Patterns of Anatomic Injury in Critically Injured Combat Casualties: A Network Analysis

Systemic inflammation induced from remote extremity trauma is a critical driver of secondary brain injury

Blast exposure, commonly experienced by military personnel, can cause devastating life-threatening polysystem trauma. Despite considerable research efforts, the impact of the systemic inflammatory response after major trauma on secondary brain injury-inflammation is largely unknown. The aim of this study was to identify markers underlying the susceptibility and early onset of neuroinflammation in three rat trauma models: (1) blast overpressure exposure (BOP), (2) complex extremity trauma (CET) involving femur fracture, crush injury, tourniquet-induced ischemia, and transfemoral amputation through the fracture site, and (3) BOP+CET. Six hours post-injury, intact brains were harvested and dissected to obtain biopsies from the prefrontal cortex, striatum, neocortex, hippocampus, amygdala, thalamus, hypothalamus, and cerebellum. Custom low-density microarray datasets were used to identify, interpret and visualize genes significant (p < 0.05 for differential expression [DEGs]; 86 neuroinflammation-associated) using a custom python-based computer program, principal component analysis, heatmaps and volcano plots. Gene set and pathway enrichment analyses of the DEGs was performed using R and STRING for protein-protein interaction (PPI) to identify and explore key genes and signaling networks. Transcript profiles were similar across all regions in naïve brains with similar expression levels involving neurotransmission and transcription functions and undetectable to low-levels of inflammation-related mediators. Trauma-induced neuroinflammation across all anatomical brain regions correlated with injury severity (BOP+CET > CET > BOP). The most pronounced differences in neuroinflammatory-neurodegenerative gene regulation were between blast-associated trauma (BOP, BOP+CET) and CET. Following BOP, there were few DEGs detected amongst all 8 brain regions, most were related to cytokines/chemokines and chemokine receptors, where PPI analysis revealed Il1b as a potential central hub gene. In contrast, CET led to a more excessive and diverse pro-neuroinflammatory reaction in which Il6 was identified as the central hub gene. Analysis of the of the BOP+CET dataset, revealed a more global heightened response (Cxcr2, Il1b, and Il6) as well as the expression of additional functional regulatory networks/hub genes (Ccl2, Ccl3, and Ccl4) which are known to play a critical role in the rapid recruitment and activation of immune cells via chemokine/cytokine signaling. These findings provide a foundation for discerning pathophysiological consequences of acute extremity injury and systemic inflammation following various forms of trauma in the brain.

A Review of 75th Ranger Regiment Battle-Injured Fatalities Incurred During Combat Operations From 2001 to 2021

INTRODUCTION

The 75th Ranger Regiment is an elite U.S. military special operations unit that conducted over 20 years of sustained combat operations. The Regiment has a history of providing novel and cutting-edge prehospital trauma care, advancing and translating medical initiatives, and documenting and reporting casualty care performance improvement efforts.

MATERIALS AND METHODS

A retrospective case fatality rate (CFR) review, mortality review, and descriptive analysis of fatalities were conducted for battle-injured personnel assigned or attached to the 75th Ranger Regiment from 2001 to 2021 during combat operations primarily in Afghanistan and Iraq. Fatalities were evaluated for population characteristics, cause of death, mechanism of death, injury severity, injury survivability, and death preventability.

RESULTS

A total of 813 battle injury casualties, including 62 fatalities, were incurred over 20 years and 1 month of continuous combat operations. The Regiment maintained a zero rate of prehospital preventable combat death. Additionally, no fatalities had a mechanism of death because of isolated extremity hemorrhage, tension pneumothorax, or airway obstruction. When comparing the CFR of the Regiment to the U.S. military population as a whole, the Regiment had a significantly greater reduction in the cumulative CFR as measured by the difference in average annual percentage change.

CONCLUSIONS

Documentation and analysis of casualties and care, mortality and casualty reviews, and other performance improvement efforts can guide combatant commanders, medical directors, and fighting forces to reduce preventable combat deaths and the CFR. Early hemorrhage control, blood product resuscitation, and other lifesaving interventions should be established and maintained as a standard prehospital practice to mitigate fatalities with potentially survivable injuries.

Firearm-Related Traumatic Brain Injury Homicides in the United States, 2000-2019

BACKGROUND

Traumatic brain injury (TBI) is a leading cause of homicide-related death in the United States. Penetrating TBI associated with firearms is a unique injury with an exceptionally high mortality rate that requires specialized neurocritical trauma care.

OBJECTIVE

To report incidence patterns of firearm-related and nonfirearm-related TBI homicides in the United States between 2000 and 2019 by demographic characteristics to provide foundational data for prevention and treatment strategies.

METHODS

Data were obtained from multiple cause of death records from the National Vital Statistics System using Centers for Disease Control and Prevention's Wide-Ranging Online Data for Epidemiologic Research database for the years 2000 to 2019. Number, age-adjusted rates, and percent of firearm and nonfirearm-related TBI homicides by demographic characteristics were calculated. Temporal trends were also evaluated.

RESULTS

During the study period, there were 77 602 firearm-related TBI homicides. Firearms were involved in the majority (68%) of all TBI homicides. Overall, men, people living in metro areas, and non-Hispanic Black persons had higher rates of firearm-related TBI homicides. The rate of nonfirearm-related TBI homicides declined by 40%, whereas the rate of firearm-related TBI homicides only declined by 3% during the study period. There was a notable increase in the rate of firearm-related TBI homicides from 2012/2013 through 2019 for women (20%) and nonmetro residents (39%).

CONCLUSION

Firearm-related violence is an important public health problem and is associated with the majority of TBI homicide deaths in the United States. The findings from this study may be used to inform prevention and guide further research to improve treatment strategies directed at reducing TBI homicides involving firearms.

Tourniquet-induced ischemia creates increased risk of organ dysfunction and mortality following delayed limb amputation

Tourniquets are critical for the control of traumatic extremity hemorrhage. In this study, we sought to determine, in a rodent blast-related extremity amputation model, the impact of prolonged tourniquet application and delayed limb amputation on survival, systemic inflammation, and remote end organ injury. Adult male Sprague Dawley rats were subjected to blast overpressure (120±7 kPa) and orthopedic extremity injury consisting femur fracture, one-minute soft tissue crush injury (20 psi), ± 180 min of tourniquet-induced hindlimb ischemia followed by delayed (60 min of reperfusion) hindlimb amputation (dHLA). All animals in the non-tourniquet group survived whereas 7/21 (33%) of the animals in the tourniquet group died within the first 72 h with no deaths observed between 72 and 168 h post-injury. Tourniquet induced ischemia-reperfusion injury (tIRI) likewise resulted in a more robust systemic inflammation (cytokines and chemokines) and concomitant remote pulmonary, renal, and hepatic dysfunction (BUN, CR, ALT. AST, IRI/inflammation-mediated genes). These results indicate prolonged tourniquet application and dHLA increases risk of complications from tIRI, leading to greater risk of local and systemic complications including organ dysfunction or death. We thus need enhanced strategies to mitigate the systemic effects of tIRI, particularly in the military prolonged field care (PFC) setting. Furthermore, future work is needed to extend the window within which tourniquet deflation to assess limb viability remains feasible, as well as new, limb-specific or systemic point of care tests to better assess the risks of tourniquet deflation with limb preservation in order to optimize patient care and save both limb and life.

Epidemiological characteristics and comparative outcome of blast versus gunshot injuries of the extremities in Somalia

BACKGROUND

War conflicts and terror-related injuries constitute a significant public health problem in Somalia. We aim to characterize and compare the injury characteristics of gunshot and blast injuries of the extremities.

METHODS

The data of 333 patients with gunshot and blast injuries of the extremities over three years were retrospectively reviewed. The demographics, injury characteristics, and outcomes were analyzed.

RESULTS

Most of the patients had injuries due to gunshot casualties compared with blast victims (n = 222, 66.7% vs. n = 111, 33.3%). Patients with gunshot wounds (GSW) had a more significant proportion of males than those with blast wounds (BW) (95.5% vs. 85.6%, P < 0.001). There were more open extremity fractures in GSW casualties (96.4% vs. 81.1%). The BW victims had significantly higher associated injuries (52.3% vs. 18.5%, P < 0.001). The BW group had a higher injury severity score (ISS ≥ 16 in 55%, P < 0.001). The need for an intensive care unit (ICU) admission was significantly higher in the BW patients (18% vs. 6.3%, P < 0.001); as well as the length of hospital stay (LOS) was higher in the BW group compared with the GW patients (> 2-week hospital stay in 31% vs. 19%, P < 0.04). About a 2.7% mortality rate was observed in BW (P < 0.014).

CONCLUSION

Gunshot and explosion injuries comprise the majority of war and terror-related trauma of the extremities. These injury mechanisms differ in the body regions involved, the severity of the injury, duration of hospital stay, need for ICU admission, and mortality. Assessment and management of such devastating casualties require a complex and multidisciplinary approach.

Wounding patterns in pediatric firearm fatalities

INTRODUCTION

Pediatric firearm injury became the leading cause of death among U.S. children in 2020. Studies evaluating wounding patterns in military and mass casualty shootings have provided insights into treatment and potential salvageability in adults, however, similar studies in the pediatric population do not exist. Hence, our study aimed to analyze wounding patterns of pediatric firearm fatalities and associated demographics and characteristics, such as place of death, to better understand pediatric firearm injuries, potential salvageability, and opportunities to reduce firearm deaths among vulnerable pediatric populations.

METHODS

A retrospective review of the National Violent Death Reporting System from 2005-2017 was performed on patients 18 and younger. Mortalities were stratified by patient age: <12 years and 13-18 years and by intent- homicide, suicide, and unintentional. Comparative and exploratory analyses of demographics, location of death and anatomic location of wounds were performed.

RESULTS

Of 8,527 pediatric firearm mortalities identified, 4,728 were homicides, 3,180 were suicides and 619 were unintentional injuries. Suicide victims were most likely to be dead on scene and >90% of suicide victims suffered head/neck injuries. For victims of homicide, younger children were more likely to die on scene (61% vs 44% p < 0.001). The pattern of injury in homicides differed for younger children compared to adolescents, with younger children with more head/neck injuries and older children more thoracic, thoracoabdominal, abdominal, and junctional injuries. In both age groups, children with extremity, abdominal and thoracoabdominal injuries were more likely to die later in the emergency department or inpatient setting.

CONCLUSIONS

Wounding patterns across pediatric firearm mortalities in the U.S. vary by age and intent. The majority of pediatric firearm deaths were due to head/neck injuries. Children with homicide and unintentional deaths had more wounding pattern variation, including more injuries to the thorax and abdomen, and a much lower rate of dead-on scene than suicide victims. Our study of wounding patterns among U.S. children killed by firearms highlights the complexity of these injuries and offers opportunities for tailored public health strategies across varying vulnerable pediatric populations.

Combat injury profiles among U.S. military personnel who survived serious wounds in Iraq and Afghanistan: A latent class analysis

Background

The U.S. military conflicts in Iraq and Afghanistan had the most casualties since Vietnam with more than 53,000 wounded in action. Novel injury mechanisms, such as improvised explosive devices, and higher rates of survivability compared with previous wars led to a new pattern of combat injuries. The purpose of the present study was to use latent class analysis (LCA) to identify combat injury profiles among U.S. military personnel who survived serious wounds.

Methods

A total of 5,227 combat casualty events with an Injury Severity Score (ISS) of 9 or greater that occurred in Iraq and Afghanistan from December 2002 to July 2019 were identified from the Expeditionary Medical Encounter Database for analysis. The Barell Injury Diagnosis Matrix was used to classify injuries into binary variables by site and type of injury. LCA was employed to identify injury profiles that accounted for co-occurring injuries. Injury profiles were described and compared by demographic, operational, and injury-specific variables.

Results

Seven injury profiles were identified and defined as: (1) open wounds (18.8%), (2) Type 1 traumatic brain injury (TBI)/facial injuries (14.2%), (3) disseminated injuries (6.8%), (4) Type 2 TBI (15.4%), (5) lower extremity injuries (19.8%), (6) burns (7.4%), and (7) chest and/or abdominal injuries (17.7%). Profiles differed by service branch, combat location, year of injury, injury mechanism, combat posture at the time of injury, and ISS.

Conclusion

LCA identified seven distinct and interpretable injury profiles among U.S. military personnel who survived serious combat injuries in Iraq or Afghanistan. These findings may be of interest to military medical planners as resource needs are evaluated and projected for future conflicts, and medical professionals involved in the rehabilitation of wounded service members.

Nanodelivery of oxiracetam enhances memory, functional recovery and induces neuroprotection following concussive head injury

Military personnel are the most susceptible to concussive head injury (CHI) caused by explosion, blast or missile or blunt head trauma. Mild to moderate CHI could induce lifetime functional and cognitive disturbances causing significant decrease in quality of life. Severe CHI leads to instant death and lifetime paralysis. Thus, further exploration of novel therapeutic agents or new features of known pharmacological agents are needed to enhance quality of life of CHI victims. Previous reports from our laboratory showed that mild CHI induced by weight drop technique causing an impact of 0.224N results in profound progressive functional deficit, memory impairment and brain pathology from 5h after trauma that continued over several weeks of injury. In this investigation we report that TiO2 nanowired delivery of oxiracetam (50mg/kg, i.p.) daily for 5 days after CHI resulted in significant improvement of functional deficit on the 8th day. This was observed using Rota Rod treadmill, memory improvement assessed by the time spent in finding hidden platform under water. The motor function improvement is seen in oxiracetam treated CHI group by placing forepaw on an inclined mesh walking and foot print analysis for stride length and distance between hind feet. TiO2-nanowired oxiracetam also induced marked improvements in the cerebral blood flow, reduction in the BBB breakdown and edema formation as well as neuroprotection of neuronal, glial and myelin damages caused by CHI at light and electron microscopy on the 7th day after 5 days TiO2 oxiracetam treatment. Adverse biochemical events such as upregulation of CSF nitrite and nitrate, IL-6, TNF-a and p-Tau are also reduced significantly in oxiracetam treated CHI group. On the other hand post treatment of 100mg/kg dose of normal oxiracetam in identical conditions after CHI is needed to show slight but significant neuroprotection together with mild recovery of memory function and functional deficits on the 8th day. These observations are the first to point out that nanowired delivery of oxiracetam has superior neuroprotective ability in CHI. These results indicate a promising clinical future of TiO2 oxiracetam in treating CHI patients for better quality of life and neurorehabilitation, not reported earlier.

Point-of-care ultrasound for treatment and triage in austere military environments

BACKGROUND

Assessment and triage in an austere environment represent a major challenge in casualty care. Modern conflicts involve a significant proportion of multiple wounds, either superficial or penetrating, which complicate clinical evaluation. Furthermore, there is often poor accessibility to computed tomography scans and a limited number of surgical teams. Therefore, ultrasound (US) represents a potentially valuable tool for distinguishing superficial fragments or shrapnels from penetrating trauma requiring immediate damage-control surgery.

METHODS

This retrospective observational multicenter study assessed casualties treated for 8 months by five medical teams deployed in Africa and Middle East. Two experts, who were experienced in military emergency medicine but did not take part in the missions, carried out an independent analysis for each case, evaluating the contribution of US to the following five items: triage categorization, diagnosis, clinical severity, prehospital therapeutic choices, and priority to operation room. Consensus was obtained using the Delphi method with three rounds.

RESULTS

Of 325 casualties, 189 underwent US examination. The mean injury severity scale score was 25.6, and 76% were wounded by an improvised explosive device. Ultrasound was useful for confirming (23%) or excluding (63%) the suspected diagnosis made in the clinical assessment. It also helped obtain a diagnosis that had not been considered for 3% of casualties and was responsible for a major change in procedure or therapy in 4%. Ultrasound altered the surgical priority in 43% of cases. For 30% of cases, US permitted surgery to be temporarily delayed to prioritize another more urgent casualty.

CONCLUSION

Ultrasound is a valuable tool for the management of mass casualties by improving treatment and triage, especially when surgical resources are limited. In some situations, US can also correct a diagnosis or improve prehospital therapeutic choices. Field medical teams should be trained to integrate US into their prehospital protocols.

LEVEL OF EVIDENCE

Case series (no criterion standard), level V.

United States military fatalities during Operation New Dawn

BACKGROUND

Military operations vary by scope, purpose, and intensity, each having unique forces and actions to execute a mission. Evaluation of military operation fatalities guides current and future casualty care.

METHODS

A retrospective study was conducted of all US military fatalities from Operation New Dawn in Iraq, 2010 to 2011. Data were obtained from autopsies and other records. Population characteristics, manner of death, cause of death, and location of death were analyzed. All fatalities were evaluated for concomitant evidence of underlying atherosclerosis. Nonsuicide trauma fatalities were also reviewed for injury severity, mechanism of death, injury survivability, death preventability, and opportunities for improvement.

RESULTS

Of 74 US military Operation New Dawn fatalities (median age, 26 years; male, 98.6%; conventional forces, 100%; prehospital, 82.4%) the leading cause of death was injury (86.5%). The manner of death was primarily homicide (55.4%), followed by suicide (17.6%), natural (13.5%), and accident (9.5%). Fatalities were divided near evenly between combatants (52.7%) and support personnel (47.3%), and between battle injury (51.4%) and disease and nonbattle injury (48.6%). Natural and suicide death was higher (p < 0.01, 0.02) among support personnel who were older (p = 0.05) with more reserve/national guard personnel (p = 0.01). Total population prevalence of underlying atherosclerosis was 18.9%, with more among support personnel (64.3%). Of 46 nonsuicide trauma fatalities, most died of blast injury (67.4%) followed by gunshot wound (26.1%) and multiple/blunt force injury (6.5%). The leading mechanism of death was catastrophic tissue destruction (82.6%). Most had nonsurvivable injuries (82.6%) and nonpreventable deaths (93.5%).

CONCLUSION

Operation New Dawn fatalities were exclusively conventional forces divided between combatants and support personnel, the former succumbing more to battle injury and the latter to disease and nonbattle injury including self-inflicted injury. For nonsuicide trauma fatalities, none died from a survivable injury, and 17.4% died from potentially survivable injuries. Opportunities for improvement included providing earlier blood products and surgery.

LEVEL OF EVIDENCE

Therapeutic, level V and epidemiological, level IV.

Vasopressors in Trauma: A Never Event?

Vasopressor use in severely injured trauma patients is discouraged due to concerns that vasoconstriction will worsen organ perfusion and result in increased mortality and organ failure in hypotensive trauma patients. Hypotensive resuscitation is advocated based on limited data that lower systolic blood pressure and mean arterial pressure will result in improved mortality. It is classically taught that hypotension and hypovolemia in trauma are associated with peripheral vasoconstriction. However, the pathophysiology of traumatic shock is complex and involves multiple neurohormonal interactions that are ultimately manifested by an initial sympathoexcitatory phase that attempts to compensate for acute blood loss and is characterized by vasoconstriction, tachycardia, and preserved mean arterial blood pressure. The subsequent hypotension observed in hemorrhagic shock reflects a sympathoinhibitory vasodilation phase. The objectives of hemodynamic resuscitation in hypotensive trauma patients are restoring adequate intravascular volume with a balanced ratio of blood products, correcting pathologic coagulopathy, and maintaining organ perfusion. Persistent hypotension and hypoperfusion are associated with worse coagulopathy and organ function. The practice of hypotensive resuscitation would appear counterintuitive to the goals of traumatic shock resuscitation and is not supported by consistent clinical data. In addition, excessive volume resuscitation is associated with adverse clinical outcomes. Therefore, in the resuscitation of traumatic shock, it is necessary to target an appropriate balance with intravascular volume and vascular tone. It would appear logical that vasopressors may be useful in traumatic shock resuscitation to counteract vasodilation in hemorrhage as well as other clinical conditions such as traumatic brain injury, spinal cord injury, multiple organ dysfunction syndrome, and vasodilation of general anesthetics. The purpose of this article is to discuss the controversy of vasopressors in hypotensive trauma patients and advocate for a nuanced approach to vasopressor administration in the resuscitation of traumatic shock.

Establishing an enduring Military Trauma Mortality Review: Misconceptions and lessons learned

Under direction from the Defense Health Agency, subject matter experts (SMEs) from the Joint Trauma System, Armed Forces Medical Examiner System, and civilian sector established the Military Trauma Mortality Review process. To establish the most empirically robust process, these SMEs used both qualitative and quantitative methods published in a series of peer-reviewed articles over the last 3 years. Most recently, the Military Mortality Review process was implemented for the first time on all battle-injured service members attached to the United States Special Operations Command from 2001 to 2018. The current Military Mortality Review process builds on the strengths and limitations of important previous work from both the military and civilian sector. To prospectively improve the trauma care system and drive preventable death to the lowest level possible, we present the main misconceptions and lessons learned from our 3-year effort to establish a reliable and sustainable Military Trauma Mortality Review process. These lessons include the following: (1) requirement to use standardized and appropriate lexicon, definitions, and criteria; (2) requirement to use a combination of objective injury scoring systems, forensic information, and thorough SME case review to make injury survivability and death preventability determinations; (3) requirement to use nonmedical information to make reliable death preventability determinations and a comprehensive list of opportunities for improvement to reduce preventable deaths within the trauma care system; and (4) acknowledgment that the military health system still has gaps in current infrastructure that must be addressed to globally and continuously implement the process outlined in the Military Trauma Mortality Review process in the future. LEVEL OF EVIDENCE: Level III.

Level 1 Trauma Centers and OEF/OIF Emergency Departments: Comparison of Trauma Patient Populations

INTRODUCTION

Brooke Army Medical Center (BAMC), the largest military hospital and the only level 1 trauma center in the DoD, cares for active duty, retired uniformed services personnel, and beneficiaries. In addition, BAMC works in collaboration with the Southwest Texas Regional Advisory Council (STRAC) and University Hospital (UH), San Antonio's other level 1 trauma center, to provide trauma care to residents of the city and 22 counties in southwest Texas from San Antonio to Mexico (26,000 square mile area). Civilian-military partnerships are shown to benefit the training of military medical personnel; however, to date, there are no published reports specific to military personnel experiences within emergency care. The purpose of the current study was to describe and compare the emergency department trauma patient populations of two level 1 trauma centers in one metropolitan city (BAMC and UH) as well as determine if DoD level 1 trauma cases were representative of patients treated in OEF/OIF emergency department settings.

MATERIALS AND METHODS

We obtained a nonhuman subjects research determination for de-identified data from the US Air Force 59th Medical Wing and the University of Texas Health Science Center at San Antonio Institutional Review Boards. Data on emergency department patients treated between the years 2015 and 2017 were obtained from the two level 1 trauma centers (BAMC and UH, located in San Antonio, Texas); data included injury descriptors, ICU and hospital days, and department procedures.

RESULTS

Two-proportion Z-tests indicated that trauma patients were similar across trauma centers on injury type, injury severity, and discharge status; yet trauma patients differed significantly in terms of mechanism of injury and regions of injury. BAMC received significantly greater proportions of patients injured from falls, firearms and with facial and head injuries than UH, which received significantly greater proportion of patients with thorax and abdominal injuries. In addition, a significantly greater proportion of patients spent more than 2 days in the ICU and greater than two total hospital days at BAMC than in UH. In comparison to military emergency departments in combat zones, BAMC had significantly lower rates of blood product administration and endotracheal intubations.

CONCLUSIONS

The trauma patients treated at a military level 1 trauma center were similar to those treated in the civilian level 1 trauma center in the same city, indicating the effectiveness of the only DoD Level 1 trauma center to provide experience comparable to that provided in civilian trauma centers. However, further research is needed to determine if the exposure rates to specific procedures are adequate to meet predeployment readiness requirements.

Mortality review of US Special Operations Command battle-injured fatalities

BACKGROUND

Comprehensive analyses of battle-injured fatalities, incorporating a multidisciplinary process with a standardized lexicon, is necessary to elucidate opportunities for improvement (OFIs) to increase survivability.

METHODS

A mortality review was conducted on United States Special Operations Command battle-injured fatalities who died from September 11, 2001, to September 10, 2018. Fatalities were analyzed by demographics, operational posture, mechanism of injury, cause of death, mechanism of death (MOD), classification of death, and injury severity. Injury survivability was determined by a subject matter expert panel and compared with injury patterns among Department of Defense Trauma Registry survivors. Death preventability and OFI were determined for fatalities with potentially survivable or survivable (PS-S) injuries using tactical data and documented medical interventions.

RESULTS

Of 369 United States Special Operations Command battle-injured fatalities (median age, 29 years; male, 98.6%), most were killed in action (89.4%) and more than half died from injuries sustained during mounted operations (52.3%). The cause of death was blast injury (45.0%), gunshot wound (39.8%), and multiple/blunt force injury (15.2%). The leading MOD was catastrophic tissue destruction (73.7%). Most fatalities sustained nonsurvivable injuries (74.3%). For fatalities with PS-S injuries, most had hemorrhage as a component of MOD (88.4%); however, the MOD was multifactorial in the majority of these fatalities (58.9%). Only 5.4% of all fatalities and 21.1% of fatalities with PS-S injuries had comparable injury patterns among survivors. Accounting for tactical situation, a minority of deaths were potentially preventable (5.7%) and a few preventable (1.1%). Time to surgery (93.7%) and prehospital blood transfusion (89.5%) were the leading OFI for PS-S fatalities. Most fatalities with PS-S injuries requiring blood (83.5%) also had an additional prehospital OFI.

CONCLUSION

Comprehensive mortality reviews of battlefield fatalities can identify OFI in combat casualty care and prevention. Standardized lexicon is essential for translation to civilian trauma systems.

LEVEL OF EVIDENCE

Epidemiological, level IV.

Evolution of hot zone care: MARA

Modern conflict and terrorist events have moved from linear two-dimensional battlespaces into complex, continuously evolving three-dimensional environments. Contested spaces make traditional definitions of zones of response confusing and lead to delays in care. The presence of actual or perceived ongoing threats creates an environment in which the initiation of tactical field care (TFC) may be inappropriate, despite the absence of an immediate risk to life. This risks a 'time and space gap' between care under fire and TFC. Major haemorrhage, airway, respiration, analgesia is proposed as a rethought approach to care in such environments.