cortical impact (CCI); we also aimed to assess the feasibility of attempting this using real-time measurements with an EMF shielded helmet with EMF channels and non-contact, non-invasive induction sensors with attached EMF transmitters in real-time. Methods A singular Yucatan miniswine was obtained and baseline EMF recordings were obtained. A CCI of TBI and postoperative assessment of cortical EMF in a non-invasive, non-contact fashion were completed. Alterations in EMF were evaluated and EMF stimulation using those abnormal frequencies was completed using multiple treatments involving three minutes of EMF stimulation at abnormal frequencies. Stimulation thresholds of 2.5 Hz, 3.5 Hz, and 5.5 Hz with 1 V signal intensity were evaluated using sinusoidal waves. Additionally, stimulation thresholds using differing offsets to the sine wave at -500 mV, 0 mV, and 500 mv were assessed. Daily EMF and post-stimulation EMF measurements were recorded. EMF patterns were then assessed using an artificial intelligence (AI) model. Results AI modeling appropriately identified differences in EMF signal in pre-injury, post-injury, and post-stimulation states. EMF stimulation using a positive offset of 500 mV appeared to have maximal beneficial effects in return to baseline. Similarly targeted stimulation using thresholds of 2.5 Hz and 5.5 Hz with a positive 500 mV offset at 1 V allowed for recovery of EMF patterns post-injury towards patterns seen in baseline EMF measurements on stimulation day seven (postoperative day 17). Conclusion Stimulation of neural circuits with targeted EMF in a sinusoidal pattern with targeted thresholds after measurement with induction sensors with shielding isolated to a Mu-metal and copper mesh helmet and EMF channels is efficacious in promoting neuronal circuit recovery to preoperative baselines in the TBI miniswine model. Similarly, our findings confirm the appropriateness of this translational model in the evaluation of brain neuronal circuit EMF and that preoperative and post-trauma differences can be appropriately assessed with this technology.

A Swine Model of Changes in the Neuronal Electromagnetic Field After Traumatic Brain Injury: A Pilot Study

Background Traumatic brain injury (TBI) is a global cause of disability and mortality. Treatment depends on mitigation of secondary injury resulting in axonal injury, necrosis, brain dysfunction, and disruption of electrical and chemical signaling in neural circuits. To better understand TBI, translational models are required to study physiology, diagnostics, and treatments in homologous species, such as swine. Electromagnetic fields (EMFs) from altered neural circuits can be measured and historically have been reliant on expensive shielding and supercooling in magnetoencephalography. Using proprietary induction sensors, it has been found that a non-invasive, non-contact approach with an engineered Mu-metal and copper mesh-shielded helmet effectively measures EMFs. This has not yet been investigated in swine models. We wished to evaluate the efficacy of this technology to assess TBI-dependent EMF changes in swine to describe the efficacy of these sensors and this model using a gravity-dependent controlled cortical impact (CCI). Methods A Yucatan miniswine was evaluated using non-contact, non-invasive proprietary induction sensors with an engineered dual-layer Mu-metal and interlaced copper mesh helmet with sensors within EMF channels connected to a helmet. Swine EMF recordings were obtained prior to induced gravity-dependent CCI followed by post-TBI measurements. Behavioral changes and changes in EMF measurements were assessed. EMF measurements were evaluated with an artificial intelligence (AI) model. Results Differences between room "noise" EMF measurements and pre-TBI swine electromagnetic field measurements were identified. Morphological characteristics between pre-injury and post-injury measurements were noted. AI modeling differentiated pre-injury and post-injury patterns in the swine EMF. Frequently identified frequencies seen post-injury were peaks at 2.5 Hz and 6.5 Hz and a valley at 11 Hz. The AI model identified less changes in the slope and thus decreased variation of EMF measurements post-TBI between 4.5 Hz and 7 Hz. Conclusions For the first time, it was identified that cortical function in a swine can be appropriately measured using novel induction sensors and shielding isolated to a helmet and EMF channels. The swine model can be appropriately differentiated from the external noise signal with identifiably different pre-injury and post-injury EMFs. Patterns can be recognized within the post-injury EMF due to altered neural circuits that can be measured using these sensors continuously, non-invasively, and in real time.

Depression in Patients With Intracranial Hemorrhage Secondary to Traumatic Brain Injury

This article discusses the prevalence of depression in patients with intracranial hemorrhage (ICH) and the relationship of selective serotonin reuptake inhibitor (SSRI) use with bleeding risk. A detailed account of the patient's psychiatric history and current hospital admission is also provided. This article then further explores the pathophysiological mechanisms that contribute to depression in ICH patients, the effect of SSRIs on outcomes in patients with ICH, and ways to treat depression in ICH patients. Based on the literature, the conclusion is that practitioners should avoid SSRIs in ICH patients with certain genetic markers and treat depression as seriously as one would treat a physical ailment. Ultimately, more research is necessary to explore how to treat depression in this patient population.

Cisternostomy as a Surgical Treatment for Traumatic Brain Injury-Related Prolonged and Delayed Intracranial Pressure Elevation: A Case Report

Traumatic brain injury (TBI) can be classified into primary, due to the effect of the initial trauma, or secondary, due to increased intracranial pressure (ICP). Increased ICP may cause brain herniation and also decreases cerebral blood perfusion leading to ischemia. Recently, a few studies showed that cisternostomy with decompressive craniectomy (DC) has better outcomes than DC alone in patients with TBI. This can be explained by the recent advances indicating that cisternal cerebrospinal fluid (CSF) communicates with cerebral interstitial fluid (IF) through Virchow-Robin spaces. Theoretically, opening cisterns to atmospheric pressure may induce IF drainage and subsequently decrease ICP. A 55-year-old man presented to the emergency department with subdural hematomas, hemorrhagic contusions, and subarachnoid hemorrhage after falling off a moving truck. ICP elevation was refractory despite increased sedation, initiation of paralysis with Cisatracurium, esophageal cooling, multiple doses of 23.4 % saline and mannitol, and DC. Lumbar drain (LD) placement was performed with beneficial results. Unfortunately, the LD stopped functioning multiple times and each time this occurred, he developed increased ventricular size with elevated ICP. The patient underwent cisternostomy and lamina terminalis fenestration. No further increased ICPs were observed after cisternostomy at a one-month follow-up. Cisternostomy is a potential surgical treatment for patients with TBI-related prolonged ICP elevation.

Prehospital Electroencephalography to Detect Traumatic Brain Injury during Helicopter Transport: A Pilot Observational Cohort Study

OBJECTIVE

Early recognition of traumatic brain injury (TBI) is important to facilitate time-sensitive care. Electroencephalography (EEG) can identify TBI, but feasibility of EEG has not been evaluated in prehospital settings. We tested the feasibility of obtaining single-channel EEG during air medical transport after trauma. We measured association between quantitative EEG features, early blood biomarkers, and abnormalities on head computerized tomography (CT).

METHODS

We performed a pilot prospective, observational study enrolling consecutive patients transported by critical care air ambulance from the scene of trauma to a Level I trauma center. During transport, prehospital clinicians placed a sensor on the patient's forehead to record EEG. We reviewed EEG waveforms and selected 90 seconds of recording for quantitative analysis. EEG data processing included fast Fourier transform to summarize component frequency power in the delta (0-4 Hz), theta (4-8 Hz), and alpha (8-13 Hz) ranges. We collected blood samples on day 1 and day 3 post-injury and measured plasma levels of two brain injury biomarkers (ubiquitin C-terminal hydrolase L1 [UCH-L1] and glial fibrillary acidic protein [GFAP]). We compared predictors between individuals with and without CT-positive TBI findings.

RESULTS

Forty subjects were enrolled, with EEG recordings successfully obtained in 34 (85%). Reasons for failure included uncharged battery (n = 5) and user error (n = 1). Data were lost in three cases. Of 31 subjects with data, interpretable EEG signal was recorded in 26 (84%). Mean age was 48 (SD 16) years, 79% were male, and 50% suffered motor vehicle crashes. Eight subjects (24%) had CT-positive TBI. Subjects with and without CT-positive TBI had similar median delta power, alpha power, and theta power. UCH-L1 and GFAP plasma levels did not differ across groups. Delta power inversely correlated with UCH-L1 day 1 plasma concentration (r = -0.60, p = 0.03).

CONCLUSIONS

Prehospital EEG acquisition is feasible during air transport after trauma.

A Survey of Traumatic Brain Injuries from Road Traffic Collisions in a Lower Middle-Income Country

The burden of traumatic brain injury (TBI) from road traffic collisions (RTCs) is great in low-and middle-income countries (LMICs) due to shortfalls in preventative measures, and the lack of relevant, accurate data collection. To address this gap, we sought to study the epidemiology of TBI from RTCs in two LMIC neurosurgical centres in order to identify factors amenable to preventative strategies. A prospective survey of all adult and paediatric cases of TBI from RTCs admitted to Northwest General Hospital (NWGH) and Hayatabad Medical Complex (HMC) over a four-week period was carried out. Data on patient demographics, risk factors, injury details, pre-hospitalisation details, admission details and post-acute care was collected and analysed. A total of 68 patients were included in the study. 18 (26%) of the patients were male and in the 30 to 39 age group. Fifty-two percent were two-wheeler riders and/or passengers. 51 (75%) of the RTCs occurred between 12 noon and 12 midnight and in rural areas (66.2%). The most commonly documented risk factor that led to the RTC was speeding (35.3%). Pre-hospital care was either absent or undocumented. Up to two-thirds of patients were not direct transfers, and most were transported in private vehicles (48.5%) arriving later than an hour after injury (94.1%). Less than half with documented disabilities were referred for rehabilitation (38.5%). There are still gaps in the prevention of TBI from RTCs and in relevant data collection. Data collection systems must be strengthened, and further exploratory research carried out in order to improve the prevention of TBI from RTCs.

Usability and validity of a virtual reality cognitive assessment tool for pediatric traumatic brain injury

PURPOSE/OBJECTIVE

Deficits in executive functions are prevalent among children with traumatic brain injury (TBI). Assessing cognitive impairment is critical for evaluating and monitoring recovery. The present article reports a pilot study to evaluate the preliminary usability and validity of a virtual reality cognitive assessment tool (VR-CAT) specifically designed for children with TBI.

RESEARCH METHOD/DESIGN

A total of 54 children, 24 with TBI and 30 with orthopedic injury, participated in a cross-sectional cohort study at a Level-1 trauma center. The VR-CAT was evaluated in terms of user experience as well as preliminary psychometric properties including test-retest reliability, face validity, concurrent validity with two standard executive function assessment tools, and utility in distinguishing the TBI and orthopedic injury groups.

RESULTS

Children in both groups reported high levels of usability (i.e., enjoyment and motivation). The VR-CAT composite and scores on tests of inhibitory control and working memory demonstrated modest test-retest reliability across two independent assessment visits, as well as acceptable face validity, modest concurrent validity, and clinical utility.

CONCLUSIONS/IMPLICATIONS

The present study is among the first to evaluate the applicability of an immersive VR-CAT in children with TBI. The findings support high usability, adequate psychometric properties, and satisfactory clinical utility of the VR-CAT, suggesting it is a promising tool for assessing executive functions in this vulnerable population. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Unusual Presentation of Diffuse Axonal Injury: A Case Report

Diffuse axonal injury (DAI) is the microscopic axonal injury in the brain's neural pathways, corpus callosum, and brainstem, which has been linked to a major increase in morbidity and mortality. Patients present acutely with no lucid interval, abnormal pupil response, and decerebrate or decorticate posture. In this case report, we report on an 11-year-old girl who was agitated, crying, vomiting, had one episode of seizure, and had poor communication as a result of a high-risk mechanism side-impact motor vehicle collision (MVC).

Blood Pressure Control in Traumatic Subdural Hematomas

Background There is debate over optimal systolic blood pressure (SBP) after traumatic subdural hematoma. Increased SBP has the benefit of increasing cerebral perfusion pressure and limiting the detrimental secondary effects of traumatic brain injury but poses a risk of hematoma expansion. While prior studies have shown that SBP<90mmHg is associated with worsened morbidity and mortality in subdural hematoma patients, clinical guidelines and expert opinion have differing initial SBP goals. The aim of this study is to leverage a large database to determine the effects of two such goals, namely SBP 100-150mmHg versus SBP<180mmHg in this patient population. Methods A de-identified database network (TriNetX Research Network) was used to retrospectively query all patients with a first instance diagnosis of acute traumatic SDH, who also had a recorded GCS, with maintenance of SBP 100-150 within the first 24 hours (cohort 1) versus patients with an SBP<180 (cohort 2). Data came from 68 health care organizations (HCOs) with a total of 105,897,964 patients on 9/1/2022. The primary outcome of interest was mortality within 30 days. Secondary outcomes include gastrostomy tube placement, craniotomy/craniectomy/burr hole drainage, venous thromboembolism, ischemic stroke, myocardial infarction, seizure, falls, cardiac arrest, and acute kidney injury within 30 days. Cohorts were propensity-score matched for confounders. Results After propensity score matching, 1,243 patients were identified in each cohort. Age at index was 57.97+/-23.21 years and 58.28+/-22.35 years for cohorts 1 and 2, respectively. Mortality was seen in 243 patients (19.756%) vs. 209 (16.992%) (OR 1.203, 95% CI (0.98,1.476), p=0.0767) in cohorts 1 and 2, respectively. There was no statistical difference in secondary outcomes. Conclusion The results of this study demonstrate that the primary outcome of mortality at 30 days is not statistically different in acute traumatic SDH patients, whether their SBP is kept at 100-150 or below 180. Likewise, it shows no statistical difference in the subsequent incidence of gastrostomy tube placement, craniotomy/craniectomy/burr holes, venous thromboembolism, ischemic stroke, myocardial infarction, seizure, falls, or acute kidney injury.

A Case of Possible Chronic Traumatic Encephalopathy and Alzheimer's Disease in an Ex-Football Player

INTRODUCTION

Chronic traumatic encephalopathy (CTE) is a debilitating neurodegenerative disease, which is often the sequelae of repetitive head trauma. Although the definitive diagnosis of CTE is made postmortem, there are proposed clinical algorithms aimed at identifying characteristic features of CTE, based on a combination of clinical history, serum, cerebrospinal fluid and neuroimaging biomarkers. There are promising new advances in positron emission tomography neuroimaging, including tau specific ligands, which will potentially provide a robust assessment as well as an exploratory tool of the disease semiology and progression.

CASE REPORT

Here is a unique case of an ex-football player, who suffered multiple prior traumatic brain injuries throughout his career, and presented to our clinic with significant episodic memory, visuospatial and executive functioning deficits, as well as comorbid mood and behavioral changes in the absence of prior psychiatric history or substance use. His clinical presentation and biomarkers were consistent with a suspected diagnosis of CTE comorbid with Alzheimer disease, which comprises a significant portion of overall CTE cases.

CONCLUSION

This case report presents a patient with a subtle case of dementia, which could be easily mistaken for behavioral variant frontotemporal dementia or primary progressive aphasia. This in turn highlights the importance of detailed longitudinal history taking, as well as rigorous biomarker studies.

Protocol for a Multicenter, Prospective, Observational Pilot Study on the Implementation of Resource-Stratified Algorithms for the Treatment of Severe Traumatic Brain Injury Across Four Treatment Phases: Prehospital, Emergency Department, Neurosurgery, and Intensive Care Unit

BACKGROUND

Severe traumatic brain injury (sTBI) is a public health issue with great disparity among low- and middle-income countries where the implementation of evidence-based guidelines is challenging because resources are often unavailable. A consensus process including experts in the prehospital, emergency department, neurosurgery, and intensive care unit took place in Colombia to develop a set of stratified protocols called BOOTStraP, targeting resource-poor environments, but it has not been systematically implemented and tested.

OBJECTIVE

To identify the facilitators of, and barriers to, collecting data about patients with sTBI and to implement a stratified protocol across the treatment phases of prehospital, emergency department, neurosurgery, and intensive care unit in low-resource settings. We also aim to identify a possible association between adherence to these protocols and outcomes for these patients.

METHODS

A prospective, observational, before and after, pilot study will be performed in three phases as follows: before implementation, implementation, and after implementation. The BOOTStraP protocols will be implemented in three Colombian centers.

EXPECTED OUTCOMES

We expect to find numerous barriers during the implementation phase. We also expect moderate adherence to the protocols. However, we expect to find an increase in the survival rate to hospital discharge and an improvement in neurological outcomes at discharge.

DISCUSSION

This pilot study will serve as a first step to identify variables that are critical to successful implementation, to be considered for the design of a future large-scale international study to measure the effectiveness of resource-based protocols and to improve outcomes from sTBI.

Predictors for Withdrawal of Life-Sustaining Therapies in Patients With Traumatic Brain Injury: A Retrospective Trauma Quality Improvement Program Database Study

Many patients with severe traumatic brain injuries (TBIs) undergo withdrawal of life-sustaining therapies (WLSTs) or transition to comfort measures, but noninjury factors that influence this decision have not been well characterized. We hypothesized that WLST would be associated with institutional and geographic noninjury factors. All patients with a head Abbreviated Injury Scale score ≥3 were identified from 2016 Trauma Quality Improvement Program data. We analyzed factors that might be associated with WLST, including procedure type, age, sex, race, insurance, Glasgow Coma Scale score, mechanism of injury, geographic region, and institutional size and teaching status. Adjusted logistic regression was performed to examine factors associated with WLST. Sixty-nine thousand fifty-three patients were identified: 66% male, 77% with isolated TBI, and 7.8% had WLST. The median age was 56 years (34-73). A positive correlation was found between increasing age and WLST. Women were less likely to undergo WLST than men (odds ratio 0.91 [0.84-0.98]) and took more time to for WLST (3 vs 2 days, P < .001). African Americans underwent WLST at a significantly lower rate (odds ratio 0.66 [0.58-0.75]). Variations were also discovered based on US region, hospital characteristics, and neurosurgical procedures. WLST in severe TBI is independently associated with noninjury factors such as sex, age, race, hospital characteristics, and geographic region. The effect of noninjury factors on these decisions is poorly understood; further study of WLST patterns can aid health care providers in decision making for patients with severe TBI.

Repetitive Traumatic Brain Injury Among Older Adults

OBJECTIVE

To determine the incidence of and assess risk factors for repetitive traumatic brain injury (TBI) among older adults in the United States.

DESIGN

Retrospective cohort study.

SETTING

Administrative claims data obtained from the Centers for Medicare & Medicaid Services' Chronic Conditions Data Warehouse.

PARTICIPANTS

Individuals 65 years or older and diagnosed with TBI between July 2008 and September 2012 drawn from a 5% random sample of US Medicare beneficiaries.

MAIN MEASURES

Repetitive TBI was identified as a second TBI occurring at least 90 days after the first occurrence of TBI following an 18-month TBI-free period. We identified factors associated with repetitive TBI using a log-binomial model.

RESULTS

A total of 38 064 older Medicare beneficiaries experienced a TBI. Of these, 4562 (12%) beneficiaries sustained at least one subsequent TBI over up to 5 years of follow-up. The unadjusted incidence rate of repetitive TBI was 3022 (95% CI, 2935-3111) per 100 000 person-years. Epilepsy was the strongest predictor of repetitive TBI (relative risk [RR] = 1.44; 95% CI, 1.25-1.56), followed by Alzheimer disease and related dementias (RR = 1.32; 95% CI 1.20-1.45), and depression (RR = 1.30; 95% CI, 1.21-1.38).

CONCLUSIONS

Injury prevention and fall-reduction interventions could be targeted to identify groups of older adults at an increased risk of repetitive head injury. Future work should focus on injury-reduction initiatives to reduce the risk of repetitive TBI as well as assessment of outcomes related to repetitive TBI.

The Association Between Concussion History and Increased Symptom Severity Reporting Is Independent of Common Medical Comorbidities, Personality Factors, and Sleep Quality in Collegiate Athletes

OBJECTIVE

We investigated the degree to which the association between history of concussion with psychological distress and general symptom severity is independent of several factors commonly associated with elevated symptom severity. We also examined whether symptom severity endorsement was associated with concussion injury specifically or response to injury in general.

SETTING

Academic medical center.

PARTICIPANTS

Collegiate athletes ( N = 106; age: M = 21.37 ± 1.69 years; 33 female) were enrolled on the basis of strict medical/psychiatric exclusion criteria.

DESIGN

Cross-sectional single-visit study. Comprehensive assessment, including semistructured interviews to retrospectively diagnose the number of previous concussions, was completed. Single-predictor and stepwise regression models were fit to examine the predictive value of prior concussion and orthopedic injuries on symptom severity, both individually and controlling for confounding factors.

MAIN OUTCOME MEASURES

Psychological distress was operationalized as Brief Symptom Inventory-18 Global Severity Index (BSI-GSI) ratings; concussion-related symptom severity was measured using the Sport Concussion Assessment Tool.

RESULTS

Controlling for baseline factors associated with the symptom outcomes (agreeableness, neuroticism, negative emotionality, and sleep quality), concussion history was significantly associated with psychological distress ( B = 1.25 [0.55]; P = .025, Δ R2 = 0.034) and concussion-like symptom severity ( B = 0.22 [0.08]; P = .005, Δ R2 = 0.064) and accounted for a statistically significant amount of unique variance in symptom outcomes. Orthopedic injury history was not individually predictive of psychological distress ( B = -0.06 [0.53]; P = .905) or general symptom severity ( B = 0.06 [0.08]; P = .427) and did not explain the relationship between concussion history and symptom outcomes.

CONCLUSIONS

Concussion history is associated with subtle elevations in symptom severity in collegiate-aged athletes; this relationship is independent of medical, lifestyle (ie, sleep), and personality factors. Furthermore, this relationship is associated with brain injury (ie, concussion) and is not a general response to injury history.

Tranexamic acid is not inferior to placebo with respect to adverse events in suspected traumatic brain injury patients not in shock with a normal head computed tomography scan: A retrospective study of a randomized trial

BACKGROUND

A 2-g bolus of tranexamic acid (TXA) has been shown to reduce 28-day mortality in a randomized controlled trial. This study investigates whether out-of-hospital TXA use is associated with adverse events or unfavorable outcomes in suspected traumatic brain injury (TBI) when intracranial hemorrhage (ICH) is absent on initial computed tomography.

METHODS

This study used data from a 2015 to 2017, multicenter, randomized trial studying the effect of the following TXA doses on moderate to severe TBI: 2-g bolus, 1-g bolus plus 1-g infusion over 8 hours, and a placebo bolus with placebo infusion. Of the 966 participants enrolled, 395 with an initial computed tomography negative for ICH were included in this analysis. Fifteen adverse events (28-day incidence) were studied: myocardial infarction, deep vein thrombosis, seizure, pulmonary embolism, acute respiratory distress syndrome, cardiac failure, liver failure, renal failure, cerebrovascular accident, cardiac arrest, cerebral vasospasm, "any thromboembolism," hypernatremia, acute kidney injury, and infection. Other unfavorable outcomes analyzed include mortality at 28 days and 6 months, Glasgow Outcome Scale-Extended score of ≤4 at discharge and 6 months, intensive care unit-free days, ventilator-free days, hospital-free days, and combined unfavorable outcomes. In both study drug groups, the incidence of dichotomous outcomes and quantity of ordinal outcomes were compared with placebo.

RESULTS

No statistically significant increase in adverse events or unfavorable outcomes was found between either TXA dosing regimen and placebo. Demographics and injury scores were not statistically different other than two methods of injury, which were overrepresented in the 1-g TXA bolus plus 1-g TXA infusion.

CONCLUSION

Administration of either a 2-g TXA bolus or a 1-g TXA bolus plus 1-g TXA 8-hour infusion in suspected TBIs without ICH is not associated with increased adverse events or unfavorable outcomes. Because the out-of-hospital 2-g bolus is associated with a mortality benefit, it should be administered in suspected TBI.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level II.

Preinjury Health Status of Adults With Traumatic Brain Injury: A Preliminary Matched Case-Control Study

OBJECTIVE

To discern whether there is evidence that individuals who sustained a traumatic brain injury (TBI) had the greater odds of preexisting health conditions and/or poorer health behaviors than matched controls without TBI.

SETTING

Brain Injury Inpatient Rehabilitation Unit at Mount Sinai Hospital. Midlife in the United States (MIDUS) control data were collected via random-digit-dialing phone survey.

PARTICIPANTS

TBI cases were enrolled in the TBI Health Study and met at least 1 of the following 4 injury severity criteria: abnormal computed tomography scan; Glasgow Coma Scale score between 3 and 12; loss of consciousness greater than 30 minutes; or post-TBI amnesia longer than 24 hours. Sixty-two TBI cases and 171 matched MIDUS controls were included in the analyses; controls were excluded if they reported having a history of head injury.

DESIGN

Matched case-control study.

MAIN MEASURES

Self-reported measures of depression symptoms, chronic pain, health status, alcohol use, smoking status, abuse of controlled substances, physical activity, physical health composite score, and behavioral health composite score.

RESULTS

Pre-index injury depression was nearly 4 times higher in TBI cases than in matched controls (OR= 3.98, 95% CI, 1.71-9.27; P = .001). We found no significant differences in the odds of self-reporting 3 or more medical health conditions in year prior to index injury (OR = 1.52; 95% CI, 0.82-2.81; P = .183) or reporting more risky health behaviors (OR = 1.48; 95% CI; 0.75-2.91; P = .254]) in individuals with TBI than in controls.

CONCLUSION

These preliminary findings suggest that the odds of depression in the year prior to index injury far exceed those reported in matched controls. Further study in larger samples is required to better understand the relative odds of prior health problems in those who sustain a TBI, with a goal of elucidating the implications of preinjury health on post-TBI disease burden.

Prevalence of Concussion-Related Policies and Practices Among Public School Districts in the United States, 2012 and 2016

BACKGROUND

Beginning in 2009, there was an increase in the number of states with laws addressing 3 different components of youth sports-related concussion prevention and management: concussion education, removal from play, and medical clearance requirements before allowing an athlete to return to play. Schools are an important setting to implement policies and practices related to concussions, as many youth participate in organized sports through school venues.

OBJECTIVE

To examine whether the prevalence of concussion-related policies and practices adopted by school districts changed from 2012 to 2016.

METHODS

This study used nationally representative data from the 2012 and 2016 School Health Policies and Practices Study to examine whether the prevalence of 4 concussion-related policies and practices changed during 2012 and 2016 and whether comprehensive policies changed during the same time frame. Comprehensive policies were defined as those that address removal from play after injury, medical clearance before returning to play, and concussion-related educational materials and sessions for parents and student athletes.

RESULTS

Among school districts nationwide, the prevalence of each of the 4 concussion-related policies and practices significantly increased during 2012 and 2016. The prevalence of comprehensive policies significantly increased from 51.6% in 2012 to 66.7% in 2016. While these findings are promising, it is important to note that one-third of districts still lacked comprehensive policies in 2016 and only 71% of districts provided educational sessions in 2016.

CONCLUSIONS

The findings in this study highlight improvements in school districts nationwide in adopting concussion-related policies and practices. Policies such as requiring educational sessions allow parents and student athletes to learn about concussions and understand the importance of reporting a concussion or concussion symptoms.

Synergistic Role of Quantitative Diffusion Magnetic Resonance Imaging and Structural Magnetic Resonance Imaging in Predicting Outcomes After Traumatic Brain Injury

OBJECTIVE

This study aimed to assess if quantitative diffusion magnetic resonance imaging analysis would improve prognostication of individual patients with severe traumatic brain injury.

METHODS

We analyzed images of 30 healthy controls to extract normal fractional anisotropy ranges along 18 white-matter tracts. Then, we analyzed images of 33 patients, compared their fractional anisotropy values with normal ranges extracted from controls, and computed severity of injury to white-matter tracts. We also asked 2 neuroradiologists to rate severity of injury to different brain regions on fluid-attenuated inversion recovery and susceptibility-weighted imaging. Finally, we built 3 models: (1) fed with neuroradiologists' ratings, (2) fed with white-matter injury measures, and (3) fed with both input types.

RESULTS

The 3 models respectively predicted survival at 1 year with accuracies of 70%, 73%, and 88%. The accuracy with both input types was significantly better (P < 0.05).

CONCLUSIONS

Quantifying severity of injury to white-matter tracts complements qualitative imaging findings and improves outcome prediction in severe traumatic brain injury.

State-Level Numbers and Rates of Traumatic Brain Injury-Related Emergency Department Visits, Hospitalizations, and Deaths in 2014

OBJECTIVE

To provide state-level traumatic brain injury (TBI)-related emergency department (ED) visit, hospitalization, and death estimates for 2014.

SETTING AND PARTICIPANTS

The Centers for Disease Control and Prevention's Core Violence and Injury Prevention Program and State Injury Indicators participating states.

DESIGN

Cross-sectional.

MAIN MEASURES

Number and incidence rates of TBI-related ED visits, hospitalizations, and deaths in more than 30 states.

RESULTS

The rates of TBI-related ED visits in 2014 ranged from 381.1 per 100 000 (South Dakota) to 998.4 per 100 000 (Massachusetts). In 2014, Pennsylvania had the highest TBI-related hospitalization rate (98.9) and Ohio had the lowest (55.1). In 2014, the TBI-related death rate ranged from 9.1 per 100 000 (New Jersey) to 23.0 per 100 000 (Oklahoma).

CONCLUSION

The variations in TBI burden among states support the need for tailoring prevention efforts to state needs. Results of this analysis can serve as a baseline for these efforts.

Traumatic Brain Injury-Related Emergency Department Visits Among American Indian and Alaska Native Persons-National Patient Information Reporting System, 2005-2014

OBJECTIVE

The American Indian/Alaska Native (AI/AN) population has a disproportionately high rate of traumatic brain injuries (TBIs). However, there is little known about incidence and common mechanisms of injury among AI/AN persons who seek care in an Indian Health Service (IHS) or tribally managed facility.

METHODS

Using the IHS National Patient Information Reporting System, we assessed the incidence of TBI-related emergency department visits among AI/AN children and adults seen in IHS or tribally managed facilities over a 10-year period (2005-2014).

RESULTS

There were 44 918 TBI-related emergency department visits during the study period. Males and persons aged 18 to 34 years and 75 years and older had the highest rates of TBI-related emergency department visits. Unintentional falls and assaults contributed to the highest number and proportion of TBI-related emergency department visits. The number and age-adjusted rate of emergency department visits for TBI were highest among persons living in the Southwest and Northern Plains when compared with other IHS regions.

CONCLUSION

Thousands of AI/AN children and adults are seen each year in emergency departments for TBI and the numbers increased over the 10-year period examined. Evidence-based interventions to prevent TBI-related emergency department visits, such as programs to reduce the risk for older adult falls and assault, are warranted.

Electroconvulsive Therapy for Traumatic Brain Injury and Schizoaffective Disorder

Traumatic brain injury (TBI) is a source of disability and mortality with high rates of psychiatric disorders. Patients with comorbid TBI and psychiatric disorders may be safely treated with electroconvulsive therapy (ECT). In this case report, we present a 34-year-old man with the diagnosis of major neurocognitive disorder due to traumatic brain injury and schizoaffective disorder, bipolar type. He received an index course of 19 ECT treatments with clinical improvements in his psychosis, mood, and cognition. This case may support the utilization of ECT for patients with comorbid TBI and schizoaffective disorder.

Healthcare Providers' Self-Reported Pediatric Mild Traumatic Brain Injury Diagnosis, Prognosis, and Management Practices: Findings From the 2019 DocStyles Survey

OBJECTIVE

To assess adherence to 5 key recommendations in the Centers for Disease Control and Prevention evidence-based guideline on pediatric mild traumatic brain injury, this article presents results from the 2019 DocStyles survey.

STUDY DESIGN

Cross-sectional, web-based survey of 653 healthcare providers.

RESULTS

Most healthcare providers reported adhering to the recommendations regarding the use of computed tomography and providing education and reassurance to patients and their families. However, less than half reported routinely examining their patients with mild traumatic brain injury (mTBI) using age-appropriate, validated symptom scales, assessing for risk factors for prolonged recovery, and advising patients to return to noncontact, light aerobic activities within 2 to 3 days. Self-reported mTBI diagnosis, prognosis, and management practices varied by specialty. Only 3.8% of healthcare providers answered all 7 questions in a way that is most consistent with the 5 recommendations examined from the Centers for Disease Control and Prevention Pediatric mTBI Guideline.

CONCLUSION

This study highlights several important information gaps regarding pediatric mTBI diagnosis and management. Further efforts to improve adoption of guideline recommendations may be beneficial to ensure optimal outcomes for children following an mTBI.

Variation in neurosurgical intervention for severe traumatic brain injury: The challenge of measuring quality in trauma center verification

BACKGROUND

Intracranial pressure monitor (ICPm) procedure rates are a quality metric for American College of Surgeons trauma center verification. However, ICPm procedure rates may not accurately reflect the quality of care in TBI. We hypothesized that ICPm and craniotomy/craniectomy procedure rates for severe TBI vary across the United States by geography and institution.

METHODS

We identified all patients with a severe traumatic brain injury (head Abbreviated Injury Scale, ≥3) from the 2016 Trauma Quality Improvement Program data set. Patients who received surgical decompression or ICPm were identified via International Classification of Diseases codes. Hospital factors included neurosurgeon group size, geographic region, teaching status, and trauma center level. Two multiple logistic regression models were performed identifying factors associated with (1) craniotomy with or without ICPm or (2) ICPm alone. Data are presented as medians (interquartile range) and odds ratios (ORs) (95% confidence interval).

RESULTS

We identified 75,690 patients (66.4% male; age, 59 [36-77] years) with a median Injury Severity Score of 17 (11-25). Overall, 6.1% had surgical decompression, and 4.8% had ICPm placement. Logistic regression analysis showed that region of the country was significantly associated with procedure type: hospitals in the West were more likely to use ICPm (OR, 1.34 [1.20-1.50]), while Northeastern (OR, 0.80 [0.72-0.89]), Southern (OR, 0.84 [0.78-0.92]), and Western (OR, 0.88 [0.80-0.96]) hospitals were less likely to perform surgical decompression. Hospitals with small neurosurgeon groups (<3) were more likely to perform surgical intervention. Community hospitals are associated with higher odds of surgical decompression but lower odds of ICPm placement.

CONCLUSION

Both geographic differences and hospital characteristics are independent predictors for surgical intervention in severe traumatic brain injury. This suggests that nonpatient factors drive procedural decisions, indicating that ICPm rate is not an ideal quality metric for American College of Surgeons trauma center verification.

LEVEL OF EVIDENCE

Epidemiological, level III; Care management/Therapeutic level III.

Research Letter: Sleep Mediates the Association Between Prior Concussion and Depressive Symptoms

OBJECTIVE

To test sleep quality as one mechanistic pathway through which repeated concussion increases risk of depression later in life among former contact sport athletes.

SETTING

Multicenter study enrolled former American collegiate football players from 16 different National Collegiate Athletic Association member institutions.

PARTICIPANTS

Fifty-eight former American collegiate football players approximately 15 years following sport discontinuation.

DESIGN

Participants completed in-person evaluations including comprehensive semistructured interviews with detailed concussion history and sport history, as well as self-reported measures of depression symptom severity (Beck Depression Inventory-II) and sleep quality (Pittsburgh Sleep Quality Index). Years of football participation were included as a covariate. Mediation modeling examined the degree to which sleep quality accounted for the association between repeated concussion and depression symptoms.

RESULTS

Within the mediation model, concussion history significantly predicted sleep quality (B = 1.03; 95% CI, 0.37 to 1.65; P = .002) and sleep quality significantly predicted depressive symptom severity (controlling for the effects of concussion history; B = 0.15; 95% CI, 0.06 to 0.24; P = .001). The association between prior concussion and depressive symptom severity was fully mediated by sleep quality. With inclusion of the indirect effects, concussion history did not predict depressive symptom severity (direct effect: B = 0.14; 95% CI, -0.09 to 0.41; P = .249; indirect effect: 0.15; 95% CI, 0.03 to 0.29; P = .016).

CONCLUSIONS

Current findings raise the possibility that the greater risk of depression reported in those with a history of mTBI/concussion is mediated by sleep quality, a common sequela of mTBI. These findings highlight potential opportunities for prophylactic sleep-related intervention among individuals with multiple prior concussions to mitigate the risk of depression.

Dosimetric Evaluation Between the Conventional Volumetrically Modulated Arc Therapy (VMAT) Total Body Irradiation (TBI) and the Novel Simultaneous Integrated Total Marrow Approach (SIMBa) VMAT TBI

Purpose The purpose of this study was to assess the treatment planning feasibility of volumetrically modulated arc therapy total body irradiation (VMAT TBI) using a simultaneous integrated marrow and body approach (SIMBa). We also aimed to compare SIMBa TBI with the more conventional VMAT TBI approach using the entire body as the target. The goal of using an integrated approach like SIMBa is to balance the known clinical benefit of TBI with the toxicity decrease of Total Marrow Irradiation (TMI) using two prescription volumes. In anticipation of a clinical trial to investigate a novel conditioning regimen that uses SIMBa, our institution retrospectively analyzed the dosimetric differences between 20 clinical VMAT TBI which were re-planned using SIMBa. Methods Twenty patients who previously received conventional VMAT TBI at our institution with a dose of 12 Gy in six fractions were re-planned using SIMBa with a planning aim of delivering a uniform dose of 12 Gy to at least 90% of the PTV_BodyEval. The planning aims of SIMBa were to deliver a uniform dose of 12 Gy to at least 90% of the PTV_Marrow and 8 Gy to at least 90% of the PTV_TotalBody while limiting the mean lung dose to less than 8 Gy. The plans were normalized so that 100% of the PTV_Marrow received at least 90% of the dose with the PTV_TotalBody optimized to stay as close to 100% at 90% as possible. Results All 20 patient plans achieved 12 Gy/8 Gy to at least 90% of the PTV_Marrow and PTV_TotalBody, respectively, with max doses of <16 Gy (130%). As compared with the delivered TBI, the following reductions in mean dose were notable: small bowel 21.3±4.2%, lung 16.3±7.9%, heart 25.3±8.6%, and kidney 16.4±6.2%. Coverage of the sanctuary sites was maintained despite a significant reduction to sensitive organs at risk (OARs). Conclusion This study supports that VMAT TBI treatment planning with SIMBa is feasible. In this sample, SIMBa provided dosimetrically similar doses to marrow and sanctuary site doses as TBI while achieving lower doses to OARs. A clinical trial is needed to investigate the clinical implications of VMAT TBI with SIMBa.

Microglia as therapeutic targets after neurological injury: strategy for cell therapy

INTRODUCTION

Microglia is the resident tissue macrophages of the central nervous system. Prolonged microglial activation often occurs after traumatic brain injury and is associated with deteriorating neurocognitive outcomes. Resolution of microglial activation is associated with limited tissue loss and improved neurocognitive outcomes. Limiting the prolonged pro-inflammatory response and the associated secondary tissue injury provides the rationale and scientific premise for considering microglia as a therapeutic target.

AREAS COVERED

In this review, we discuss markers of microglial activation, such as immunophenotype and microglial response to injury, including cytokine/chemokine release, free radical formation, morphology, phagocytosis, and metabolic shifts. We compare the origin and role in neuroinflammation of microglia and monocytes/macrophages. We review potential therapeutic targets to shift microglial polarization. Finally, we review the effect of cell therapy on microglia.

EXPERT OPINION

Dysregulated microglial activation after neurologic injury, such as traumatic brain injury, can worsen tissue damage and functional outcomes. There are potential targets in microglia to attenuate this activation, such as proteins and molecules that regulate microglia polarization. Cellular therapeutics that limit, but do not eliminate, the inflammatory response have improved outcomes in animal models by reducing pro-inflammatory microglial activation via secondary signaling. These findings have been replicated in early phase clinical trials.

Costs of Nonfatal Traumatic Brain Injury in the United States, 2016

BACKGROUND

Traumatic brain injury (TBI) is a serious public health problem in the United States. Each year, TBIs substantially contribute to health care costs, which vary by severity. This is important to consider given the variability in recovery time by severity.

RESEARCH DESIGN

This study quantifies the annual incremental health care costs of nonfatal TBI in 2016 for the US population covered by a private health insurance, Medicaid, or Medicare health plan. This study uses MarketScan and defines severity with the abbreviated injury scale for the head and neck region. Nonfatal health care costs were compared by severity.

RESULTS

The estimated 2016 overall health care cost attributable to nonfatal TBI among MarketScan enrollees was $40.6 billion. Total estimated annual health care cost attributable to TBI for low severity TBIs during the first year postinjury were substantially higher than costs for middle and high severity TBIs among those with private health insurance and Medicaid.

CONCLUSIONS

This study presents economic burden estimates for TBI that underscore the importance of developing strategies to prevent TBIs, regardless of severity. Although middle and high severity TBIs were more costly at the individual level, low severity TBIs, and head injuries diagnosed as "head injury unspecified" resulted in higher total estimated annual health care costs attributable to TBI.

Differential effects of deployment and nondeployment mild TBI on neuropsychological outcomes

Objective: Mild traumatic brain injury (TBI) that occurs in a deployment environment is characteristically different from mild TBI that occurs outside of deployment. This study evaluated differential and interaction effects of deployment and nondeployment mild TBI on cognitive and behavioral health outcomes. Research Method: Combat veterans (N = 293) who passed performance-validity measures completed the Mid-Atlantic MIRECC Assessment of TBI (MMA-TBI), Clinician-Administered Posttraumatic Stress Disorder (PTSD) Scale (CAPS-5), a neuropsychological assessment battery, and self-report questionnaires. A 2 × 2 × 2 analysis of variance (ANOVA) was conducted to evaluate the main and interaction effects across mild TBI groups and PTSD diagnosis. Results: Deployment TBI was associated with poorer outcomes on several cognitive tests: Wechsler Adult Intelligence Scale, 4th edition (WAIS-IV); Working Memory Index (WMI; p = .018); Trail Making Test A (TMT-A; p < .001); and Trail Making Test B (TMT-B; p = .002). Deployment TBI and PTSD were also associated with increased PTSD, depressive, and neurobehavioral symptoms; pain interference; and poorer sleep quality. Nondeployment TBI had no effect on cognitive performance and was associated only with poorer sleep quality. PTSD had the strongest associations with symptom measures and deployment TBI with cognitive outcomes. There were no significant interaction effects after adjusting for multiple comparisons. Conclusions: Remote outcomes associated with mild deployment TBI are different from those associated with nondeployment mild TBI and are robust beyond PTSD. This suggests that the environment surrounding a TBI event influences cognitive and symptom sequelae. Veterans who experience mild TBI during deployment may report changes in cognition, but most will continue to function within the expected range. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Osteopathic Manipulative Treatment to Optimize the Glymphatic Environment in Severe Traumatic Brain Injury Measured With Optic Nerve Sheath Diameter, Intracranial Pressure Monitoring, and Neurological Pupil Index

Background

Traumatic brain injury (TBI) has a complex pathophysiology that has historically been poorly understood. New evidence on the pathophysiology, molecular biology, and diagnostic studies involved in TBI have shed new light on optimizing rehabilitation and recovery. The goal of this study was to assess the effect of osteopathic manipulative treatment (OMT) on peripheral and central glial lymphatics in patients with severe TBI, brain edema, and elevated intracranial pressure (ICP) by measuring changes in several parameters regularly used in management.

Methodology

This was a retrospective study at a level II trauma center that occurred in 2018. The study enrolled patients with TBI, increased ICP, or brain edema who had an external ventricular drain placed. Patients previously underwent a 51-minute treatment with OMT with an established protocol. Patients received 51 minutes of OMT to the head, neck, and peripheral lymphatics. The ICP, cerebrospinal fluid (CSF) drainage, optic nerve sheath diameter (ONSD) measured by ultrasonography, and Neurological Pupil Index (NPi) measured by pupillometer were recorded before, during, and after receiving OMT.

Results

A total of 11 patients were included in the study, and 21 points of data were collected from the patients meeting inclusion criteria who received OMT. There was a mean decrease in the ONSD of 0.62 mm from 6.24 mm to 5.62 mm (P = 0.0001). The mean increase in NPi was 0.18 (P = 0.01). The mean decrease in ICP was 3.33 mmHg (P= 0.0001). There was a significant decrease in CSF output after treatment (P = 0.0001). Each measurement of ICP, ONSD, and NPi demonstrated a decrease in overall CSF volume and pressure after OMT compared to CSF output and ICP prior to OMT.

Conclusions

This study demonstrates that OMT may help optimize glial lymphatic clearance of CSF and improve brain edema, interstitial waste product removal, NPi, ICP, CSF volume, and ONSD. A holistic approach including OMT may be considered to enhance management in TBI patients. As TBI is a spectrum of disease, utilizing similar techniques may be considered for all forms of TBI including concussions and other diseases with brain edema. The results of this study can better inform future trials to specifically study the effectiveness of OMT in post-concussive treatment and in those with mild-to-moderate TBI.

Worse Than Death: Survey of Public Perceptions of Disability Outcomes After Hypothetical Traumatic Brain Injury

OBJECTIVE

The aim of this study was to determine the health utility states of the most commonly used traumatic brain injury (TBI) clinical trial endpoint, the Extended Glasgow Outcome Scale (GOSE).

SUMMARY BACKGROUND DATA

Health utilities represent the strength of one's preferences under conditions of uncertainty. There are insufficient data to indicate how an individual would value levels of disability after a TBI.

METHODS

This was a cross-sectional web-based online convenience sampling adaptive survey. Using a standard gamble approach, participants evaluated their preferences for GOSE health states 1 year after a hypothetical TBI. The categorical GOSE was studied from vegetative state (GOSE2) to upper good recovery (GOSE8). Median (25th percentile, 75th percentile) health utility values for different GOSE states after TBI, ranging from -1 (worse than death) to 1 (full health), with 0 as reference (death).

RESULTS

Of 3508 eligible participants, 3235 (92.22%) completed the survey. Participants rated lower GOSE states as having lower utility, with some states rated as worse than death, though the relationship was nonlinear and intervals were unequal between health states. Over 75% of participants rated a vegetative state (GOSE2, absence of awareness and bedridden) and about 50% rated lower severe disability (GOSE3, housebound needing all-day assistance) as conditions worse than death.

CONCLUSIONS

In the largest investigation of public perceptions about post-TBI disability, we demonstrate unequally rated health states, with some states perceived as worse than death. Although limited by selection bias, these results may guide future comparative-effectiveness research and shared medical decision-making after neurologic injury.

Lifetime History of Traumatic Brain Injury With Loss of Consciousness and the Likelihood for Lifetime Depression and Risk Behaviors: 2017 BRFSS North Carolina

OBJECTIVE

Because of the growing concern about the potential effects of traumatic brain injuries (TBIs) on a child's developing brain and the potential impact of lifetime depression and risk behaviors associated with TBI, further exploration is warranted.

SETTING AND PARTICIPANTS

Data (N = 4917) from the 2017 North Carolina Behavioral Risk Factors Surveillance System (BRFSS).

DESIGN

Cross-sectional.

MAIN MEASURES

Examine whether a lifetime history of TBI with loss of consciousness (LOC) or having a history of TBI with LOC prior to 18 years of age was associated with a greater likelihood of lifetime depression, current binge drinking, and current cigarette and e-cigarette smoking.

RESULTS

Respondents with a history of TBI with LOC had 2.1 (95% CI, 1.6-2.8) times higher odds of lifetime depression and 1.7 to 1.8 (95% CI, 1.02-2.97) times higher odds of all risk behaviors than those without a lifetime history of TBI with LOC. There were no statistical differences between age of first TBI with LOC and lifetime depression, binge drinking, cigarette smoking, and e-cigarette use after controlling for key demographics.

CONCLUSION

These findings underscore the importance of increasing awareness among healthcare providers of the prevalence of lifetime depression and risk behaviors among individuals with a history of TBI and the need for improved screening and referrals to evidence-based services.

Prevention of Traumatic Brain Injury in the United States: Significance, New Findings, and Practical Applications

Traumatic brain injury (TBI) prevention programs aim to reduce trauma-related head injuries across the United States. In addition to epidemiological challenges, patients with TBI have a greater burden of disease and worse health outcomes than the general population. In these circumstances, the prevention of TBI is an important element in reducing the occurrence of post-traumatic health consequences in all settings and beyond. We completed a high-quality overview of TBI prevention programs using the public health approach to identify the most compelling risks to individuals through surveillance, data analysis, and field assessment. We explored the evidence-based programs that are proven to help individuals reduce the risk of TBI. To date, TBI programs have been very efficient, as evidenced by a sustained downturn in TBI incidence. However, recent socioeconomic and epidemiological challenges in the United States are affecting state and local TBI prevention efforts. This article is focused on strategies and solutions to reduce risks and/or consequences associated with head injuries from motor vehicle accidents in New York City. We believe this report is essential to guide the design and implementation of adequate preventive strategies and providing safe and high-quality patient care across all settings where healthcare is delivered.

Optimal Partial Pressure of Oxygen Affects Outcomes in Patients With Severe Traumatic Brain Injury

Introduction Severe traumatic brain injury (TBI) is a leading cause of death and disability. Not all neuronal damage occurs at the time of primary injury, but rather TBI initiates a cascade of events that leads to secondary brain injury. Oxygenation is one crucial factor in maintaining brain tissue homeostasis post-injury. We performed a retrospective review of patients admitted to a single trauma center after TBI. Statistical analysis was performed to ascertain if the measured partial pressure of oxygen (PaO₂) affected overall outcome at the time of discharge from the hospital. Materials and Methods Statistical analysis was performed retrospectively on patients admitted with a Glasgow Coma Scale (GCS) < 8 and a diagnosis of TBI. GCS and Glasgow Outcome Scale (GOS) were calculated from physical examination findings at the time of hospital discharge or death. Patient data were separated into two groups: those with consistently higher average PaO₂ scores (≥ 150 mmHg; n = 7) and those with lower average PaO₂ scores (< 150 mmHg; n = 8). The minimum requirement to be categorized in the consistently higher group was to have an average hospital day 1 through 5 PaO₂ value of ≥ 150 mmHg. Results Patients with consistent hospital Day 1 through 5 PaO₂ scores of ≥ 150 mmHg had statistically significant higher GCS scores at the end of intensive care unit (ICU)-level care or hospital discharge (mean = 12, p = 0.01), compared to those in group 2 with lower PaO₂ levels (mean = 7.9). There was no statistically significant difference in GOS when comparing the two groups (p = 0.055); however, the data did show a trend toward significance. Discussion and Conclusion In our study we analyzed patients diagnosed with TBI and stratified them into groups based on PaO₂ ≥ or < 150 mmHg. We demonstrate overall outcome improvement based on GCS with a trend toward improved GOS. The GCS showed statistical significance in patients with PaO₂ consistently ≥ 150 mmHg versus those in group 2 over the first five days of hospitalization.

Administration of Levetiracetam in Traumatic Brain Injury: Is it Warranted?

Background Antiepileptic agents are recommended to prevent early post-traumatic seizures (PTS) within seven days of injury in patients with severe traumatic brain injury (TBI). These agents are not routinely recommended for patients with mild-to-moderate TBI, defined as Glasgow Coma Scale (GCS) score > 8. At St. Joseph Mercy Oakland, levetiracetam (LEV) is commonly prescribed to prevent PTS. The objective of this study was to evaluate the appropriateness of LEV use in patients with mild, moderate, and severe TBI. Methods This retrospective cohort study evaluated the use of LEV in adult patients admitted with TBI over a five-year period. Patients who were younger than 18 years, had a history of seizures, were transferred to a tertiary center, or succumbed to their injuries were excluded. The primary outcome was appropriateness of LEV use. Secondary outcomes included duration of LEV treatment and rate of seizures. Results Of the 448 patients evaluated, 36 patients were excluded. Of the 412 included patients, 403 (97.8%) had a non-severe TBI, defined as GCS score > 8. In patients with non-severe TBI, 153 (38%) received LEV and 94 (23.3%) received LEV for more than seven days. Additionally, 105 (26.1%) patients with non-severe TBI were discharged with a prescription for LEV despite not having a seizure during hospitalization. All six patients with non-severe TBI who experienced a seizure were receiving LEV. Conclusions Inappropriate use of LEV is common in patients admitted with non-severe TBI, with many patients continuing LEV post-discharge. With careful patient selection, patients with mild and moderate TBI likely do not need seizure prophylaxis with LEV. Education on appropriate indication and duration of LEV in patients with TBI is warranted.

Increased Brain Tissue Oxygen Monitoring Threshold to Improve Hospital Course in Traumatic Brain Injury Patients

Introduction

This article is a retrospective analysis of the neurosurgical census at our institution to determine an optimal threshold for brain tissue oxygenation (PbtO2). The use of brain tissue oxygen monitoring has been in place for approximately three decades but data suggesting optimal thresholds to improve outcomes have been lacking. Though there are multiple modalities to monitor cerebral oxygenation, the monitoring of brain tissue oxygen tension has been deemed the gold standard. Still, it is not clear exactly how reductions in PbtO2 should be treated or what appropriate thresholds to treat might be. The aim of our study was to determine if our threshold of 28 mmHg for a good functional outcome could be correlated to the Glasgow Coma Scale (GCS) and Glasgow Outcome Scale (GOS).

Methods

A retrospective analysis of the Arrowhead Regional Medical Center (ARMC) Neurosurgery Census was performed. Patients from 2017-2019 who had placement of Licox® cerebral oxygen monitoring sensors (Integra® Lifesciences, Plainsboro Township, New Jersey) were included in the analysis. Fifteen patients were consecutively identified, all of which presented with traumatic brain injury (TBI). Data on age, gender, days in the intensive care unit (ICU), days before discharge or end of medical care, admission GCS, hospital length of stay, GOS, maximum and minimum PbtO2 values for five days following insertion, minimum and maximum intracranial pressures (ICPs), and brain temperature were included for analysis. Patient data were separated into two groups; those with consistently higher PbtO2 scores (≥ 28 mmHg; n = 7) and those with inconsistent/lower PbtO2 scores (< 28 mmHg; n = 8). Standard student t-tests were used to find potential statistical differences between the groups (α = 0.05).

Results

There were seven patients in the consistently high PbtO2 category (≥ 28 mmHg) and eight patients in the inconsistent/low PbtO2 category (<28 mmHg). The average maximum and minimum PbtO2 for the group displaying worse outcomes (as defined by GCS/GOS) was 23.0 mmHg and 14 mmHg, respectively. Those with consistent Day 2 PbtO2 scores of ≥ 28 mmHg had significantly higher GCS scores at discharge/end of medical care (p < 0.05). Average GCS for the patient group with >28 mmHg PbtO2 averaged over Days 2-5 group was 11.4 (n=7). Average GCS for the <28 group was 7.0 (n=8). The GCS for the >28 group was 63% higher than found in the <28 group (p = 0.03). GOS scores were significantly higher in those with consistently higher PbtO2 (≥ 28) than those with lower PbtO2 scores (< 28). The averages were 3.5 in the higher PbtO2 group as compared to 2 in the lower PbtO2 group.

Conclusion

Along with ICP monitors and monitoring in the assessment of CPP, brain tissue oxygenation allows yet another metric by which to optimize treatment in TBI patients. At our institution, a PbtO2 level of ≥ 28 mmHg is targeted in order to facilitate a good functional outcome in TBI patients. Keeping patients at this level improves GCS and GOS at discharge/end of medical treatment.

Correspondence of the Boston Assessment of Traumatic Brain Injury-Lifetime and the VA Comprehensive TBI Evaluation

OBJECTIVE

To compare the diagnosis of positive versus negative for mild traumatic brain injury (mTBI) using the Boston Assessment of TBI-Lifetime (BAT-L), a validated forensic clinical interview used to identify TBI in research, to the diagnosis of mTBI in the clinical polytrauma service using the Comprehensive TBI Evaluation (CTBIE).

PARTICIPANTS

Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn Veterans who were enrolled in the Translational Research Center for TBI and Stress Disorders longitudinal cohort study and received a CTBIE at a Veterans Health Administration healthcare facility (n = 104).

MAIN MEASURES

The BAT-L, CTBIE, and Neurobehavioral Symptom Inventory.

RESULTS

There was poor correspondence between the BAT-L and CTBIE mTBI diagnoses (κ = 0.283). The CTBIE showed moderate sensitivity but poor specificity relative to the BAT-L. The agreement did not improve after removing individuals who had failed symptom validity measures, as assessed by the Validity-10 scale of the Neurobehavioral Symptom Inventory.

CONCLUSIONS

This lack of correspondence highlights the difficulties in diagnosing mTBI in Veterans using retrospective self-report. Future work is needed to establish a reliable and valid method for identifying military mTBI both for the care of our Veterans and for appropriate distribution of benefits.

Optic Nerve Sheath Diameter Correlation with Elevated Intracranial Pressure Determined via Ultrasound

Background

The early detection of elevated intracranial pressure (ICP) can not only prevent mortality but also aid in more aggressive management. Brain computed tomography (CT) is a mainstay modality in detecting elevated ICP, but the feasibility of using brain CTs to detect elevated ICP in critically ill patients is limited, especially for patients who require high levels of inotropic support. The optic nerve sheath is a direct extension of the brain meninges. Therefore, the elevation of ICP is directly transmitted to the sheath. Measuring the optic nerve sheath diameter (ONSD) through ultrasound (US) is a bedside, noninvasive means to detect elevated ICP. The goal of this study was to assess the correlation of ONSD with elevated ICP as measured via US in an intensive care unit (ICU).

Methods

We conducted a six-month prospective, single-center, observational study of mass effect stroke patients aged 18 to 65 years who had a traumatic brain injury (TBI) and were admitted to the ICU. Patients with chronic hydrocephalus, extensive local orbit trauma, a pre-existing ocular disease affecting the optic nerve and/or orbital cavity, hyperthyroidism with exophthalmos, and facial trauma affecting the orbits and/or eyeballs were excluded. We measured the ONSD at the entry of optic nerve into the globe using two-dimensional (2D) US.

Results

One hundred patients were included in the study. Forty-nine patients had diffuse cerebral edema detected on CT scan correlating with increased ONSD notable via bedside US. The mean ONSD related to CT-detectable elevated ICP was 0.61 cm. The sensitivity for the ONSD cut-off value of ≥5.8 mm was 94% (95% confidence interval [CI], 84.05% to 98.79%), and the specificity was 96.08% (95% CI, 86.7% to 99.52%).The positive predictive value was 92.08% (95% CI, 86.28% to 98.96%), and the negative predictive value was 94.23% (95% CI, 84.47% to 98.00%).

Conclusion

The greatest accuracy in ONSD was found with a cut-off of >0.58 cm in patients with positive CT brain findings. Therefore, US can be used as an initial screening test when physicians suspect a patient has elevated ICP.

Rodent Behavioral Testing to Assess Functional Deficits Caused by Microelectrode Implantation in the Rat Motor Cortex

Medical devices implanted in the brain hold tremendous potential. As part of a Brain Machine Interface (BMI) system, intracortical microelectrodes demonstrate the ability to record action potentials from individual or small groups of neurons. Such recorded signals have successfully been used to allow patients to interface with or control computers, robotic limbs, and their own limbs. However, previous animal studies have shown that a microelectrode implantation in the brain not only damages the surrounding tissue but can also result in functional deficits. Here, we discuss a series of behavioral tests to quantify potential motor impairments following the implantation of intracortical microelectrodes into the motor cortex of a rat. The methods for open field grid, ladder crossing, and grip strength testing provide valuable information regarding the potential complications resulting from a microelectrode implantation. The results of the behavioral testing are correlated with endpoint histology, providing additional information on the pathological outcomes and impacts of this procedure on the adjacent tissue.

Nicotine-Induced Conditional Place Preference Is Affected by Head Injury: Correlation with Dopamine Release in the Nucleus Accumbens Shell

BACKGROUND

Traumatic brain injury is known to impact dopamine-mediated reward pathways, but the underlying mechanisms have not been fully established.

METHODS

Nicotine-induced conditional place preference was used to study rats exposed to a 6-psi fluid percussion injury with and without prior exposure to nicotine. Preference was quantified as a score defined as (C1 - C2) / (C1 + C2), where C1 is time in the nicotine-paired compartment and C2 is time in the saline-paired compartment. Subsequent fast-scan cyclic voltammetry was used to analyze the impact of nicotine infusion on dopamine release in the shell portion of the nucleus accumbens. To further determine the influence of brain injury on nicotine withdrawal, nicotine infusion was administered to the rats after fluid percussion injury. The effects of fluid percussion injury on conditional place preference after prior exposure to nicotine and abstinence or withdrawal from nicotine were also assessed.

RESULTS

After traumatic brain injury, dopamine release was reduced in the nucleus accumbens shell, and nicotine-induced conditional place preference preference was significantly impaired. Preference scores of control, sham-injured, and fluid percussion injury groups were 0.1627±0.04204, 0.1515±0.03806, and -0.001300±0.04286, respectively. Nicotine-induced conditional place preference was also seen in animals after nicotine pretreatment, with a conditional place preference score of 0.07805±0.02838. Nicotine preexposure substantially increased tonic dopamine release in sham-injured animals, but it did not change phasic release; nicotine exposure after fluid percussion injury enhanced phasic release, though not to the same levels seen in sham-injured rats. Conditioned preference was related not only to phasic dopamine release (r=0.8110) but also to the difference between tonic and phasic dopamine levels (r=0.9521).

CONCLUSIONS

Traumatic brain injury suppresses dopamine release from the shell portion of the nucleus accumbens, which in turn significantly alters reward-seeking behavior. These results have important implications for tobacco and drug use after traumatic brain injury.

Does intracranial pressure management hurt more than it helps in traumatic brain injury?

Traumatic brain injury (TBI) is the leading cause of death after traumatic injury. Raised intracranial pressure (ICP) is particularly associated with poor TBI outcomes, prompting clinicians to monitor this parameter, using it to guide therapies aimed at reducing pressures. Despite this approach being recommended by several bodies such as the Brain Trauma Foundation and the American College of Surgeons, the evidence demonstrating that ICP-guided therapy improves outcome is limited. The topic was debated at the 36th Annual Point/Counterpoint Acute Care Surgery Conference and the following article summarizes the discussants points of view along with a summary of the evidence.

The influence of traumatic brain injury on treatment outcomes of Concurrent Treatment for PTSD and Substance Use Disorders Using Prolonged Exposure (COPE) in veterans

BACKGROUND

The co-occurrence of posttraumatic stress disorder (PTSD), substance use disorders (SUD), and traumatic brain injury (TBI) in veterans of Operations Enduring/Iraqi Freedom and New Dawn has received much attention in the literature. Although hypotheses have been presented and disseminated that TBI history will negatively influence treatment response, little data exist to support these claims. The present study investigates the influence of TBI history on response to COPE (Concurrent Treatment of PTSD and SUD Using Prolonged Exposure), a 12-session, integrated psychotherapy designed to address co-occurring PTSD and SUD.

METHOD

Participants were 51 veterans with current PTSD and SUD enrolled in a clinical trial examining COPE. Assessments of PTSD symptoms, substance use, and depression were collected at baseline and each treatment session. A TBI measure was used to dichotomize veterans into groups with and without a history of TBI (ns=30 and 21, respectively).

RESULTS

Participants with and without TBI history demonstrated significant improvements in PTSD and depression symptoms during the course of treatment. However, participants with TBI history experienced less improvement relative to participants without TBI history.

CONCLUSIONS

The present findings suggest that, although patients with a TBI history respond to treatment, their response to treatment was less so than that observed in patients without a TBI history. As such, identification, symptom monitoring, and treatment practices may require alteration and further special consideration in individuals with PTSD, SUD and TBI.

Current practice in total-body irradiation: results of a Canada-wide survey

BACKGROUND

Total-body irradiation (tbi) is used to condition patients before bone marrow transplant. A variety of tbi treatment strategies have been described and implemented, but no consensus on best practice has been reached. We report on the results of a survey created to assess the current state of tbi delivery in Canada.

RESULTS

A 19-question survey was distributed to 49 radiation oncology programs in Canada. Responses were received from 20 centres, including 12 centres that perform tbi. A variety of tbi dose prescriptions was reported, although 12 Gy in 6 fractions was used in 11 of the 12 centres performing tbi. Half of the centres also reported using a dose prescription unique to their facility. Most centres use an extended-distance parallel-opposed-pair technique, with the patient standing or lying on a stretcher against a wall. Others translate the patient under the beam, sweep the beam over the patient, or use a more complicated multi-field technique. All but 1 centre indicated that they attenuate the lung dose; only 3 centres indicated attenuating the dose for other organs at risk. The survey also highlighted the considerable resources used for tbi, including extra staff, prolonged planning and treatment times, and use of locally developed hardware or software.

CONCLUSIONS

At transplant centres, tbi is commonly used, but there is no commonly accepted approach to planning and treatment delivery. The important discrepancies in practice between centres in Canada creates an opportunity to prompt more discussion and collaboration between centres, improving consistency and uniformity of practice.

Impaired fracture healing with high non-union rates remains irreversible after traumatic brain injury in leptin-deficient mice

Patients with traumatic brain injury (TBI) and long-bone fractures can show increased callus formation. This effect has already been reproduced in wild-type (wt) mice. However, the mechanisms remain poorly understood. Leptin is significantly increased following TBI, while its role in bone healing remains unclear. The aim of this study was to evaluate fracture healing in leptin-deficient ob/ob mice and to measure any possible impact of TBI on callus formation. 138 female, 12 weeks old, ob/ob mice were divided into four groups: Control, fracture, TBI and combined trauma. Osteotomies were stabilized with an external fixator; TBI was induced with Controlled Cortical Impact Injury. Callus bridging was weekly evaluated with in vivo micro-CT. Biomechanical testing was performed ex vivo. Micro-CT showed high non-union rates after three and four weeks in the fracture and combined trauma group. No differences were observed in callus volume, density and biomechanical properties at any time point. This study shows that bony bridging is impaired in the present leptin-deficient trauma model. Furthermore, the phenomenon of increased callus formation after TBI could not be reproduced in ob/ob mice, as in wt mice. Our findings suggest that the increased callus formation after TBI may be dependent on leptin signaling.

Probabilistic Matching Approach to Link Deidentified Data from a Trauma Registry and a Traumatic Brain Injury Model System Center

OBJECTIVE

There is no civilian traumatic brain injury database that captures patients in all settings of the care continuum. The linkage of such databases would yield valuable insight into possible care interventions. Thus, the objective of this article is to describe the creation of an algorithm used to link the Traumatic Brain Injury Model System (TBIMS) to trauma data in state and national trauma databases.

DESIGN

The TBIMS data from a single center was randomly divided into two sets. One subset was used to generate a probabilistic linking algorithm to link the TBIMS data to the center's trauma registry. The other subset was used to validate the algorithm. Medical record numbers were obtained and used as unique identifiers to measure the quality of the linkage. Novel methods were used to maximize the positive predictive value.

RESULTS

The algorithm generation subset had 121 patients. It had a sensitivity of 88% and a positive predictive value of 99%. The validation subset consisted of 120 patients and had a sensitivity of 83% and a positive predictive value of 99%.

CONCLUSIONS

The probabilistic linkage algorithm can accurately link TBIMS data across systems of trauma care. Future studies can use this database to answer meaningful research questions regarding the long-term impact of the acute trauma complex on health care utilization and recovery across the care continuum in traumatic brain injury populations.

Adherence to Brain Trauma Foundation guidelines for management of traumatic brain injury patients: study protocol for a systematic review and meta-analysis

BACKGROUND

Traumatic brain injury (TBI) is a leading cause of death and disability around the world. Management based on Brain Trauma Foundation (BTF) guidelines is widely accepted and thought to improve outcome. The objectives of this systematic review are to give an overview of adherence to the BTF guidelines, describe factors influencing adherence, and study the effect of guideline-based management on outcome.

METHODS/DESIGN

We will search electronic bibliographic databases: PROSPERO, Medline, EMBASE, SCOPUS, NHS, CINAHL, Cochrane Database, and ProQuest Dissertations and Theses Global. Two investigators will independently screen all titles, abstracts, and articles and select Randomized Controlled Trial (RCT), cohort studies, case-control studies, and case series reporting the adherence rate, factors influencing adherence, and mortality or morbidity. These investigators will also independently extract data using a pre-designed and pilot-tested standardized electronic data extraction form and assess the risk of bias. We will exclude pediatric and military-related TBI studies, studies that included fewer than ten patients or addressed adherence to pre-hospital guidelines. Narrative synthesis and if appropriate, quantitative meta-analysis clustered by type of recommendation will be reported.

DISCUSSION

This study is expected to demonstrate the current level of professionals' adherence to BTF guidelines in patients with severe traumatic brain injury, it will describe the factors influencing adherence, which may provide valuable input for development of strategies to successfully increase adherence. In addition, if the studies are sufficiently homogenous, it will describe the effect of these guidelines on patient outcome.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015017794.