Search

Despite considerable efforts to advance the science surrounding traumatic brain injury (TBI), formal efforts supporting the current and future implementation of scientific findings within clinical practice and healthcare policy are limited. While many and varied guidelines inform the clinical management of TBI across the spectrum, clinicians and healthcare systems are not broadly adopting, implementing, and/or adhering to them. As part of the Brain Trauma Blueprint TBI State of the Science, an expert workgroup was assembled to guide this review article, which describes: (1) possible etiologies of inadequate adoption and implementation; (2) enablers to successful implementation strategies; and (3) strategies to mitigate the barriers to adoption and implementation of future research.

The Brain Trauma Foundation (BTF) Guidelines for the Management of Severe Head Injury were the first clinical practice guidelines published by any surgical specialty. These guidelines have earned a reputation for rigor and have been widely adopted around the world. Implementation of these guidelines has been associated with a 50% reduction in mortality and reduced costs of patient care. Over their 25-yr history the traumatic brain injury (TBI) guidelines have been expanded, refined, and made increasingly more rigorous in conjunction with new clinical evidence and evolving methodologic standards. Here, we discuss the history and accomplishments of BTF guidelines for TBI as well as their limitations. We also discuss planned changes to future TBI guidelines intended to increase their utility and positive impact in an evolving medical landscape. Perhaps the greatest limitation of TBI guidelines now is the lack of high-quality clinical research as well as novel diagnostics and treatments with which to generate substantially new recommendations.

Introduction Cognitive processes such as perception and reasoning are preceded and dependent on attention. Because of the close overlap between neural circuits of attention and eye movement, attention may be objectively quantified with recording of eye movements during an attention-dependent task. Our previous work demonstrated that performance scores on a circular visual tracking task that requires dynamic synchronization of the gaze with the target motion can be impacted by concussion, sleep deprivation, and attention deficit/hyperactivity disorder. The current study examined the characteristics of performance on a standardized predictive visual tracking task in a large sample from a U.S. Military population to provide military normative data. Materials and Methods The sample consisted of 1,594 active duty military service members of either sex aged 18-29 years old who were stationed at Fort Hood Army Base. The protocol was reviewed and approved by the U.S. Army Medical Research and Materiel Command Institutional Review Board. Demographic, medical, and military history data were collected using questionnaires, and performance-based data were collected using a circular visual tracking test and Trail Making Test. Differences in visual tracking performance by demographic characteristics were examined with a multivariate analysis of variance, as well as a Kolmogorov-Smirnov test and a rank-sum test. Associations with other measures were examined with a rank-sum test or Spearman correlations. Results Robust sex differences in visual tracking performance were found across the various statistical models, as well as age differences in several isolated comparisons. Accordingly, norms of performance scores, described in terms of percentile standings, were developed adjusting for age and sex. The effects of other measures on visual tracking performance were small or statistically non-significant. An examination of the score distributions of various metrics suggested that strategies preferred by men and women may optimize different aspects of visual tracking performance. Conclusion This large-scale quantification of attention, using dynamic visuomotor synchronization performance, provides rigorously characterized age- and sex-based military population norms. This study establishes analytics for assessing normal and impaired attention and detecting changes within individuals over time. Practical applications for combat readiness and surveillance of attention impairment from sleep insufficiency, concussion, medication, or attention disorders will be enhanced with portable, easily accessible, fast, and reliable dynamic eye-tracking technologies.

When the fourth edition of the Brain Trauma Foundation's Guidelines for the Management of Severe Traumatic Brain Injury were finalized in late 2016, it was known that the results of the RESCUEicp (Trial of Decompressive Craniectomy for Traumatic Intracranial Hypertension) randomized controlled trial of decompressive craniectomy would be public after the guidelines were released. The guideline authors decided to proceed with publication but to update the decompressive craniectomy recommendations later in the spirit of “living guidelines,” whereby topics are updated more frequently, and between new editions, when important new evidence is published. The update to the decompressive craniectomy chapter presented here integrates the findings of the RESCUEicp study as well as the recently published 12-mo outcome data from the DECRA (Decompressive Craniectomy in Patients With Severe Traumatic Brain Injury) trial. Incorporation of these publications into the body of evidence led to the generation of 3 new level-IIA recommendations; a fourth previously presented level-IIA recommendation remains valid and has been restated. To increase the utility of the recommendations, we added a new section entitled Incorporating the Evidence into Practice. This summary of expert opinion provides important context and addresses key issues for practitioners, which are intended to help the clinician utilize the available evidence and these recommendations. The full guideline can be found at: https://braintrauma.org/guidelines/guidelines-for-the-management-of-severe-tbi-4th-ed#/.

Background: The targeting rule was adopted by the National Collegiate Athletic Association (NCAA) in 2008 to discourage dangerous contact during collegiate American football competition. Although targeting rules have been emphasized as a means to reduce concussion rates, there is currently no evidence that targeting plays are higher risk for concussion than other plays in American football. Purpose: To compare the rate of concussion occurring during targeting versus nontargeting plays in American collegiate football. Study Design: Cross-sectional study. Methods: Concussions occurring in games in the 2016-2019 Pac-12 Conference were classified as having occurred during either (1) a play where a targeting penalty was called or (2) all other plays. Targeting plays were further categorized to either those in which the call was upheld or those overturned by the on-field official after replay review. The number of targeting plays and the total number of plays during games were also recorded. Concussion incidence (per 1000 plays) and risk ratios were calculated. Results: Overall, 538 games with 68,670 plays were reviewed, during which 213 concussions occurred (15 during plays where targeting was called and 198 on other plays) and 141 targeting penalties were called. The incidence of concussion was 106.4/1000 plays for targeting plays (including 141.2/1000 upheld targeting fouls and 53.6/1000 overturned targeting fouls) and 2.9/1000 plays for nontargeting plays. The risk of concussion during targeting plays was 36.9 (95% CI, 22.4-60.7) times greater than that for all other plays. The risk of concussion during targeting plays upheld was 49.0 (95% CI, 28.5-84.2) times greater than that for all other plays. Conclusion: Concussion risk was significantly higher during plays in which targeting was called, especially those in which targeting fouls were upheld. Clinical Relevance: This study supports eliminating or reducing targeting from American football. The results of this study suggest that players should be screened for concussion after targeting plays are called.

OBJECTIVE Female athletes may be more likely to sustain a concussion and may vary in symptom presentation and neurocognitive impairments as compared with males. Scientific literature is limited by subjective assessments and underproportioned representation of women-the scope and etiology of sex-based differences are unknown. This study investigates sex-based differences in sports concussion assessments among college varsity athletes. DESIGN AND SETTING Retrospective study of an institution's athletic head injury database. PARTICIPANTS Acute postinjury and baseline data from 111 college athletes sustaining concussions between 2016 and 2018, diagnosed by a concussion specialist physician. MAIN OUTCOME MEASURES Concussion assessments examined included the Sports Concussion Assessment Tool (SCAT5) and Vestibular Oculomotor Screening (VOMS) performed within 3 days (24-72 hours) of injury. RESULTS No significant difference by sex was observed in the SCAT5 total symptom evaluation scores or severity scores, Standardized Assessment of Concussion, or Balance Error Scoring System (P > .05) within 3 days of head injury. Females did report more "pressure in the head" severity scores from baseline to postconcussion (2.7 ± 1.5 increased symptomatology in females vs 1.8 ± 1.3 increase in males, P = .007). The VOMS test resulted in significant sex differences in smooth pursuit [0.6 ± 1.4 increase in females (P < .001) vs 0.2 ± 0.6 increase in males (P = .364)], horizontal saccades [0.6 ± 1.2 increase in females (P < .001) vs 0.2 ± 0.5 increase in males (P = .149)], and vertical saccades [0.9 ± 1.9 increase in females (P < .001) vs 0.3 ± 0.7 increase in males (P = .206)]. CONCLUSION Our study did not show sex-based differences in baseline or acute postconcussive symptom reporting in most concussion assessment parameters, challenging previous research suggesting that females report more symptoms than males. Females did have significant differences in symptom provocation using the VOMS.

Background: The subdural evacuation port system (SEPS) is a rapid, bedside, and less invasive option for subdural hemorrhage management. Proper procedure planning and understanding of the relevant vascular anatomy is important for minimizing complications and future procedures. Case Description: We describe a case where following placement of a SEPS, there was immediate development of a new dural arteriovenous fistula (dAVF) between the middle meningeal artery (MMA) and middle meningeal vein. Angiography confirmed site of shunting to be at the proximity of the twist drill hole placement. Subsequent MMA embolization was performed and follow-up MRI confirmed resolution of the dAVF. Conclusion: SEPS-associated dAVF is an underreported complication with potential long-term consequences. This case describes the complication and advocates avoiding SEPS anterior to the coronal suture.

BACKGROUND: Hypertonic saline (HTS) and mannitol are effective in reducing intracranial pressure (ICP) after severe traumatic brain injury (TBI). However, their simultaneous effect on the cerebral perfusion pressure (CPP) and ICP has not been studied rigorously. OBJECTIVE: To determine the difference in effects of HTS and mannitol on the combined burden of high ICP and low CPP in patients with severe TBI. METHODS: We performed a case–control study using prospectively collected data from the New York State TBI-trac® database (Brain Trauma Foundation, New York, New York). Patients who received only 1 hyperosmotic agent, either mannitol or HTS for raised ICP, were included. Patients in the 2 groups were matched (1:1 and 1:2) for factors associated with 2-wk mortality: age, Glasgow Coma Scale score, pupillary reactivity, hypotension, abnormal computed tomography scans, and craniotomy. Primary endpoint was the combined burden of ICP(high) (> 25 mm Hg) and CPP(low) (

Sport-related concussion has garnered increasing scientific attention and research over the last decade. Collegiate student-athletes represent an important cohort in this field. As such, the Pac-12 CARE-Affiliated Program (CAP) was formed in 2017 as a regional hub of the Concussion Assessment, Research and Education (CARE) consortium. CAP is multisite, prospective, longitudinal study that aims to improve student-athlete health by identifying factors associated with concussion incidence and recovery and using this knowledge to inform best clinical practices and policy decisions. CAP employed a staggered rollout across the Pac-12, with the first four institutions enrolling in fall 2018. After receiving institutional review board (IRB) approval, these institutions began consenting student-athletes to share clinical concussion and baseline data for research purposes. Athletes completed baseline testing that included a medical questionnaire, concussion history and a battery for clinical concussion assessments. Concussed student-athletes were given the same battery of assessments in addition to full injury and return to play reports. Clinicians at each university worked with a data coordinator to ensure appropriate reporting, and the Pac-12 Concussion Coordinating Unit at the University of Colorado Boulder provided oversight for quality control of the data study wide. During year 1, CAP consented 2181 student-athletes and tracked 140 concussions. All research was conducted with the appropriate IRB approval across the participating Pac-12 institutions. Data security and dissemination are managed by the Presagia Sports Athlete Electronic Health Record software (Montreal, Quebec, Canada) and QuesGen Systems (San Francisco, California, USA).

It is widely appreciated that the spectrum of traumatic brain injury (TBI), mild through severe, contains distinct clinical presentations, variably referred to as subtypes, phenotypes, and/or clinical profiles. As part of the Brain Trauma Blueprint TBI State of the Science, we review the current literature on TBI phenotyping with an emphasis on unsupervised methodological approaches, and describe five phenotypes that appear similar across reports. However, we also find the literature contains divergent analysis strategies, inclusion criteria, findings, and use of terms. Further, whereas some studies delineate phenotypes within a specific severity of TBI, others derive phenotypes across the full spectrum of severity. Together, these facts confound direct synthesis of the findings. To overcome this, we introduce PhenoBench, a freely available code repository for the standardization and evaluation of raw phenotyping data. With this review and toolset, we provide a pathway toward robust, data-driven phenotypes that can capture the heterogeneity of TBI, enabling reproducible insights and targeted care.

Context Concussion underreporting leads to delays in diagnosis and treatment, prolonging recovery time. Athletes' self-reporting of concussion symptoms, therefore, reduces risk. Objective To evaluate the effectiveness of 3 concussion-education programs in improving concussion-reporting intention. Design Randomized controlled clinical trial. Setting Three high schools in California. Patients or Other Participants A total of 118 male football players (age = 14.88 ± 1.19 years). Intervention(s) Participants were randomly assigned to receive concussion education via CrashCourse (CC), Centers for Disease Control and Prevention (CDC) video education materials (CDC-Vi), or CDC written education materials (CDC-Wr). Main Outcome Measure(s) The primary outcome was concussion-reporting intention, which was assessed at baseline, immediately after education, and at 1-month follow-up. Secondary outcomes were concussion knowledge, concussion-reporting attitudes, perceived concussion-reporting norms, and perceived behavioral control. Results Across all education formats, a total sample of athletes improved in concussion-reporting intention at immediate and 1-month follow-ups (mean improvements = 6.8% and 11.4%, respectively; F4,224 = 11.1, P < .001). Similar findings were observed across all education formats in secondary analyses examining knowledge, attitudes, and perceived behavioral control. However, we noted differences in concussion-reporting intention by education format and time (F4,224 = 2.8, P = .03). Post hoc analysis showed that athletes who received CC had increased concussion-reporting intentions at immediate and 1-month follow-ups (baseline = 4.7, immediate follow-up = 6.1, 1-month follow-up = 6.0; F16,61.1 = 6.1, P = .007) compared with increases only at 1-month follow-up for CDC-Vi (baseline = 4.3, immediate follow-up = 5.2, 1-month follow-up = 5.8; F1.6,61.6 = 8.4, P = .001) and no improvement for CDC-Wr (P = .10). Secondary analyses indicated differences between CC and both CDC interventions in concussion knowledge and attitudes at immediate and 1-month follow-ups. We identified no differences in perceived behavioral control among interventions (F4,216 = 0.2, P = .93) or perceived concussion-reporting norms across (F4,224 = 0.3, P = .73) or among (F4,224 = 1.7, P = .15) interventions. Conclusions All athletes exhibited an improved intent to report concussions, increased concussion knowledge, better concussion attitudes, and more perceived behavioral control at both immediate and 1-month follow-ups. However, athletes randomized to receive CC reported a greater intent to report concussion, more knowledge, and improved concussion-reporting attitudes when compared with those who received CDC-Vi and CDC-Wr.

Background: There is heterogeneity in neurosensory alterations following mild traumatic brain injury. Commonly assessed neurosensory symptoms following head injury include symptom reports and measures of oculomotor impairment, auditory changes, and vestibular impairment. Hypothesis/Purpose: Neurosensory alterations are prevalent acutely following mild traumatic brain injury secondary to blunt head trauma during collegiate varsity sports and may vary by sex and sport. Study Design: Retrospective study of a large collegiate athletic database. Methods: Analyses were performed using an established single University dataset of 177 male and female collegiate varsity athletes who were diagnosed with concussion/mild traumatic brain injury between September 2013 and October 2019. Descriptive and comparative analyses were performed on individual and grouped acute concussion assessments pertaining to neurosensory alterations obtained within 72 h of injury using components of the Sports Concussion Assessment Tool Version 5 and Vestibular/Ocular-Motor Screening. Results: Females had significantly more abnormal smooth pursuit (p-value: 0.045), convergence (p-value: 0.031), and visual motion sensitivity tests results (p-value: 0.023) than males. There were no differences in neurosensory alterations when grouped by overall auditory, vestibular, or oculomotor impairments. The majority of sports-related concussions occurred during football (50, 28.25%), wrestling (21, 11.86%), water polo (15, 8.47%), and basketball (14, 7.91%). Abnormal vestibular assessments were high in these top four sports categories, but statistically significant differences in overall auditory, vestibular, or oculomotor impairments were not reached by individual sport. However, water polo players had higher abnormal individual assessments related to balance reports on the sideline (60.00%, p-value: 0.045) and in the clinic setting (57.14%, p-value: 0.038) as compared to all other sports. Conclusion: While neurosensory alterations are prevalent in both male and female athletes acutely post-concussion, females have a higher incidence of abnormalities in smooth pursuit, convergence, and visual motion sensitivity and may benefit from early rehabilitation.

Background Traumatic brain injury (TBI) often results in elevations in intracranial pressure (ICP) that are refractory to standard therapies. Several studies have investigated the utility of external lumbar drainage (ELD) in this setting. Objective To evaluate the safety and efficacy of ELD or lumbar puncture with regard to immediate effect on ICP, durability of the effect on ICP, complications, and neurological outcomes in adults with refractory traumatic intracranial hypertension. Methods A systematic review and meta-analysis were conducted beginning with a comprehensive search of PubMed/EMBASE. Two investigators reviewed studies for eligibility and extracted data. The strength of evidence was evaluated using GRADE methodology. Random-effects meta-analyses were performed to calculate pooled estimates. Results Nine articles detailing 6 studies (N = 110) were included. There was moderate evidence that ELD has a significant immediate effect on ICP; the pooled effect size was -19.5 mmHg (95% CI -21.0 to -17.9 mmHg). There was low evidence to indicate a durable effect of ELD on ICP up to at least 24 h following ELD. There was low evidence to indicate that ELD was safe and associated with a low rate of clinical cerebral herniation or meningitis. There was very low evidence pertaining to neurological outcomes. Conclusion Given preliminary data indicating potential safety and feasibility in highly selected cases, the use of ELD in adults with severe TBI and refractory intracranial hypertension in the presence of open basal cisterns and absence of large focal hematoma merits further high-quality investigation; the ideal conditions for potential application remain to be determined.

Background Current guidelines for the treatment of adult severe traumatic brain injury (sTBI) consist of high-quality evidence reports, but they are no longer accompanied by management protocols, as these require expert opinion to bridge the gap between published evidence and patient care. We aimed to establish a modern sTBI protocol for adult patients with both intracranial pressure (ICP) and brain oxygen monitors in place. Methods Our consensus working group consisted of 42 experienced and actively practicing sTBI opinion leaders from six continents. Having previously established a protocol for the treatment of patients with ICP monitoring alone, we addressed patients who have a brain oxygen monitor in addition to an ICP monitor. The management protocols were developed through a Delphi-method-based consensus approach and were finalized at an in-person meeting. Results We established three distinct treatment protocols, each with three tiers whereby higher tiers involve therapies with higher risk. One protocol addresses the management of ICP elevation when brain oxygenation is normal. A second addresses management of brain hypoxia with normal ICP. The third protocol addresses the situation when both intracranial hypertension and brain hypoxia are present. The panel considered issues pertaining to blood transfusion and ventilator management when designing the different algorithms. Conclusions These protocols are intended to assist clinicians in the management of patients with both ICP and brain oxygen monitors but they do not reflect either a standard-of-care or a substitute for thoughtful individualized management. These protocols should be used in conjunction with recommendations for basic care, management of critical neuroworsening and weaning treatment recently published in conjunction with the Seattle International Brain Injury Consensus Conference. Electronic supplementary material The online version of this article (10.1007/s00134-019-05900-x) contains supplementary material, which is available to authorized users.

BACKGROUNDThe Brain Trauma Foundation has developed treatment guidelines for the care of patients with acute traumatic brain injury. The Adam Williams Initiative is a program established to provide education and resources to encourage hospitals across the United States to incorporate the guidelines into practice.OBJECTIVETo explore the relationship in hospitals between participation in the Adam Williams Initiative and adherence to the Brain Trauma Foundation guidelines for patients with acute traumatic brain injury.METHODHospitals that participated in the Adam Williams Initiative entered data into an online tracking system of patients with traumatic brain injury for at least 2 years after the initial site training. Data included baseline hospital records and daily records on hospital care of patients with traumatic brain injury, including blood pressure, intracranial pressure, cerebral perfusion pressure, oxygenation, and other data relevant to the 15 key metrics in the Brain Trauma Foundation guidelines.RESULTSThe 16 hospitals funded by the Adam Williams Initiative had good overall adherence to the 15 key metrics of the recommendations detailed in the Brain Trauma Foundation guidelines. Variability in results was primarily due to data collection methods and analysis.CONCLUSIONSThe Adam Williams Initiative helps promote adherence to the Brain Trauma Foundation guidelines for hospital care of patients with traumatic brain injury by providing a platform for developing and standardizing best practices. Participation in the initiative is associated with high adherence to clinical guidelines, a situation that may subsequently improve care and outcomes for patients with traumatic brain injury.

When the fourth edition of the Brain Trauma Foundation's Guidelines for the Management of Severe Traumatic Brain Injury were finalized in late 2016, it was known that the results of the RESCUEicp (Trial of Decompressive Craniectomy for Traumatic Intracranial Hypertension) randomized controlled trial of decompressive craniectomy would be public after the guidelines were released. The guideline authors decided to proceed with publication but to update the decompressive craniectomy recommendations later in the spirit of "living guidelines," whereby topics are updated more frequently, and between new editions, when important new evidence is published. The update to the decompressive craniectomy chapter presented here integrates the findings of the RESCUEicp study as well as the recently published 12-mo outcome data from the DECRA (Decompressive Craniectomy in Patients With Severe Traumatic Brain Injury) trial. Incorporation of these publications into the body of evidence led to the generation of 3 new level-IIA recommendations; a fourth previously presented level-IIA recommendation remains valid and has been restated. To increase the utility of the recommendations, we added a new section entitled Incorporating the Evidence into Practice. This summary of expert opinion provides important context and addresses key issues for practitioners, which are intended to help the clinician utilize the available evidence and these recommendations. The full guideline can be found at: https://braintrauma.org/guidelines/guidelines-for-the-management-of-severe-tbi-4th-ed#/.

Aim: Postconcussion symptom-rating scales are frequently used concussion assessment tools that do not align directly with new expert, consensus-based concussion subtype classification systems. This may result in delays in concussion diagnosis, subspecialty referral and rehabilitative strategies. Objective: To determine the representation of subtype-directed symptomatology in common postconcussion symptom-rating scales. Methods: Literature review and expert consensus were used to compile commonly used concussion symptom-rating scales. Statistics were generated to describe the degree of representation of the consensus symptom set. Results: The percentage of symptoms representing each subtype/associated condition is low overall (15–26%). The ocular-motor (11%) and vestibular subtypes (19%) and cervical strain (5%)-associated condition were the most under-represented and also had the greatest unmet needs. Conclusion: Concussion subtypes do not have equal representation on commonly used concussion symptom-rating scales. There is a need for a subtype-directed symptom assessment to allow for increased accuracy of diagnosis and to guide management.

Brain injury; Head trauma; Algorithm Daño cerebral; Trauma en la cabeza; Algoritmo Lesió cerebral; Trauma al cap; Algoritme Background: Management algorithms for adult severe traumatic brain injury (sTBI) were omitted in later editions of the Brain Trauma Foundation’s sTBI Management Guidelines, as they were not evidence-based. Methods: We used a Delphi-method-based consensus approach to address management of sTBI patients undergoing intracranial pressure (ICP) monitoring. Forty-two experienced, clinically active sTBI specialists from six continents comprised the panel. Eight surveys iterated queries and comments. An in-person meeting included whole- and small-group discussions and blinded voting. Consensus required 80% agreement. We developed heatmaps based on a traffic-light model where panelists’ decision tendencies were the focus of recommendations. Results: We provide comprehensive algorithms for ICP-monitor-based adult sTBI management. Consensus established 18 interventions as fundamental and ten treatments not to be used. We provide a three-tier algorithm for treating elevated ICP. Treatments within a tier are considered empirically equivalent. Higher tiers involve higher risk therapies. Tiers 1, 2, and 3 include 10, 4, and 3 interventions, respectively. We include inter-tier considerations, and recommendations for critical neuroworsening to assist the recognition and treatment of declining patients. Novel elements include guidance for autoregulation-based ICP treatment based on MAP Challenge results, and two heatmaps to guide (1) ICP-monitor removal and (2) consideration of sedation holidays for neurological examination. Conclusions: Our modern and comprehensive sTBI-management protocol is designed to assist clinicians managing sTBI patients monitored with ICP-monitors alone. Consensus-based (class III evidence), it provides management recommendations based on combined expert opinion. It reflects neither a standard-of-care nor a substitute for thoughtful individualized management. We thank our financial supporters who include Adler/Geirsch Attorney at Law, the American Association of Neurological Surgeons/Congress of Neurological Surgeons Section on Neurotrauma and Critical Care, Bard, the Brain Trauma Foundation, DePuy, Hemedex, Integra, the Neurointensive Care Section of the European Society of Intensive Care Medicine, Neurosurgical Society of Australasia, Medtronic, Moberg Research, Natus, Neuroptics, Raumedic, Sophysa, Stryker, and Zoll.

BACKGROUND Concussion is a heterogeneous mild traumatic brain injury (mTBI) characterized by a variety of symptoms, clinical presentations, and recovery trajectories. By thematically classifying the most common concussive clinical presentations into concussion subtypes (cognitive, ocular-motor, headache/migraine, vestibular, and anxiety/mood) and associated conditions (cervical strain and sleep disturbance), we derive useful definitions amenable to future targeted treatments. OBJECTIVE To use evidence-based methodology to characterize the 5 concussion subtypes and 2 associated conditions and report their prevalence in acute concussion patients as compared to baseline or controls within 3 d of injury. METHODS A multidisciplinary expert workgroup was established to define the most common concussion subtypes and their associated conditions and select clinical questions related to prevalence and recovery. A literature search was conducted from January 1, 1990 to November 1, 2017. Two experts abstracted study characteristics and results independently for each article selected for inclusion. A third expert adjudicated disagreements. Separate meta-analyses were conducted to do the following: 1) examine the prevalence of each subtype/associated condition in concussion patients using a proportion, 2) assess subtype/associated conditions in concussion compared to baseline/uninjured controls using a prevalence ratio, and 3) compare the differences in symptom scores between concussion subtypes and uninjured/baseline controls using a standardized mean difference (SMD). RESULTS The most prevalent concussion subtypes for pediatric and adult populations were headache/migraine (0.52; 95% CI = 0.37, 0.67) and cognitive (0.40; 95% CI = 0.25, 0.55), respectively. In pediatric patients, the prevalence of the vestibular subtype was also high (0.50; 95% CI = 0.40, 0.60). Adult patients were 4.4, 2.9, and 1.7 times more likely to demonstrate cognitive, vestibular, and anxiety/mood subtypes, respectively, as compared with their controls (P

Traumatic brain injury (TBI) is a major cause of morbidity and mortality throughout the world. Mild TBI, which is typically defined by Glasgow Coma Scale score ≥13, accounts for the vast majority of all TBIs, particularly in the setting of sports-related injuries. The terms concussion and TBI are often used interchangeably, both in the medical literature and in clinical care of this patient population. However, the lack of clearly defined definitions of these terms often leads to confusion, and this confusion may lead to delayed diagnosis and inconsistent management of affected patients. Here, we review the current terminology and classification of mild TBI and concussion. We will also discuss recent efforts to stratify these injuries into clinically relevant subtypes or profiles that are both diagnostic- and treatment-targeted.

Traumatic brain injury (TBI) is a major cause of morbidity and mortality throughout the world. Mild TBI, which is typically defined by Glasgow Coma Scale score ≥13, accounts for the vast majority of all TBIs, particularly in the setting of sports-related injuries. The terms concussion and TBI are often used interchangeably, both in the medical literature and in clinical care of this patient population. However, the lack of clearly defined definitions of these terms often leads to confusion, and this confusion may lead to delayed diagnosis and inconsistent management of affected patients. Here, we review the current terminology and classification of mild TBI and concussion. We will also discuss recent efforts to stratify these injuries into clinically relevant subtypes or profiles that are both diagnostic- and treatment-targeted.

OBJECT Increased intracranial pressure (ICP) in patients with traumatic brain injury (TBI) is associated with a higher mortality rate and poor outcome. Mannitol and hypertonic saline (HTS) have both been used to treat high ICP, but it is unclear which one is more effective. Here, the authors compare the effect of mannitol versus HTS on lowering the cumulative and daily ICP burdens after severe TBI. METHODS The Brain Trauma Foundation TBI-trac New York State database was used for this retrospective study. Patients with severe TBI and intracranial hypertension who received only 1 type of hyperosmotic agent, mannitol or HTS, were included. Patients in the 2 groups were individually matched for Glasgow Coma Scale score (GCS), pupillary reactivity, craniotomy, occurrence of hypotension on Day 1, and the day of ICP monitor insertion. Patients with missing or erroneous data were excluded. Cumulative and daily ICP burdens were used as primary outcome measures. The cumulative ICP burden was defined as the total number of days with an ICP of > 25 mm Hg, expressed as a percentage of the total number of days of ICP monitoring. The daily ICP burden was calculated as the mean daily duration of an ICP of > 25 mm Hg, expressed as the number of hours per day. The numbers of intensive care unit (ICU) days, numbers of days with ICP monitoring, and 2-week mortality rates were also compared between the groups. A 2-sample t-test or chi-square test was used to compare independent samples. The Wilcoxon signed-rank or Cochran-Mantel-Haenszel test was used for comparing matched samples. RESULTS A total of 35 patients who received only HTS and 477 who received only mannitol after severe TBI were identified. Eight patients in the HTS group were excluded because of erroneous or missing data, and 2 other patients did not have matches in the mannitol group. The remaining 25 patients were matched 1:1. Twenty-four patients received 3% HTS, and 1 received 23.4% HTS as bolus therapy. All 25 patients in the mannitol group received 20% mannitol. The mean cumulative ICP burden (15.52% [HTS] vs 36.5% [mannitol]; p = 0.003) and the mean (± SD) daily ICP burden (0.3 ± 0.6 hours/day [HTS] vs 1.3 ± 1.3 hours/day [mannitol]; p = 0.001) were significantly lower in the HTS group. The mean (± SD) number of ICU days was significantly lower in the HTS group than in the mannitol group (8.5 ± 2.1 vs 9.8 ± 0.6, respectively; p = 0.004), whereas there was no difference in the numbers of days of ICP monitoring (p = 0.09). There were no significant differences between the cumulative median doses of HTS and mannitol (p = 0.19). The 2-week mortality rate was lower in the HTS group, but the difference was not statistically significant (p = 0.56). CONCLUSIONS HTS given as bolus therapy was more effective than mannitol in lowering the cumulative and daily ICP burdens after severe TBI. Patients in the HTS group had significantly lower number of ICU days. The 2-week mortality rates were not statistically different between the 2 groups.

Background: Data evaluating the role of exercise in patients with a concussion are contradictory. Studies have reported improvement in the Post-Concussion Symptom Scale (PCSS) score, whereas others showed no effect on the PCSS score. Purpose: To conduct a systematic review and meta-analysis on the role of physical exercise on different outcomes in patients with a concussion. Study Design: Systematic review and meta-analysis. Methods: A search of 5 databases from the earliest available date to September 30, 2016, and a hand search of a few articles were performed. Trial registries were reviewed, and authors of multiple studies were contacted to find additional published or unpublished studies. Randomized controlled trials (RCTs), cohort studies, and before and after (pre-post) studies evaluating the effect of physical exercise, compared with control, in patients with a concussion or mild traumatic brain injury were included. Results: The search generated 1096 studies. Of these, 14 studies (5 RCTs, 1 propensity score matching study, 3 cohort studies, and 5 before and after studies) met our inclusion criteria. Exercise significantly decreased the PCSS score (mean difference, −13.06; 95% CI, −16.57 to −9.55; P < .00001; I2 = 44%), percentage of patients with symptoms of a concussion (risk ratio, 0.74; 95% CI, 0.63 to 0.86; P = .0001; I2 = 0%), and days off work (17.7 days vs 32.2 days, respectively; P < .05) compared with control. Exercise improved the reaction time (standard mean difference, –0.43; 95% CI, −0.80 to −0.06; P = .02) component of the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) score without affecting the Balance Error Scoring System (BESS) score and neuropsychological parameters. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) scores were moderate for the PCSS, symptoms, ImPACT, BESS, and neuropsychological tests. Conclusion: Physical exercise appears to improve the PCSS score and symptoms in patients with a concussion. A high-quality RCT evaluating different intensities of exercise at different time points, for different durations after a concussion, for different races/ethnicities, and for sex needs to be conducted to evaluate a clear effect of exercise in patients with a concussion.

Human visual tracking performance is known to be reduced with an increase of the target's speed and oscillation frequency, but changes in brain states following a concussion may alter these frequency responses. The goal of this study was to characterize and compare frequency-dependent smooth pursuit velocity degradation in normal subjects and patients who had chronic postconcussion symptoms, and also examine cases of acutely concussed patients. Eye movements were recorded while subjects tracked a target that moved along a circular trajectory of 10° radius at 0.33, 0.40, or 0.67 Hz. Performance was characterized by the gain of smooth pursuit velocity, with reduced gain indicating reduced performance. The difference between normal and chronic patient groups in the pattern of decrease in the gain of horizontal smooth pursuit velocity as a function of the stimulus frequency reflected patients performing more poorly than normal subjects at 0.4 Hz while both groups performing similarly at 0.33 or 0.67 Hz. The performance of acute patients may represent yet another type of frequency response. The findings suggest that there may be ranges of stimulus frequencies that differentiate the effects of concussion from normal individuals.

BACKGROUND: Currently, there is no evidence-based definition for concussion that is being uniformly applied in clinical and research settings. OBJECTIVE: To conduct a systematic review of the highest-quality literature about concussion and to assemble evidence about the prevalence and associations of key indicators of concussion. The goal was to establish an evidence-based foundation from which to derive, in future work, a definition, diagnostic criteria, and prognostic indicators for concussion. METHODS: Key questions were developed, and an electronic literature search from 1980 to 2012 was conducted to acquire evidence about the prevalence of and associations among signs, symptoms, and neurologic and cognitive deficits in samples of individuals exposed to potential concussive events. Included studies were assessed for potential for bias and confound and rated as high, medium, or low potential for bias and confound. Those rated as high were excluded from the analysis. Studies were further triaged on the basis of whether the definition of a case of concussion was exclusive or inclusive; only those with wide, inclusive case definitions were used in the analysis. Finally, only studies reporting data collected at fixed time points were used. For a study to be included in the conclusions, it was required that the presence of any particular sign, symptom, or deficit be reported in at least 2 independent samples. RESULTS: From 5437 abstracts, 1362 full-text publications were reviewed, of which 231 studies were included in the final library. Twenty-six met all criteria required to be used in the analysis, and of those, 11 independent samples from 8 publications directly contributed data to conclusions. Prevalent and consistent indicators of concussion are (1) observed and documented disorientation or confusion immediately after the event, (2) impaired balance within 1 day after injury, (3) slower reaction time within 2 days after injury, and/or (4) impaired verbal learning and memory within 2 days after injury. CONCLUSION: The results of this systematic review identify the consistent and prevalent indicators of concussion and their associations, derived from the strongest evidence in the published literature. The product is an evidence-based foundation from which to develop diagnostic criteria and prognostic indicators.

We tested whether reduced cognitive function associated with mild traumatic brain injury (mTBI) and sleep deprivation can be detected and distinguished using indices of predictive visual tracking. A circular visual tracking test was given to 13 patients with acute mTBI (recruited within 2 weeks of injury), 127 normal control subjects, and 43 healthy subjects who were fatigued by 26-hour sleep deprivation. Eye movement was monitored with video-oculography. In the mTBI-related portion of the study, visual tracking performance of acute mTBI patients was significantly worse than normal subjects (p0.001). In the sleep-deprivation-related portion of the study, no change was detected between the two baseline measures separated by 2 to 3 weeks, but the 26-hour sleep deprivation significantly degraded the visual tracking performance (p0.001). The mTBI subjects had substantially worse visual tracking than sleep-deprived subjects that could also be identified with different visual tracking indices, indicating possible different neurophysiological mechanisms. Results suggest that cognitive impairment associated with mTBI and fatigue may be triaged with the aid of visual tracking measures.

BACKGROUND: Fatigue due to sleep restriction places individuals at elevated risk for accidents, degraded health, and impaired physical and mental performance. Early detection of fatigue-related performance decrements is an important component of injury prevention and can help to ensure optimal performance and mission readiness. This study used a predictive visual tracking task and a computer-based measure of attention to characterize fatigue-related attention decrements in healthy Army personnel during acute sleep deprivation. METHODS: Serving as subjects in this laboratory-based study were 87 male and female service members between the ages of 18 and 50 with no history of brain injury with loss of consciousness, substance abuse, or significant psychiatric or neurologic diagnoses. Subjects underwent 26 h of sleep deprivation, during which eye movement measures from a continuous circular visual tracking task and attention measures (reaction time, accuracy) from the Attention Network Test (ANT) were collected at baseline, 20 h awake, and between 24 to 26 h awake. RESULTS: Increases in the variability of gaze positional errors (46-47%), as well as reaction time-based ANT measures (9-65%), were observed across 26 h of sleep deprivation. Accuracy of ANT responses declined across this same period (11%). DISCUSSION: Performance measures of predictive visual tracking accurately reflect impaired attention due to acute sleep deprivation and provide a promising approach for assessing readiness in personnel serving in diverse occupational areas, including flight and ground support crews. Language: en