The epidemiology of traumatic brain injuries treated in emergency departments in North Carolina, 2010-2011

Impact of Fall Risk and Direct Oral Anticoagulant Treatment on Quality-Adjusted Life-Years in Older Adults with Atrial Fibrillation: A Markov Decision Analysis

BACKGROUND AND OBJECTIVE

The decision to initiate anticoagulation in older adults with atrial fibrillation is complicated by the benefit of ischemic stroke prevention vs the risk of falls resulting in major bleeds. The objective of this study was to assess the impact of different treatments including direct oral anticoagulants on quality-adjusted life-years (QALYs) in patients aged 75 years and older with atrial fibrillation in the context of falls.

METHODS

A Markov decision process was constructed for older patients with atrial fibrillation taking no anti-thrombotic, aspirin, warfarin, rivaroxaban, and apixaban. Input probabilities for clinical events were estimated from the available literature. One-way and two-way sensitivity analyses were performed by measuring the impact of varying input probabilities of clinical events on QALY outcomes.

RESULTS

The base-case scenario estimated that older adults treated with no anti-thrombotic, aspirin, warfarin, rivaroxaban, and apixaban had QALYs of 8.03, 8.69, 10.38, 11.02, and 11.56, respectively. The sensitivity analysis estimated that an older adult would need to fall over 45 (rivaroxaban) and 458 (apixaban) times per year for the QALY of a direct oral anticoagulant to be lower than that of aspirin.

CONCLUSIONS

Older adults with atrial fibrillation benefit from stroke protection of anticoagulants, especially direct oral anticoagulants, even if they are at high risk of falls. Clinicians should not consider fall risk as a deciding factor for withholding anticoagulation in this population of patients.

Which older emergency patients are at risk of intracranial bleeding after a fall? A protocol to derive a clinical decision rule for the emergency department

INTRODUCTION

Falling on level ground is now the most common cause of traumatic intracranial bleeding worldwide. Older adults frequently present to the emergency department (ED) after falling. It can be challenging for clinicians to determine who requires brain imaging to rule out traumatic intracranial bleeding, and often head injury decision rules do not apply to older adults who fall. The goal of our study is to derive a clinical decision rule, which will identify older adults who present to the ED after a fall who do not have clinically important intracranial bleeding.

METHODS AND ANALYSIS

This is a prospective cohort study enrolling patients aged 65 years or older, who present to the ED of 11 hospitals in Canada and the USA within 48 hours of having a fall. Patients are included if they fall on level ground, off a chair, toilet seat or out of bed. The primary outcome is the diagnosis of clinically important intracranial bleeding within 42 days of the index ED visit. An independent adjudication committee will determine the primary outcome, blinded to all other data. We are collecting data on 17 potential predictor variables. The treating physician completes a study data form at the time of initial assessment, prior to brain imaging. Data extraction is supplemented by an independent, structured electronic medical record review. We will perform binary recursive partitioning using Classification and Regression Trees to derive a clinical decision rule.

ETHICS AND DISSEMINATION

The study was initially approved by the Hamilton Integrated Research Ethics Committee and subsequently approved by the research ethics boards governing all participating sites. We will disseminate our results by journal publication, presentation at international meetings and social media.

TRIAL REGISTRATION NUMBER

NCT03745755.

Clinical Predictors of Intracranial Bleeding in Older Adults Who Have Fallen: A Cohort Study

OBJECTIVES

Emergency department (ED) visits among older adults are frequently instigated by a fall at home. Some of these patients develop intracranial bleeding. The aim of this study was to identify the incidence of intracranial bleeding and the associated clinical features in older adults who present to the ED after falling.

DESIGN

Prospective cohort study.

SETTING

Three Canadian EDs.

PARTICIPANTS

A total of 2 176 patients age 65 years or older who presented to the ED with a fall were assessed, and 1753 were included. Inclusion criteria were a fall on level ground, off a bed, chair, or toilet, or from one or two steps within 48 hours.

MEASUREMENTS

Emergency physicians recorded predefined clinical findings on initial assessment. The primary outcome was intracranial bleeding, diagnosed either by computed tomography at the index visit or within 42 days. Associations between baseline clinical findings and the presence of intracranial bleeding were assessed with multivariable logistic regression.

RESULTS

A total of 1753 patients (median age = 82 y) were enrolled, of whom 39% were male, 35% were on antiplatelet therapy, and 25% were on an anticoagulant. The incidence of intracranial bleeding was 5.0% (95% confidence interval [CI] = 4.1-6.1). Overall, 76 patients were diagnosed at the index ED visit, and 12 were diagnosed during follow-up. Multivariable regression identified four clinical variables that were independently associated with intracranial bleeding: new abnormalities on neurologic examination (odds ratio [OR] = 4.4; 95% CI = 2.4-8.1), bruise or laceration on the head (OR = 4.3; 95% CI = 2.7-7.0), chronic kidney disease (OR = 2.4; 95% CI = 1.3-4.6), and reduced Glasgow Coma Scale from normal (OR = 1.9; 95% CI = 1.0-3.4).

CONCLUSION

The incidence of intracranial bleeding in our study was 5.0%. We found significant associations between intracranial bleeding and four simple clinical variables. We did not find significant associations between intracranial bleeding and antiplatelet or anticoagulant use. J Am Geriatr Soc 68:970-976, 2020.

Ten-year trends in traumatic brain injury: a retrospective cohort study of California emergency department and hospital revisits and readmissions

OBJECTIVE

To describe visits and visit rates of adults presenting to emergency departments (EDs) with a diagnosis of traumatic brain injury (TBI). TBI is a major cause of death and disability in the USA; yet, current literature is limited because few studies examine longer-term ED revisits and hospital readmission patterns of TBI patients across a broad spectrum of injury severity, which can help inform potential unmet healthcare needs.

DESIGN

We performed a retrospective cohort study.

SETTING

We analysed non-public patient-level data from California's Office of Statewide Health Planning and Development for years 2005 to 2014.

PARTICIPANTS

We identified 1.2 million adult patients aged ≥18 years presenting to California EDs and hospitals with an index diagnosis of TBI.

PRIMARY AND SECONDARY OUTCOME MEASURES

Our main outcomes included revisits, readmissions and mortality over time. We also examined demographics, mechanism and severity of injury and disposition at discharge.

RESULTS

We found a 57.7% increase in the number of TBI ED visits, representing a 40.5% increase in TBI visit rates over the 10-year period (346-487 per 100 000 residents). During this time, there was also a 33.8% decrease in the proportion of patients admitted to the hospital. Older, publicly insured and black populations had the highest visit rates, and falls were the most common mechanism of injury (45.5% of visits). Of all patients with an index TBI visit, 40.5% of them had a revisit during the first year, with 46.7% of them seeking care at a different hospital from their initial hospital or ED visit. Additionally, of revisits within the first year, 13.4% of them resulted in hospital readmission.

CONCLUSIONS

The large proportion of patients with TBI who are discharged directly from the ED, along with the high rates of revisits and readmissions, suggest a role for an established system for follow-up, treatment and care of TBI.

The epidemiology of mild traumatic brain injury: the Trondheim MTBI follow-up study

Background

Mild traumatic brain injury (MTBI) is a frequent medical condition, and some patients report long-lasting problems after MTBI. In order to prevent MTBI, knowledge of the epidemiology is important and potential bias in studies should be explored.

Aims of this study were to describe the epidemiological characteristics of MTBI in a Norwegian area and to evaluate the representativeness of patients successfully enrolled in the Trondheim MTBI follow-up study.

Methods

During 81 weeks in 2014 and 2015, all persons aged 16–60 years, presenting with possible MTBI to the emergency department (ED) at St. Olavs Hospital, Trondheim University Hospital or to Trondheim municipal outpatient ED, were evaluated for participation in the follow-up study. Patients were identified by CT referrals and patient lists. Patients who were excluded or missed for enrolment in the follow-up study were recorded.

Results

We identified 732 patients with MTBI. Median age was 28 years, and fall was the most common cause of injury. Fifty-three percent of injuries occurred during the weekend. Only 29% of MTBI patients were hospitalised. Study specific exclusion criteria were present in 23%. We enrolled 379 in the Trondheim MTBI follow-up study. In this cohort, Glasgow Coma Scale score was 15 at presentation in 73%; 45% of patients were injured under the influence of alcohol. Patients missed for inclusion were significantly more often outpatients, females, injured during the weekend, and suffering violent injuries, but differences between enrolled and not enrolled patients were small.

Conclusion

Two thirds of all patients with MTBI in the 16–60 age group were treated without hospital admission, patients were often young, and half of the patients presented during the weekend. Fall was the most common cause of injury, and patients were commonly injured under the influence of alcohol, which needs to be addressed when considering strategies for prevention. The Trondheim MTBI follow-up study comprised patients who were highly representative for the underlying epidemiology of MTBI.

Estimating the international burden of sport-related death: a review of data sources

INTRODUCTION

Despite detailed recommendations for sports injury data capture provided since the mid-1990s, international data collection efforts for sport-related death remains limited in scope. The purpose of this paper was to review the data sources available for studying sport-related death and describe their key features, coverage, accessibility and strengths and limitations.

METHODS

The outcomes of interest for this review was death occurring as a result of participation in organised sport-related activity. Data sources used to enumerate death in sport were identified, drawing from the authors' knowledge/experience and review of key references from international organisations. The general purpose, case identification, structure, strengths and limitations of each source in relation to collection of data for sport-related death were summarised, drawing on examples from the international published literature to illustrate this application.

RESULTS

Seven types of resources were identified for capturing deaths in sport. Data sources varied considerably in their ability to identify: participant status, sport relatedness of the death, types of sport-related deaths they capture, level of detail provided about the circumstances and medical care received. The most detailed sources were those that were dedicated to sports surveillance. Sport relatedness and type of sport may not be reliably captured by systems not dedicated to sports injury surveillance. Only one source permitted international comparisons and was limited to one sport (soccer).

CONCLUSION

Data on sport-related death are currently collected across a wide variety of data sources. This review highlights the need for robust, comprehensive approaches with standardised methodologies enabling linkage between sources and international comparisons.

Target-controlled Infusion Propofol Versus Sevoflurane Anaesthesia for Emergency Traumatic Brain Surgery: Comparison of the Outcomes

Background

The choice of anaesthetic techniques is important for the outcome of traumatic brain injury (TBI) emergency surgery. The objective of this study was to compare patient outcomes for target-controlled infusion (TCI) of propofol and sevoflurane anaesthesia.

Methods

A total of 110 severe TBI patients, aged 18-60, who underwent emergency brain surgery were randomised into Group T (TCI) (n = 55) and Group S (sevoflurane) (n = 55). Anaesthesia was maintained in Group T with propofol target plasma concentration of 3-6 μg/mL and in Group S with minimum alveolar concentration (MAC) of sevoflurane 1.0-1.5. Both groups received TCI remifentanil 2-8 ng/mL for analgesia. After the surgery, patients were managed in the intensive care unit and were followed up until discharge for the outcome parameters.

Results

Demographic characteristics were comparable in both groups. Differences in Glasgow Outcome Scale (GOS) score at discharge were not significant between Group T and Group S (P = 0.25): the percentages of mortality (GOS 1) [27.3% versus 16.4%], vegetative and severe disability (GOS 2-3) [29.1% versus 41.8%] and good outcome (GOS 4-5) [43.6% versus 41.8%] were comparable in both groups. There were no significant differences in other outcome parameters.

Conclusion

TCI propofol and sevoflurane anaesthesia were comparable in the outcomes of TBI patients after emergency surgery.

Validation of Acoustic Wave Induced Traumatic Brain Injury in Rats

BACKGROUND

This study looked to validate the acoustic wave technology of the Storz-D-Actor that inflicted a consistent closed-head, traumatic brain injury (TBI) in rats. We studied a range of single pulse pressures administered to the rats and observed the resulting decline in motor skills and memory. Histology was observed to measure and confirm the injury insult.

METHODS

Four different acoustic wave pressures were studied using a single pulse: 0, 3.4, 4.2 and 5.0 bar (n = 10 rats per treatment group). The pulse was administered to the left frontal cortex. Rotarod tests were used to monitor the rats' motor skills while the water maze test was used to monitor memory deficits. The rats were then sacrificed ten days post-treatment for histological analysis of TBI infarct size.

RESULTS

The behavioral tests showed that acoustic wave technology administered an effective insult causing significant decreases in motor abilities and memory. Histology showed dose-dependent damage to the cortex infarct areas only.

CONCLUSIONS

This study illustrates that the Storz D-Actor effectively induces a repeatable TBI infarct, avoiding the invasive procedure of a craniotomy often used in TBI research.

The use of oculomotor, vestibular, and reaction time tests to assess mild traumatic brain injury (mTBI) over time

Objectives

The objective of this work is to examine the outcomes of a set of objective measures for evaluating individuals with minor traumatic brain injury (mTBI) over the sub‐acute time period. These methods involve tests of oculomotor, vestibular, and reaction time functions. This work expands upon published work examining these test results at the time of presentation.

Study Design

This study is a prospective age‐ and sex‐matched controlled study.

Materials and Methods

The subject group was composed of 106 individuals with mTBI and 300 age‐ and sex‐matched controls without a history of mTBI. All individuals agreeing to participate in the study underwent a battery of oculomotor, vestibular, and reaction time tests (OVRT). Those subjects with mTBI underwent these tests at presentation (within 6 days of injury) and 1 and 2weeks post injury. These outcomes were compared to each other over time as well as to results from the controls that underwent 1 test session.

Results

Six measures from 5 tests can classify the control and mTBI during Session 1 with a true positive rate (sensitivity) of 84.9% and true negative rate (specificity) of 97.0%. Patterns of abnormalities changed over time in the mTBI group and overall normalized in a subset of individuals at the third (final) testing session.

Conclusions

We describe an objective and effective second generation testing algorithm for diagnosing and following the prognosis of mTBI/concussion. This testing paradigm will allow investigators to institute better treatments and provide more accurate return to activity advice.

Level of Evidence

3

Acetazolamide Mitigates Astrocyte Cellular Edema Following Mild Traumatic Brain Injury

Non-penetrating or mild traumatic brain injury (mTBI) is commonly experienced in accidents, the battlefield and in full-contact sports. Astrocyte cellular edema is one of the major factors that leads to high morbidity post-mTBI. Various studies have reported an upregulation of aquaporin-4 (AQP4), a water channel protein, following brain injury. AZA is an antiepileptic drug that has been shown to inhibit AQP4 expression and in this study we investigate the drug as a therapeutic to mitigate the extent of mTBI induced cellular edema. We hypothesized that mTBI-mediated astrocyte dysfunction, initiated by increased intracellular volume, could be reduced when treated with AZA. We tested our hypothesis in a three-dimensional in vitro astrocyte model of mTBI. Samples were subject to no stretch (control) or one high-speed stretch (mTBI) injury. AQP4 expression was significantly increased 24 hours after mTBI. mTBI resulted in a significant increase in the cell swelling within 30 min of mTBI, which was significantly reduced in the presence of AZA. Cell death and expression of S100B was significantly reduced when AZA was added shortly before mTBI stretch. Overall, our data point to occurrence of astrocyte swelling immediately following mTBI, and AZA as a promising treatment to mitigate downstream cellular mortality.

Increased Network Excitability Due to Altered Synaptic Inputs to Neocortical Layer V Intact and Axotomized Pyramidal Neurons after Mild Traumatic Brain Injury

Mild traumatic brain injury (mTBI) can produce long lasting cognitive dysfunction. There is typically no cell death and only diffuse structural injury after mTBI. Thus, functional changes in intact neurons may contribute to symptoms. We have previously shown altered intrinsic properties of axotomized and intact neurons within 2 d after a central fluid percussion injury in mice expressing yellow fluorescent protein (YFP) that allow identification of axonal state prior to recording. Here, whole-cell patch clamp recordings were used to examine synaptic properties of YFP(+) layer V pyramidal neurons. An increased frequency of spontaneous and miniature excitatory postsynaptic currents (EPSCs) was recorded from axotomized neurons at 1 d and intact neurons at 2 d after injury, likely reflecting an increased number of afferents. This also was reflected in the increased amplitude of the EPSC evoked by local extracellular stimulation for all neurons from injured cortex and increased likelihood of producing an action potential for intact cells. Field potentials recorded in superficial layers after online deep layer stimulation contained a single negative peak in controls but multiple negative peaks in injured tissue. The amplitude of this evoked negativity was significantly larger than controls over a series of stimulus intensities at both the 1 d and 2 d survival times. Interictal-like spikes never occurred in the field potential recordings from controls but were observed in 20-80% of stimulus presentations in injured cortex. Together, these results suggest an overall increase in network excitability and the production of particularly powerful (intact) neurons that have both increased intrinsic and synaptic excitability.