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.

Quality of Life in United States Veterans With Combat-Related Ostomies From Iraq and Afghanistan

OBJECTIVE

Assess the impact of ostomy formation on quality of life for U.S. Service Members.

METHODS

U.S. personnel sustaining colorectal trauma from 2003 to 2011 were identified using the Department of Defense Trauma Registry. A cross-sectional observational study was conducted utilizing prospective interviews with standard survey instruments. Primary outcome measures were the Stoma Quality of Life Scale and Veterans RAND 36 scores and subjective responses. Patients with colorectal trauma not requiring ostomy served as controls.

RESULTS

Of 177 available patients, 90 (50.8%) male veterans consented to participate (55 ostomy, 35 control). No significant differences were observed between ostomy and control groups for Injury Severity Score (25.6 ± 9.9 vs. 22.9 ± 11.8, p = 0.26) or mechanism of injury (blast: 55 vs. 52%, p = 0.75); nonostomates had fewer anorectal injuries (3.2 vs. 47.9%, p < 0.01). Median follow-up was 6.7 years. Veterans RAND-36 Physical and Mental Component Scores were similar between groups. About 45.8% of ostomates were willing-to-trade a median of 10 years (interquartile range = 5-15) of their remaining life for gastrointestinal continuity. At last follow-up, 95.9% of respondents' combat-related ostomies were reversed with a median duration of 6 (range = 3-19) months diverted.

CONCLUSIONS

Ostomy creation in a combat environment remains safe and does not have a quantifiable impact on long-term quality of life.

U.S. Military Experience From 2001 to 2010 With Extremity Fasciotomy in War Surgery

INTRODUCTION

After trauma, compartment syndrome of the extremities is a common, disabling, and-if managed suboptimally-lethal problem. Its treatment by surgical fasciotomy continues to be useful but controversial. The purpose of this survey is to measure survival and fasciotomy in a large trauma system to characterize trends and to determine if fasciotomy is associated with improved survival.

METHODS

We retrospectively surveyed data from a military trauma registry for U.S. casualties from 2001 to 2010. Casualties had extremity injury or extremity fasciotomy. We associated survival and fasciotomy.

RESULTS

Of 17,166 casualties in the total study, 19% (3,313) had fasciotomy and 2.8% (481) had compartment syndrome. Annual fasciotomy rates started at 0% (2001) and rose to 26% (2010). For all casualties, the survival rate initially was high (100%) but decreased steadily until its nadir (96.4%) in 2005. Thereafter, it increased to make a V-shaped trend with reversal occurring after fielding two interventions within the trauma system specifically for casualties at risk for fasciotomy-tourniquet use and a fasciotomy education program.

CONCLUSIONS

Over a decade of war, the survival rate of extremity injured casualties was associated with two trauma system interventions-tourniquet usage and a fasciotomy education program. The current example of measuring implementation of initiatives may be useful as a model for future attempted improvements in health care.

A Modern Case Series of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) in an Out-of-Hospital, Combat Casualty Care Setting

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is used to mitigate bleeding and sustain central aortic pressure in the setting of shock. The ER-REBOA™ catheter is a new REBOA technology, previously reported only in the setting of civilian trauma and injury care. The use of REBOA in an out-of-hospital setting has not been reported, to our knowledge.

METHODS

We present a case series of wartime injured patients cared for by a US Air Force Special Operations Surgical Team at an austere location fewer than 3km (5-10 minutes' transport) from point of injury and 2 hours from the next highest environment of care-a Role 2 equivalent.

RESULTS

In a 2-month period, four patients presented with torso gunshot or fragmentation wounds, hemoperitoneum, and class IV shock. Hand-held ultrasound was used to diagnose hemoperitoneum and facilitate 7Fr femoral sheath access. ER-REBOA balloons were positioned and inflated in the aorta (zone 1 [n = 3] and zone 3 [n = 1]) without radiography. In all cases, REBOA resulted in immediate normalization of blood pressure and allowed induction of anesthesia, initiation of whole-blood transfusion, damage control laparotomy, and attainment of surgical hemostasis (range of inflation time, 18-65 minutes). There were no access- or REBOArelated complications and all patients survived to achieve transport to the next echelon of care in stable condition.

CONCLUSION

To our knowledge, this is the first series to demonstrate the feasibility and effectiveness of REBOA in modern combat casualty care and the first to describe use of the ER-REBOA catheter. Use of this device by nonsurgeons and surgeons not specially trained in vascular surgery in the out-of-hospital setting is useful as a stabilizing and damage control adjunct, allowing time for resuscitation, laparotomy, and surgical hemostasis.

The Role I Resuscitation Team and Resuscitative Endovascular Balloon Occlusion of the Aorta

The medical advancements made during the wars in Iraq and Afghanistan have resulted in an unprecedented survival rate, yet there is still a significant number of deaths that were potentially survivable. Additionally, the ability to deliver casualties to definitive surgical care within the "golden hour" is diminishing in many areas of conflict. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been implemented successfully in the hospital setting. REBOA may be a possible adjunct for the Role I and point-of-injury (POI) care to provide temporary control of noncompressible torso hemorrhage (NCTH) and junctional hemorrhage. Here the authors advocate for the development of the Role I Resuscitation Team (RT) and a training pathway to meet the challenge of the changing battlefield.

Combat related vascular injuries: Dutch experiences from a role 2 MTF in Afghanistan

BACKGROUND

In a combat environment, major vascular trauma endures as the leading cause of death. The Dutch role 2 Medical Treatment Facility (MTF), provided supportive care during the mission in Uruzgan, Afghanistan. Aim of this study was to conduct detailed analysis of the admitted major haemorrhages (vascular injuries) and to compare our findings with NATO coalition partners.

METHODS

Retrospective, descriptive study. Participants eligible for this study came from the role 2 MTF admission database, where they fitted the criteria 'Major haemorrhage (class 2 haemorrhage or more according to the ATLS(®) classification) between 2006 and 2010'. Results were contrasted with studies from coalition partners.

RESULTS

The query revealed 194 casualties sustaining 208 central (60% abdominal, 40% thoracic/neck), and 99 extremity major haemorrhages leading to 1.6 major haemorrhages per casualty. Survival was significantly better (p<0.05) in the peripheral vascular injuries cohort (96% versus 72%). Primary amputation was needed in 73/84 of lower, and in 8/15 of upper extremity major haemorrhages. Vascular repair or vascular Damage Control Surgery techniques (e.g. shunting) were used in 19/84 cases in the lower, and 7/15 in the upper extremity cohort, with a success rate of 69.2 percent. Amputation rates of coalition partners, using different inclusion and exclusion criteria, ranged from 5 to 60 percent.

CONCLUSIONS

Only in a few cases genuine peripheral vascular surgery was needed (<1%). This limited number of reconstructions does not demonstrate the need for extensive skills in all areas of vascular surgery. Achieved success rate until discharge was almost 70%. Vascular damage control surgery seems effective as initial limb saving skill in a role 2 MTF. The difference in usage of definitions concerning vascular injuries in current literature warrants further assessment. For optimal analysis there is need for detailed (NATO wide) registration with uniform definitions for vascular injuries.

LEVEL OF EVIDENCE

Level IV--Epidemiologic study.

Contributions of the surgeon Nikolai Korotkov (1874-1920) to the management of extremity vascular injury

The Russian military surgeon Nikolai Korotkov is known worldwide, mainly among internists and cardiovascular specialists, as the discoverer of the auscultatory method of measuring arterial blood pressure in 1905. This article reveals him as one of the first military vascular surgeons to carefully investigate, analyze, and register cases of vascular injury during his voluntarily trips to the Russian Far East in 1900 to 1901 and the Russo-Japanese War of 1904 to 1905. Examining 44 patients with extremity arterial and arterial-venous pseudoaneurysms following war-related injury, he routinely performed a measure termed the "arterial pressure index" using "Korotkov sounds." This pioneering approach to assessing extremity perfusion was the precursor to the modern-day ankle-brachial and injured extremity indices, and it initiated the quantitative assessment of the compensatory ability of the vascular system to restore circulation following axial artery ligation. Because of high thrombosis rates following direct vessel repair during his day, he proposed use of pharmacologic substances such as digitalis and amyl nitrite to improve extremity perfusion. As evidence of his innovative nature, Korotkov even proposed the use of "oxygenated nutrient solutions" in the future to improve extremity circulation. More than 100 years after his work, as continuous wave Doppler ultrasound, contrast angiography, and computed tomography are ubiquitous as diagnostic tools, the practice of surgery would be well served to recall Korotkov's foundational work and the rule of thumb for any physician: examine the patient.

Military-to-civilian translation of battlefield innovations in operative trauma care

BACKGROUND

Historic improvements in operative trauma care have been driven by war. It is unknown whether recent battlefield innovations stemming from conflicts in Iraq/Afghanistan will follow a similar trend. The objective of this study was to survey trauma medical directors (TMDs) at level 1-3 trauma centers across the United States and gauge the extent to which battlefield innovations have shaped civilian practice in 4 key domains of trauma care.

METHODS

Domains were determined by the use of a modified Delphi method based on multiple consultations with an expert physician/surgeon panel: (1) damage control resuscitation (DCR), (2) tourniquet use, (3) use of hemostatic agents, and (4) prehospital interventions, including intraosseous catheter access and needle thoracostomy. A corresponding 47-item electronic anonymous survey was developed/pilot tested before dissemination to all identifiable TMD at level 1-3 trauma centers across the US.

RESULTS

A total of 245 TMDs, representing nearly 40% of trauma centers in the United States, completed and returned the survey. More than half (n = 127; 51.8%) were verified by the American College of Surgeons. TMDs reported high civilian use of DCR: 95.1% of trauma centers had implemented massive transfusion protocols and the majority (67.7%) tended toward 1:1:1 packed red blood cell/fresh-frozen plasma/platelets ratios. For the other 3, mixed adoption corresponded to expressed concerns regarding the extent of concomitant civilian research to support military research and experience. In centers in which policies reflecting battlefield innovations were in use, previous military experience frequently was acknowledged.

CONCLUSION

This national survey of TMDs suggests that military data supporting DCR has altered civilian practice. Perceived relevance in other domains was less clear. Civilian academic efforts are needed to further research and enhance understandings that foster improved trauma surgeon awareness of military-to-civilian translation.