Committee on Surgical Combat Casualty Care position statement: Neurosurgical capability for the optimal management of traumatic brain injury during deployed operations.

BACKGROUND: Experiences over the last three decades of war have demonstrated a high incidence of traumatic brain injury (TBI) resulting in a persistent need for a neurosurgical capability within the deployed theater of operations. Despite this, no doctrinal requirement for a deployed neurosurgical capability exists. Through an iterative process, the Joint Trauma System Committee on Surgical Combat Casualty Care (CoSCCC) developed a position statement to inform medical and nonmedical military leaders about the risks of the lack of a specialized neurosurgical capability. METHODS: The need for deployed neurosurgical capability position statement was identified during the spring 2021 CoSCCC meeting. A triservice working group of experienced forward-deployed caregivers developed a preliminary statement. An extensive iterative review process was then conducted to ensure that the intended messaging was clear to senior medical leaders and operational commanders. To provide additional context and a civilian perspective, statement commentaries were solicited from civilian clinical experts including a recently retired military trauma surgeon boarded in neurocritical care, a trauma surgeon instrumental in developing the Brain Injury Guidelines, a practicing neurosurgeon with world-renowned expertise in TBI, and the chair of the Committee on Trauma. RESULTS: After multiple revisions, the position statement was finalized, and approved by the CoSCCC membership in February 2023. Challenges identified include (1) military neurosurgeon attrition, (2) the lack of a doctrinal neurosurgical capabilities requirement during deployed combat operations, and (3) the need for neurosurgical telemedicine capability and in-theater computed tomography scans to triage TBI casualties requiring neurosurgical care. CONCLUSION: Challenges identified regarding neurosurgical capabilities within the deployed trauma system include military neurosurgeon attrition and the lack of a doctrinal requirement for neurosurgical capability during deployed combat operations. To mitigate risk to the force in a future peer-peer conflict, several evidence-based recommendations are made. The solicited civilian commentaries strengthen these recommendations by putting them into the context of civilian TBI management. This neurosurgical capabilities position statement is intended to be a forcing function and a communication tool to inform operational commanders and military medical leaders on the use of these teams on current and future battlefields. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level V.

Military Traumatic Brain Injury: The History, Impact, and Future.

This review examines how lessons learned from United States military conflicts, beginning with the United States Civil War through the engagements in Iraq and Afghanistan, have shaped current traumatic brain injury (TBI) care in the United States military, influenced congressional mandates and directives, and led to best practices in caring for the warfighter. Prior to the most recent war, emphasis was placed on improving the surgical and medical care of service members (SM) with severe and especially penetrating brain injuries. However, during the Iraq and Afghanistan conflicts, also known as the Global War on Terrorism (GWOT), blast injury from improvised explosive devices most often caused mild TBI (mTBI), an injury that was not always recognized and was labelled the "signature wound" of the GWOT. This has led to extensive research on objective diagnostic technologies for mTBI, the association of mTBI with post-traumatic stress disorder (PTSD), and the long term consequences of mTBI. Here we summarize the key findings and most important advances from those efforts, and discuss the way forward regarding future military conflicts.

Molecular and Diffusion Tensor Imaging Biomarkers of Traumatic Brain Injury: Principles for Investigation and Integration.

The last 20 years have seen the advent of new technologies that enhance the diagnosis and prognosis of traumatic brain injury (TBI). There is recognition that TBI affects the brain beyond initial injury, in some cases inciting a progressive neuropathology that leads to chronic impairments. Medical researchers are now searching for biomarkers to detect and monitor this condition. Perhaps the most promising developments are in the biomolecular and neuroimaging domains. Molecular assays can identify proteins indicative of neuronal injury and/or degeneration. Diffusion imaging now allows sensitive evaluations of the brain's cellular microstructure. As the pace of discovery accelerates, it is important to survey the research landscape and identify promising avenues of investigation. In this review, we discuss the potential of molecular and diffusion tensor imaging (DTI) biomarkers in TBI research. Integration of these technologies could advance models of disease prognosis, ultimately improving care. To date, however, few studies have explored relationships between molecular and DTI variables in patients with TBI. Here, we provide a short primer on each technology, review the latest research, and discuss how these biomarkers may be incorporated in future studies.

Military TBI-What civilian primary care providers should know.

In June 2019, the Department of Veterans Affairs (VA) launched the VA Mission Act, which expanded veterans' health-care access to the private sector. Since civilian primary care providers may see more veterans in their practice, it will be important to understand the unique experiences, comorbidities, and culture of this population in order to provide optimal care. Military service members (SMs) are at an increased risk for traumatic brain injury (TBI), and comorbidities, such as post traumatic stress disorder (PTSD), increasing the likelihood of prolonged symptoms. Military training and repetitive low-level blast exposure may cause symptoms similar to TBI or increase long-term negative effects in SMs. Military culture often has a strong influence in this population. Those who serve in the military identify with military values and have a strong team mentality, which places emphasis on the mission above all else, not accepting defeat, and not ever leaving a fellow SM behind. These values can impact the way a SM/veteran seeks care and/or communicates with his or her health-care provider. Taking a detailed history to understand how these factors apply, as well as screening for mental health comorbidities, are recommended. Understanding the military cultural influences can assist in promoting a stronger therapeutic alliance and encourage more open communication. Ultimately, it is the trusting and respectful relationship between the SM/veteran and the provider that will determine the most effective treatment and result in the most effective resolution of TBI and comorbid symptoms.

Estimates of Long-Term Disability Among US Service Members With Traumatic Brain Injuries.

BACKGROUND: Traumatic brain injury (TBI) is a significant health issue in the US military. The purpose of this study was to estimate the probability of long-term disability among hospitalized service members (SMs) with TBIs, using the South Carolina Traumatic Brain Injury and Follow-up Registry (SCTBIFR) model developed on civilian hospitalized patients. METHODS: We identified military patients in military or civilian hospitals or theater level 3 to 5 military treatment facilities (MTFs) whose first TBI occurred between October 1, 2013, and September 30, 2015. TBI-related disability at 1-year post-hospital discharge was estimated using regression coefficients from the SCTBIFR. RESULTS: Among the identified 4877 SMs, an estimated 65.6% of SMs with severe TBI, 56.2% with penetrating TBI, 31.4% with moderate TBI, and 12.0% with mild TBI are predicted to develop long-term disability. TBI patients identified at theater level 4 and 5 MTFs had an average long-term disability rate of 56.9% and 61.1%, respectively. In total, we estimate that 25.2% of all SMs hospitalized with TBI will develop long-term disability. CONCLUSION: Applying SCTBIFR long-term probability estimates to US SMs with TBIs provides useful disability estimates to inform providers and health systems on the likelihood that particular subgroups of TBI patients will require continued support and long-term care.

Military Acute Concussion Evaluation: A Report on Clinical Usability, Utility, and User's Perceived Confidence.

The signs and symptoms of concussion may not always be clear. Therefore, the Military Acute Concussion Evaluation (MACE) tool was created to help deployed medics and corpsmen identify concussions, particularly in deployed settings. Since 2008, the MACE has been updated multiple times, but each new version of the tool is more complex and takes longer to complete. The objective of this study was to assess the usability, utility, and perceived confidence among military healthcare providers for the latest version, MACE 2. Therefore, a semi-structured interview, including Likert-scale and open-ended questions, was conducted among military healthcare providers at Landstuhl Regional Medical Center in order to assess the usability, utility and perceived confidence of the MACE 2. All of the providers had completed a training course on the MACE 2 and had used it for at least 3 months in their clinics. A total of 28 participants were recruited, including 22 medics, two physicians, three nurses, and one physician assistant. Average scores of usability, utility, and confidence were 5.7, 6.6, and 6.3, respectively, with 7.0 being the most positive score, and thus indicating positive assessments in all categories. The open-ended questions revealed high usability and confidence and the desire for additional training on the tool. In conclusion, despite the increased complexity and duration of the MACE 2 compared with the previous version of this tool, military providers and army medics found the new MACE 2 very useable and had a high degree of confidence in its performance.

The Prehospital Evaluation and Care of Moderate/Severe TBI in the Austere Environment.

Increased resource constraints secondary to a smaller medical footprint, prolonged evacuation times, or overwhelming casualty volumes all increase the challenges of effective management of traumatic brain injury (TBI) in the austere environment. Prehospital providers are responsible for the battlefield recognition and initial management of TBI. As such, targeted education is critical to efficient injury recognition, promoting both provider readiness and improved patient outcomes. When austere conditions limit or prevent definitive treatment, a comprehensive understanding of TBI pathophysiology can help inform acute care and enhance prevention of secondary brain injury. Field deployable, noninvasive TBI assessment and monitoring devices are urgently needed and are currently undergoing clinical evaluation. Evidence shows that the assessment, monitoring, and treatment in the first few hours and days after injury should focus on the preservation of cerebral perfusion and oxygenation. For cases where medical management is inadequate (eg, evidence of an enlarging intracranial hematoma), guidelines have been developed for the performance of cranial surgery by nonneurosurgeons. TBI management in the austere environment will continue to be a challenge, but research focused on improving evidence-based monitoring and therapeutic interventions can help to mitigate some of these challenges and improve patient outcomes.

Association of time to craniectomy with survival in patients with severe combat-related brain injury.

OBJECTIVEIn combat and austere environments, evacuation to a location with neurosurgery capability is challenging. A planning target in terms of time to neurosurgery is paramount to inform prepositioning of neurosurgical and transport resources to support a population at risk. This study sought to examine the association of wait time to craniectomy with mortality in patients with severe combat-related brain injury who received decompressive craniectomy.METHODSPatients with combat-related brain injury sustained between 2005 and 2015 who underwent craniectomy at deployed surgical facilities were identified from the Department of Defense Trauma Registry and Joint Trauma System Role 2 Registry. Eligible patients survived transport to a hospital capable of diagnosing the need for craniectomy and performing surgery. Statistical analyses included unadjusted comparisons of postoperative mortality by elapsed time from injury to start of craniectomy, and Cox proportional hazards modeling adjusting for potential confounders. Time from injury to craniectomy was divided into quintiles, and explored in Cox models as a binary variable comparing early versus delayed craniectomy with cutoffs determined by the maximum value of each quintile (quintile 1 vs 2-5, quintiles 1-2 vs 3-5, etc.). Covariates included location of the facility at which the craniectomy was performed (limited-resource role 2 facility vs neurosurgically capable role 3 facility), use of head CT scan, US military status, age, head Abbreviated Injury Scale score, Injury Severity Score, and injury year. To reduce immortal time bias, time from injury to hospital arrival was included as a covariate, entry into the survival analysis cohort was defined as hospital arrival time, and early versus delayed craniectomy was modeled as a time-dependent covariate. Follow-up for survival ended at death, hospital discharge, or hospital day 16, whichever occurred first.RESULTSOf 486 patients identified as having undergone craniectomy, 213 (44%) had complete date/time values. Unadjusted postoperative mortality was 23% for quintile 1 (n = 43, time from injury to start of craniectomy 30-152 minutes); 7% for quintile 2 (n = 42, 154-210 minutes); 7% for quintile 3 (n = 43, 212-320 minutes); 19% for quintile 4 (n = 42, 325-639 minutes); and 14% for quintile 5 (n = 43, 665-3885 minutes). In Cox models adjusted for potential confounders and immortal time bias, postoperative mortality was significantly lower when time to craniectomy was within 5.33 hours of injury (quintiles 1-3) relative to longer delays (quintiles 4-5), with an adjusted hazard ratio of 0.28, 95% CI 0.10-0.76 (p = 0.012).CONCLUSIONSPostoperative mortality was significantly lower when craniectomy was initiated within 5.33 hours of injury. Further research to optimize craniectomy timing and mitigate delays is needed. Functional outcomes should also be evaluated.

Continuum of the United States military's traumatic brain injury care: adjusting to the changing battlefield.

Over the past 8 years, advances in the US Military Health System (MHS) have led to extensive changes in the way combat casualty care is provided to deployed service members with a traumatic brain injury (TBI). Changes include the application of cutting-edge Clinical Practice Guidelines, use of pioneering technologies, and advances in evacuation procedures. Compared with previous engagements, current operations occur on a much smaller scale, and more frequently in austere environments, such that effective medical support is increasingly challenging. In this paper, the authors describe key aspects of the current continuum of TBI care in the US military, from the point of injury through rehabilitation, with an emphasis on how emerging technologies and evidence-based Clinical Practice Guidelines assist MHS clinicians with providing the best clinical care possible in the changing battlefield.

MRI in Management of Mild TBI/Concussion in the Deployed Setting.

Magnetic resonance imaging (MRI) has specific limitations in theater and has unique requirements for its safe use with patients which require additional technician training and strict adherence to MRI-specific safety protocols. Neuroimaging is recommended for the evaluation of service members with clinical red flags new onset or persistent or worsening symptoms, and individuals whose recovery is not progressing as anticipated. This article is a brief discussion of when MRI is appropriate.

Role of Department of Defense Policies in Identifying Traumatic Brain Injuries Among Deployed US Service Members, 2001-2016.

OBJECTIVES: To examine the role of Department of Defense policies in identifying theater-sustained traumatic brain injuries (TBIs). METHODS: We conducted a retrospective study of 48 172 US military service members who sustained their first lifetime TBIs between 2001 and 2016 while deployed to Afghanistan or Iraq. We used multivariable negative binomial models to examine the changes in TBI incidence rates following the introduction of Department of Defense policies. RESULTS: Two Army policies encouraging TBI reporting were associated with an increase of 251% and 97% in TBIs identified following their implementation, respectively. Among airmen, the introduction of TBI-specific screening questions to the Post-Deployment Health Assessment was associated with a 78% increase in reported TBIs. The 2010 Department of Defense Directive Type Memorandum 09-033 was associated with another increase of 80% in the likelihood of being identified with a TBI among soldiers, a 51% increase among sailors, and a 124% increase among Marines. CONCLUSIONS: Department of Defense and service-specific policies introduced between 2006 and 2013 significantly increased the number of battlefield TBIs identified, successfully improving the longstanding problem of underreporting of TBIs.

The Biological Basis of Chronic Traumatic Encephalopathy following Blast Injury: A Literature Review.

The United States Department of Defense Blast Injury Research Program Coordinating Office organized the 2015 International State-of-the-Science meeting to explore links between blast-related head injury and the development of chronic traumatic encephalopathy (CTE). Before the meeting, the planning committee examined articles published between 2005 and October 2015 and prepared this literature review, which summarized broadly CTE research and addressed questions about the pathophysiological basis of CTE and its relationship to blast- and nonblast-related head injury. It served to inform participants objectively and help focus meeting discussion on identifying knowledge gaps and priority research areas. CTE is described generally as a progressive neurodegenerative disorder affecting persons exposed to head injury. Affected individuals have been participants primarily in contact sports and military personnel, some of whom were exposed to blast. The symptomatology of CTE overlaps with Alzheimer's disease and includes neurological and cognitive deficits, psychiatric and behavioral problems, and dementia. There are no validated diagnostic criteria, and neuropathological evidence of CTE has come exclusively from autopsy examination of subjects with histories of exposure to head injury. The perivascular accumulation of hyperphosphorylated tau (p-tau) at the depths of cortical sulci is thought to be unique to CTE and has been proposed as a diagnostic requirement, although the contribution of p-tau and other reported pathologies to the development of clinical symptoms of CTE are unknown. The literature on CTE is limited and is focused predominantly on head injuries unrelated to blast exposure (e.g., football players and boxers). In addition, comparative analyses of clinical case reports has been challenging because of small case numbers, selection biases, methodological differences, and lack of matched controls, particularly for blast-exposed individuals. Consequently, the existing literature is not sufficient to determine whether the development of CTE is associated with head injury frequency (e.g., single vs. multiple exposures) or head injury type (e.g., impact, nonimpact, blast-related). Moreover, the incidence and prevalence of CTE in at-risk populations is unknown. Future research priorities should include identifying additional risk factors, pursuing population-based longitudinal studies, and developing the ability to detect and diagnose CTE in living persons using validated criteria.

The Benefits and Risks of Energy Drinks in Young Adults and Military Service Members.

INTRODUCTION: Energy drinks (EDs) have become an integral part of the young adult, athletic, and military culture. Many athletes are convinced that EDs enhance performance, and service members as well as college students frequently use EDs as stimulants to counter sleep deprivation, or to improve academic performance. However, concerns have been raised by some military leaders about potential adverse effects of EDs. MATERIALS AND METHODS: A needs assessment survey of a convenience sample of military health care providers was conducted and identified EDs as a top knowledge need for those providers working in the area of traumatic brain injury (TBI). The instrument demonstrated high interitem consistency (Cronbach's α > .80). To further explore the state of knowledge on EDs, and to prompt further discussion of ED use and how it may related to military treatment protocols and supporting educational products, we conducted a literature review of English language publications listed in the National Library of Medicine using the search term "energy drinks" and published during the last 5 years to determine what is known about EDs in terms of their potential benefits and health risks. RESULTS: The active ingredients in most EDs are caffeine, and to a lesser extent taurine and sugars. Several reports suggest that the combination of these ingredients is more active than the caffeine alone. Despite the positive attributes of EDs, there are increasing reports of serious and potentially life-threatening side effects. Most recently there also has been a dramatic increase in the use of ED/alcohol combination drinks, and there are preliminary studies that suggest important adverse effects with this combination. A 2013 National Institutes of Health expert workshop concluded that more clinical studies are needed to clearly define the health risks associated with ED use. CONCLUSION: The needs assessment points to a desire for more ED knowledge of health providers working with TBI patients. A few key themes emerged from the exploratory literature review that can be taken into consideration when educating health providers and delivering knowledge-based resources. Adverse effects of EDs are most closely associated with the dose of caffeine consumed. In general, the combination of ED with alcohol should be avoided because the ED can mask the level of intoxication, and the combination may be associated with increased risk-taking behavior. Overall, the risks and benefits of EDs remain controversial and good-quality long-term clinical trials are needed to inform policymaking, regulation, and the development of prevention and treatment resources.

Military Deployment May Increase the Risk for Traumatic Brain Injury Following Deployment.

OBJECTIVE: To compare rates of traumatic brain injury (TBI) diagnosis before and after overseas military deployment. DESIGN: We conducted a retrospective examination of a cohort of 119 353 active duty US military service members (Army, Navy, Air Force, and Marines) whose first lifetime overseas deployment began at any time between January 1, 2011, and December 31, 2011, and lasted at least for 30 days. For this cohort, TBI diagnoses were examined during the 76 weeks prior to deployment, during deployment, and 76 weeks following the end of deployment. MAIN MEASURES: 4-week rates of TBI diagnosis. RESULTS: The risk of being diagnosed with TBI within 4 weeks after returning from deployment was 8.4 times higher than the average risk before deployment. The risk gradually decreased thereafter up to 40 weeks postdeployment. However, during the 41 to 76 weeks following deployment, risk stabilized but remained on average 1.7 times higher than before deployment. CONCLUSION: An increased rate of TBI diagnosis following deployment was identified, which may be partly due to delayed diagnosis of TBIs that occurred while service members were deployed. Also, the increased rate may partly be due to riskier behaviors of service members following deployment that results in an increased occurrence of TBIs.

Traumatic brain injury in the US military: epidemiology and key clinical and research programs.

Traumatic brain injury (TBI), and particularly concussion, is a major concern for the U.S. Military because of the associated short term disability, long term cognitive and pain symptoms suffered by some, and risk of prolonged or permanent neurologic injury if the Service member incurs a second TBI before full recovery from the first. Concussions were seen more often during the recent conflicts in Afghanistan and Iraq than in prior conflicts, such as the Vietnam War, because of the use of improvised explosive devices that typically caused non-penetrating closed head injury. Since 2000 more than 300,000 Service members were diagnosed with TBI, of which more than 80 % were concussions. Improved TBI screening tools also have identified a higher than expected incidence of concussions occurring in garrison. In this review we summarize current epidemiologic data for TBI in the Military, and describe contemporary Military procedures and strategies for TBI prevention, identification, evaluation, and acute and chronic care. Key TBI clinical research priorities and programs are described, and innovative organizational plans to address future TBI needs are summarized.

Revisiting therapeutic hypothermia for severe traumatic brain injury... again.

Improved understanding of the molecular mechanisms of secondary brain injury has informed the optimum depth and duration of cooling and led to increased clinical interest in the therapeutic moderate hypothermia for severe traumatic brain injury over the past two decades. Although several large multi-center clinical trials have not found a treatment effect, multiple single-center trials have, and a recent meta-analysis by Crossley and colleagues now finds that the cumulative findings of those single-center trials dilute the multi-center trial results and show an overall reduction in mortality and poor outcomes associated with cooling. The need for consistent support of key physiologic parameters during cooling is emphasized by this finding.

Current recommendations for the diagnosis and treatment of concussion in sport: a comparison of three new guidelines.

Currently, there is considerable debate within the sports medicine community about the role of concussion and the risk of chronic neurological sequelae. This concern has led to significant confusion among primary care providers and athletic trainers about how to best identify those athletes at risk and how to treat those with concussion. During the first quarter of 2013, several new or updated clinical practice guidelines and position statements were published on the diagnosis, treatment, and management of mild traumatic brain injury/concussion in sports. Three of these guidelines were produced by the American Medical Society for Sports Medicine, The American Academy of Neurology, and the Zurich Consensus working group. The goal of each group was to clearly define current best practices for the definition, diagnosis, and acute and post-acute management of sports-related concussion, including specific recommendations for return to play. In this article, we compare the recommendations of each of the three groups, and highlight those topics for which there is consensus regarding the definition of concussion, diagnosis, and acute care of athletes suspected of having a concussion, as well as return-to-play recommendations.