The epidemiology of blast lung injury during recent military conflicts: a retrospective database review of cases presenting to deployed military hospitals, 2003-2009

Identification of potentially functional circRNAs and prediction of the circRNA-miRNA-hub gene network in mice with primary blast lung injury

OBJECTIVES

Primary blast lung injury (PBLI) is the main cause of death in blast injury patients, and is often ignored due to the absence of a specific diagnosis. Circular RNAs (circRNAs) are becoming recognized as new regulators of various diseases, but the role of circRNAs in PBLI remain largely unknown. This study aimed to investigate PBLI-related circRNAs and their probable roles as new regulators in PBLI in order to provide new ideas for PBLI diagnosis and treatment.

METHODS

The differentially expressed (DE) circRNA and mRNA profiles were screened by transcriptome high-throughput sequencing and validated by quantitative real-time PCR (qRT-PCR). The GO and KEGG pathway enrichment was used to investigate the potential function of DE mRNAs. The interactions between proteins were analyzed using the STRING database and hub genes were identified using the MCODE plugin. Then, Cytoscape software was used to illustrate the circRNA-miRNA-hub gene network.

RESULTS

A total of 117 circRNAs and 681 mRNAs were aberrantly expressed in PBLI, including 64 up-regulated and 53 down-regulated circRNAs, and 315 up-regulated and 366 down-regulated mRNAs. GO and KEGG analysis revealed that the DE mRNAs might be involved in the TNF signaling pathway and Fanconi anemia pathway. Hub genes, including Cenpf, Ndc80, Cdk1, Aurkb, Ttk, Aspm, Ccnb1, Kif11, Bub1 and Top2a, were obtained using the MCODE plugin. The network consist of 6 circRNAs (chr18:21008725-21020999 + , chr4:44893533-44895989 + , chr4:56899026-56910247-, chr5:123709382-123719528-, chr9:108528589-108544977 + and chr15:93452117-93465245 +), 7 miRNAs (mmu-miR-3058-5p, mmu-miR-3063-5p, mmu-miR-668-5p, mmu-miR-7038-3p, mmu-miR-761, mmu-miR-7673-5p and mmu-miR-9-5p) and 6 mRNAs (Aspm, Aurkb, Bub1, Cdk1, Cenpf and Top2a).

CONCLUSIONS

This study examined a circRNA-miRNA-hub gene regulatory network associated with PBLI and explored the potential functions of circRNAs in the network for the first time. Six circRNAs in the circRNA-miRNA-hub gene regulatory network, including chr18:21008725-21020999 + , chr4:44893533-44895989 + , chr4:56899026-56910247-, chr5:123709382-123719528-, chr9:108528589-108544977 + and chr15:93452117-93465245 + may play an essential role in PBLI.

High risk and low prevalence diseases: Blast injuries

INTRODUCTION

Blast injury is a unique condition that carries a high rate of morbidity and mortality, often with mixed penetrating and blunt injuries.

OBJECTIVE

This review highlights the pearls and pitfalls of blast injuries, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION

Explosions may impact multiple organ systems through several mechanisms. Patients with suspected blast injury and multisystem trauma require a systematic evaluation and resuscitation, as well as investigation for injuries specific to blast injuries. Blast injuries most commonly affect air-filled organs but can also result in severe cardiac and brain injury. Understanding blast injury patterns and presentations is essential to avoid misdiagnosis and balance treatment of competing interests of patients with polytrauma. Management of blast victims can also be further complicated by burns, crush injury, resource limitation, and wound infection. Given the significant morbidity and mortality associated with blast injury, identification of various injury patterns and appropriate management are essential.

CONCLUSIONS

An understanding of blast injuries can assist emergency clinicians in diagnosing and managing this potentially deadly disease.

Blast Injury Patterns Among Israel Defense Forces Fatalities

INTRODUCTION

The incidence of blast injuries on the battlefield has risen over the last several decades. In order to improve prevention and treatment, it is essential to understand the severity and bodily distribution of these injuries. This study aims to characterize blast injury patterns among IDF fatalities.

MATERIALS AND METHODS

This is a descriptive, retrospective study on postmortem reports of military-blast fatalities between the years 1982 and 2021. Body regions injured according to the Abbreviated Injury Scale (AIS) were described. The frequency of body region injury combinations was mapped, and the correlation between injured body regions was calculated using Pearson's coefficient. Analysis of a subgroup with a postmortem computed tomography (CT-PM) or autopsy was performed, describing severe (AIS ≥ 3) injury patterns.

RESULTS

Overall, 222 fatalities suffered from blast injury, with most injuries affecting the upper and lower extremities (63.7% and 66.5%, respectively), followed by the head (57.1%) and the thorax (56.6%). The median number of injured body regions was 4 (interquartile range, 2-5). The most frequent injury combinations were the upper and lower extremities (51%), the upper extremities and the thorax (45%), and the lower extremities and the thorax (41%). In all, 47/222 (21.2%) fatalities had a documented autopsy or CT-PM report. Among the fatalities with CT-PM or autopsy, the head (63.8%) and the thorax (57.4%) were most frequently severely injured (AIS ≥ 3).

CONCLUSIONS

Among blast fatalities in the military setting, the extremities were most commonly injured. However, data suggest that the head and thorax are more likely to sustain severe blast injuries resulting in mortality. Blast injuries in this cohort were characterized by concomitant involvement of several regions. Development of protective gear to minimize the multisystem injuries inflicted by blast injuries is warranted and should be focused on distinct types and anatomical distribution of severe blast injuries as reported in this study.

LEVEL OF EVIDENCE

Level III, Retrospective analysis.

EFFECT OF EXOSOMES DERIVED FROM BONE MARROW MESENCHYMAL STEM CELLS ON PROGRAMMED CELL DEATH IN BLAST-INDUCED LUNG INJURY IN RATS

ABSTRACT

Blast lung injuries (BLIs) are frequent because of industrial accidents and terrorist groups. Bone marrow mesenchymal stem cells (BMSCs) and exosomes derived from BMSCs (BMSCs-Exo) have become a hot topic in modern biology because of their significance in damage healing, immune regulation, and gene therapy. The aim of this study is to investigate the effect of BMSCs and BMSCs-Exo on BLI in rats caused by gas explosion. Here, BMSCs and BMSCs-Exo were transplanted into BLI rats via tail vein and then evaluated pathological alterations, oxidative stress, apoptosis, autophagy, and pyroptosis in the lung tissue. Through histopathology and changes in malondialdehyde (MDA) and superoxide dismutase (SOD) contents, we discovered that oxidative stress and inflammatory infiltration in the lungs were significantly reduced by BMSCs and BMSCs-Exo. After treatment with BMSCs and BMSCs-Exo, apoptosis-related proteins, such as cleaved caspase-3 and Bax, were significantly decreased, and the ratio of Bcl-2/Bax was significantly increased; the level of pyroptosis-associated proteins, including NLRP3, GSDMD-N, cleaved caspase-1, IL-1β, and IL-18, were decreased; autophagy-related proteins, beclin-1 and LC3, were downregulated while P62 was upregulated; the number of autophagosomes was decreased. In summary, BMSCs and BMSCs-Exo attenuate BLI caused by gas explosion, which may be associated with apoptosis, aberrant autophagy, and pyroptosis.

REBOA for the Treatment of Blast Polytrauma: Zone 3 Provides Cerebral Perfusion, Attenuates Organ Dysfunction and Reperfusion Coagulopathy Compared to Zone 1 in a Swine Model

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a lifesaving therapy for hemorrhagic shock following pelvic/lower extremity injuries in military settings. However, Zone 1 aortic occlusion (AO; above the celiac artery), while providing brain/cardiac perfusion, may induce/worsen visceral ischemia and organ dysfunction. In contrast, AO Zone 3 (below the renal arteries) provides abdominal perfusion potentially minimizing ischemia/reperfusion injury. We hypothesized that, compared with AO Zone 1, AO Zone 3 provides neuro/cardioprotection while minimizing visceral ischemia and reperfusion coagulopathy after severe traumatic hemorrhage due to pelvic/lower extremity injuries.

METHODS

Fifty-kilogram male Yorkshire swine underwent a blast polytrauma injury followed by a resuscitation protocol with randomization to no AO (No AO, n = 6) or AO with REBOA at Zone 1 (AO Zone 1; n = 6) or Zone 3 (AO Zone 3; n = 4). Vital signs and intracranial pressure (ICP) were monitored for 240 minutes. Citrate native and tissue plasminogen activator challenge thrombelastography, prothrombin time, creatinine, lipase, total bilirubin, troponin, and enzyme-linked immunosorbent assays protein levels were measured at set intervals.

RESULTS

Both AO groups had significant increases in mean arterial pressure during aortic occlusion. All three groups had significant increases in ICP, but final ICP in the No AO group (26 ± 5.8 mm Hg) was significantly elevated compared with AO Zone 1 (17 ± 5.2 mm Hg) and AO Zone 3 (16 ± 4.2 mm Hg) ( p < 0.01). The final mean troponin in the No AO group (4.10 ± 5.67 ng/mL) was significantly higher than baseline (0.03 ± 0.02 ng/mL, p < 0.05), while the two AO groups had no significant changes ( p > 0.05). AO Zone 1 was the only group associated with hyperfibrinolysis ( p < 0.05) and significantly increased prothrombin time ( p < 0.05). Only AO Zone 1 group had significantly higher markers of organ damage.

CONCLUSION

Compared with AO Zone 1, AO Zone 3 provided similar neuro/cardioprotection but with less organ dysfunction and coagulopathy. This study suggests that Zone 3 REBOA may be preferable over Zone 1 for treating military relevant blast polytrauma with minimal intra-abdominal and chest trauma, but further clinical investigation is warranted.

Understanding the burden of injury in children from conflict: an analysis of radiological imaging from a Role 3 hospital in Afghanistan in 2011

INTRODUCTION

There is a need for quality medical care for children injured in conflict, but a description of injuries and injury burden from blast and ballistic mechanisms is lacking. The radiology records of children imaged during the war in Afghanistan represent a valuable source of information about the patterns of paediatric conflict injuries.

METHODS

The UK military radiological database was searched for all paediatric presentations to Camp Bastion during 2011. Reports and original images were reviewed to determine location and severity of injuries sustained. Additional information was obtained from imaging request forms and the Joint Theatre Trauma Register, a database of those treated at UK medical facilities in Iraq and Afghanistan.

RESULTS

Radiology was available for 219 children. 71% underwent CT scanning. 46% suffered blast injury, 22% gunshot wounds (GSWs), and 32% disease and non-battle injuries (DNBIs). 3% had penetrating head injury, 11% penetrating abdominal trauma and 8% lower limb amputation, rates far exceeding those found in civilian practice. Compared with those with DNBI, those with blast or GSW were more likely to have serious (Abbreviated Injury Score, AIS, ≥3) injuries (median no. AIS ≥3 injuries were 1 for blast, 1 for GSW and 0 for DNBI, p<0.05) and children exposed to blast were more likely to have multiple body regions with serious injuries (OR for multiple AIS ≥3 injuries for blast vs DNBI=5.811 CI [1.877 to 17.993], p<0.05).

CONCLUSIONS

Paediatric conflict injuries are severe, and clinicians used only to civilian practice may be unprepared for the nature and severity of injuries inflicted on children in conflict. Whole-body CT for those with conflict-related injuries, especially blast, is hugely valuable. We recommend that CT is used for paediatric assessment in blast and ballistic incidents and that national imaging guidelines amend the threshold for doing so.

[The role of the pulmonologist in an armed conflict]

INTRODUCTION

Recent news points to the eventuality of an armed conflict on the national territory.

STATE OF THE ART

In this situation, pulmonologists will in all likelihood have a major role to assume in caring for the injured, especially insofar as chest damage is a major cause of patient death.

PERSPECTIVES

The main injuries that pulmonologists may be called upon to treat stem not only from explosions, but also from chemical, biological and nuclear hazards. In this article, relevant organizational and pedagogical aspects are addressed. Since exhaustiveness on this subject is unattainable, we are proposing training on specific subjects for interested practitioners.

CONCLUSION

The resilience of the French health system in a situation of armed conflict depends on the active participation of all concerned parties. With this in mind, it is of prime importance that the pneumological community be sensitized to the potential predictable severity of war-related injuries.

A novel animal model of primary blast lung injury and its pathological changes in mice

BACKGROUND

Primary blast lung injury (PBLI) is a major cause of death in military conflict and terrorist attacks on civilian populations. However, the mechanisms of PBLI are not well understood, and a standardized animal model is urgently needed. This study aimed to establish an animal model of PBLI for laboratory study.

METHODS

The animal model of PBLI was established using a self-made mini shock tube simulation device. In brief, mice were randomly divided into two groups: the control group and the model group, the model group were suffered 0.5 bar shock pressures. Mice were sacrificed at 2 hours, 4 hours, 6 hours, 12 hours, and 24 hours after injury. Lung tissue gross observation, hematoxylin and eosin staining and lung pathology scoring were performed to evaluated lung tissue damage. Evans blue dye leakage and bronchoalveolar lavage fluid examination were performed to evaluated pulmonary edema. The relative expression levels of inflammation factors were measured by real-time quantitative polymerase chain reaction and Western blotting analysis. The release of neutrophil extracellular traps was observed by immunofluorescence stain.

RESULTS

In the model group, the gross observation and hematoxylin and eosin staining assay showed the inflammatory cell infiltration, intra-alveolar hemorrhage, and damaged lung tissue structure. The Evans blue dye and bronchoalveolar lavage fluid examination revealed that the lung tissue permeability and edema was significantly increased after injury. Real-time quantitative polymerase chain reaction and Western blotting assays showed that IL-1β, IL-6, TNF-α were upregulated in the model group. Immunofluorescence assay showed that the level of neutrophil extracellular traps in the lung tissue increased significantly in the model group.

CONCLUSION

The self-made mini shock tube simulation device can be used to establish the animal model of PBLI successfully. Pathological changes of PBLI mice were characterized by mechanical damage and inflammatory response in lung tissue.

Imaging findings in patients after the bomb explosion in Somalia on December 28, 2019

INTRODUCTION

This study aimed to present the radiological findings of injuries in victims as a result of a suicide bombing in Mogadishu, Somalia.

METHODS

Of the 82 injured cases admitted to the emergency department within the first six hours after the explosion, those who were radiologically evaluated were included in this retrospective and descriptive study. To analyze and identify the distribution of primary, secondary, and tertiary injuries, they were classified according to the body areas as head-neck, thorax, abdominopelvic, extremity, and vertebra.

RESULTS

The mean age (mean ± SD) of 63 patients included in the study was 28.6 ± 10.2 years. Twenty-four (38.1%) of the injured patients were female and 39 (61.9%) were male. Secondary blast injury was the most common type of injury in the study group with a rate of 39/63 (62%). The total number of bomb fragments was 235, of which 113 (47.8%) were seen in the head and neck region, followed by 86 (36.5%) in the extremities. There were 10 patients (15.9%) with lung injury and 13 (20.6%) with tympanic membrane perforation due to the primary blast mechanism.

CONCLUSION

Radiological imaging plays an important role in identifying specific findings and patterns of explosive injuries. Therefore, we consider that patients with stable hemodynamics should be radiologically examined for a fast and accurate diagnosis or treatment.

Proteomic Analysis Revealed the Characteristics of Key Proteins Involved in the Regulation of Inflammatory Response, Leukocyte Transendothelial Migration, Phagocytosis, and Immune Process during Early Lung Blast Injury

Previous studies found that blast injury caused a significant increased expression of interleukin-1, IL-6, and tumor necrosis factor, a significant decrease in the expression of IL-10, an increase in Evans blue leakage, and a significant increase in inflammatory cell infiltration in the lungs. However, the molecular characteristics of lung injury at different time points after blast exposure have not yet been reported. Therefore, in this study, tandem mass spectrometry (TMT) quantitative proteomics and bioinformatics analysis were used for the first time to gain a deeper understanding of the molecular mechanism of lung blast injury at different time points. Forty-eight male C57BL/6 mice were randomly divided into six groups: control, 12 h, 24 h, 48 h, 72 h, and 1 w after low-intensity blast exposure. TMT quantitative proteomics and bioinformatics analysis were performed to analyze protein expression profiling in the lungs from control and blast-exposed mice, and differential protein expression was verified by Western blotting. The results demonstrated that blast exposure induced severe lung injury, leukocyte infiltration, and the production of inflammatory factors in mice. After analyzing the expression changes in global proteins and inflammation-related proteomes after blast exposure, the results showed that a total of 6861 global proteins and 608 differentially expressed proteins were identified, of which 215, 128, 187, 232, and 65 proteins were identified at 12 h, 24 h, 48 h, 72 h, and 1 week after blast exposure, respectively. Moreover, blast exposure-induced 177 differentially expressed proteins were associated with inflammatory responses, which were enriched in the inflammatory response regulation, leukocyte transendothelial migration, phagocytosis, and immune response. Therefore, blast exposure may induce early inflammatory response of lung tissue by regulating the expression of key proteins in the inflammatory process, suggesting that early inflammatory response may be the initiating factor of lung blast injury. These data can provide potential therapeutic candidates or approaches for the development of future treatment of lung blast injury.

NF-κB and FosB mediate inflammation and oxidative stress in the blast lung injury of rats exposed to shock waves

Blast lung injury (BLI) is the major cause of death in explosion-derived shock waves; however, the mechanisms of BLI are not well understood. To identify the time-dependent manner of BLI, a model of lung injury of rats induced by shock waves was established by a fuel air explosive. The model was evaluated by hematoxylin and eosin staining and pathological score. The inflammation and oxidative stress of lung injury were also investigated. The pathological scores of rats' lung injury at 2 h, 24 h, 3 days, and 7 days post-blast were 9.75±2.96, 13.00±1.85, 8.50±1.51, and 4.00±1.41, respectively, which were significantly increased compared with those in the control group (1.13±0.64; P<0.05). The respiratory frequency and pause were increased significantly, while minute expiratory volume, inspiratory time, and inspiratory peak flow rate were decreased in a time-dependent manner at 2 and 24 h post-blast compared with those in the control group. In addition, the expressions of inflammatory factors such as interleukin (IL)-6, IL-8, FosB, and NF-κB were increased significantly at 2 h and peaked at 24 h, which gradually decreased after 3 days and returned to normal in 2 weeks. The levels of total antioxidant capacity, total superoxide dismutase, and glutathione peroxidase were significantly decreased 24 h after the shock wave blast. Conversely, the malondialdehyde level reached the peak at 24 h. These results indicated that inflammatory and oxidative stress induced by shock waves changed significantly in a time-dependent manner, which may be the important factors and novel therapeutic targets for the treatment of BLI.

Pulmonary injury risk curves and behavioral changes from blast overpressure exposures of varying frequency and intensity in rats

At present, there are no set guidelines establishing cumulative limits for blast exposure numbers and intensities in military personnel, in combat or training operations. The objective of the current study was to define lung injury, pathology, and associated behavioral changes from primary repeated blast lung injury under appropriate exposure conditions and combinations (i.e. blast overpressure (BOP) intensity and exposure frequency) using an advanced blast simulator. Male Sprague Dawley rats were exposed to BOP frontally and laterally at a pressure range of ~ 8.5-19 psi, for up to 30 daily exposures. The extent of lung injury was identified at 24 h following BOP by assessing the extent of surface hemorrhage/contusion, Hematoxylin and Eosin staining, and behavioral deficits with open field activity. Lung injury was mathematically modeled to define the military standard 1% lung injury threshold. Significant levels of histiocytosis and inflammation were observed in pressures ≥ 10 psi and orientation effects were observed at pressures ≥ 13 psi. Experimental data demonstrated ~ 8.5 psi is the threshold for hemorrhage/contusion, up to 30 exposures. Modeling the data predicted injury risk up to 50 exposures with intensity thresholds at 8 psi for front exposure and 6psi for side exposures, which needs to be validated further.

Management of orthopaedic injuries in Libyan civil war: experiences of a distant hospital

AIM OF THE STUDY

In this study, we aimed to evaluate the musculoskeletal injury types, infections, and treatments of the patients injured in Libyan civil war.

METHODS

A total of 291 patients (288 male, 3 female) treated in our clinic, between November 2011 and April 2020, were included in our retrospective study. Patients' age, injury severity score (ISS), injury type, mechanism, location, accompanying traumas, infection, and operations in Libya and in our clinic were evaluated.

RESULTS

Injuries were caused by gunshots in 172 patients, by explosives in 56, by missiles in eight, and by different mechanisms in the remaining 55 patients. Injuries were located mostly in lower extremities, followed by upper extremities and by both extremities. The most common fracture was tibial fractures, followed with femur and humerus. Plate-screw fixation was performed for 82 cases, intramedullary nailing for 42, external fixator for 41, K-wire fixation for 27, foreign body excisions for 26, arthrodesis for 15, amputation for , arthroplasty for 11, and soft tissue operations for 78. Infection was present among 50 (% 17.2) patients. Complications were seen in five patients. Three patients needed implant removal due to infection, one patient had a plate fracture, and one patient died because of sepsis.

DISCUSSION

Difficulties in the treatment of war injuries begin in the battlefield. Patients' transfers and treatments may not be provided properly due to unsuitable conditions. Hospitals in neighbouring and distant countries can be helpful for supporting the treatment of increased numbers of injured patients.

CONCLUSION

Wars cause excessive numbers of injuries. In this study, we want to show that hospitals far from war zones can be considered as alternatives for treatment of these injuries.

Anthropomorphic Blast Test Device for Primary Blast Injury Risk Assessment

INTRODUCTION

Blast overpressure health hazard assessment is required prior to fielding of weapon systems that produce blast overpressures that pose risk of auditory and nonauditory blast lung injuries. The anthropomorphic blast test device (ABTD) offers a single device solution for collection of both auditory and nonauditory data from a single blast at anthropometrically correct locations for injury risk assessment. It also allows for better replication of personnel positioning during weapons firings. The ABTD is an update of the blast test device (BTD), the current Army standard for collection of thoracic blast loading data. Validation testing of the ABTD is required to ensure that lung injury model validated using BTD collected test data and sheep subjects is still applicable when the ABTD is used.

METHODS

Open field validation blast tests were conducted with BTD and ABTD placed at matching locations. Tests at seven blast strength levels were completed spanning the range of overpressures for occupational testing.

RESULTS

The two devices produced very similar values for lung injury dose over all blast levels and orientations.

CONCLUSION

The ABTD was validated successfully for open field tests. For occupational blast injury assessments, ABTD can be used in place of the BTD and provide enhanced capabilities.

Management of combined massive burn and blast injury: A 20-year experience

INTRODUCTION

Blast injuries are complex types of physical trauma resulting from direct or indirect exposure to an explosion, which can be divided into four classes: primary, secondary, tertiary, and quaternary. Primary blast injury results in damage, principally, in gas-containing organs such as the lungs (blast lung injury, BLI). BLI is defined as radiological and clinical evidence of acute lung injury occurring within 12h of exposure to an explosion and not due to secondary or tertiary injury. BLI often combines with cutaneous thermal injury, a type of quaternary blast injury, either in terrorist bomb attacks or in civilian accidental explosions. This report summarizes our experience in the management of combined massive burn and BLI at a Shanghai Burn Center in China.

METHODS

A retrospective observational analysis of clinical data was performed for massive burn patients with or without BLI during a 20-year interval. Patient characteristics, causes of injury, clinical parameters, management, and outcomes were recorded and evaluated.

RESULTS

A total of 151 patients (120 males and 31 females) with severe burn injury (≥50% TBSA) treated at the Burn Center of Changhai Hospital in Shanghai between July 1997 and June 2017 were enrolled in this study. Their mean age was 38.6±17.8 (3-75) years. Among them, 28 patients had combined BLI and burn injury and 39 patients had no BLI or smoke inhalation injury (non-BLI-SII). No significant difference was observed in the burn area or full-thickness burn area between the two groups. The lowest PaO₂/fraction of inspired oxygen (FiO₂) ratio during the first 24h in BLI patients was significantly lower than that in non-BLI-SII patients. Exudative changes were observed by X-ray radiography in all BLI patients but not in non-BLI-SII patients within 6h after injury. A significantly higher proportion of colloids were used for fluid resuscitation in BLI patients than that in non-BLI-SII patients. A higher proportion and longer time of mechanical ventilation were needed for BLI patients than those for non-BLI-SII patients, and a higher proportion of patients received sedative agents in the BLI group than those in the non-BLI-SII group. The first escharectomy was performed relatively later in BLI patients than in non-BLI-SII patients because of more time taken by BLI patients to recover from lung injury. The length of ICU and hospital stay in BLI patients was significantly longer than that in non-BLI-SII patients. No significant difference in the overall mortality was detected between these two groups.

CONCLUSION

It is a formidable challenge for clinicians to diagnose and manage massive burn patients combined with BLI. A comprehensive treatment approach is strongly recommended, including fluid resuscitation, airway management, mechanical ventilation, and surgical treatment. Given the high mortality of massive burn patients combined with BLI even in a recognized burn center, more prospective studies are encouraged to assess more effective strategies for the treatment of such patients.

Blast-Induced Cholesteatomas After Spontaneous Tympanic Membrane Healing

OBJECTIVES

To characterize blast-induced cholesteatomas (BIC) in terms of symptoms, presentation, and location within the middle ear cleft (MEC).

DESIGN

A search for all English language articles in "MEDLINE" via "PubMed" and "Google Scholar" was conducted.

RESULTS

A total of 67 ears with BIC were included. Fifty-eight ears in which the traumatic perforation failed to spontaneously close were excluded, leaving seven case reports (eight patients, nine ears) for statistical analysis. Time between blast exposure to spontaneous tympanic membrane (TM) closure was 16 days to 10 months. Time between blast exposure and cholesteatoma diagnosis was 5 months to 4 years. The cholesteatomas were diagnosed due to symptoms in two ears, as asymptomatic finding on physical examination in one ear and as asymptomatic finding in axial imaging in three ears.

CONCLUSIONS

BICs can develop behind intact tympanic membrane or along with TM perforation. Based on the current review, when a TM perforation and spontaneous healing were documented, after blast exposure, MRI scan is an integral component of the follow-up. The optimal timing for MRI performance after blast exposure, is yet to be identified.

Computational Modeling of Primary Blast Lung Injury: Implications for Ventilator Management

Primary blast lung injury (PBLI) caused by exposure to high-intensity pressure waves is associated with parenchymal tissue injury and severe ventilation-perfusion mismatch. Although supportive ventilation is often required in patients with PBLI, maldistribution of gas flow in mechanically heterogeneous lungs may lead to further injury due to increased parenchymal strain and strain rate, which are difficult to predict in vivo. In this study, we developed a computational lung model with mechanical properties consistent with healthy and PBLI conditions. PBLI conditions were simulated with bilateral derecruitment and increased perihilar tissue stiffness. As a result of these tissue abnormalities, airway flow was heterogeneously distributed in the model under PBLI conditions, during both conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation. PBLI conditions resulted in over three-fold higher parenchymal strains compared to the healthy condition during CMV, with flow distributed according to regional tissue stiffness. During high-frequency oscillatory ventilation, flow distribution became increasingly heterogeneous and frequency-dependent. We conclude that the distribution and rate of parenchymal distension during mechanical ventilation depend on PBLI severity as well as ventilatory modality. These simulations may allow realistic assessment of the risks associated with ventilator-induced lung injury following PBLI, and facilitate the development of alternative lung-protective ventilation modalities.

Nebulised recombinant activated factor VII (rFVIIa) does not attenuate the haemorrhagic effects of blast lung injury

Introduction

Primary blast lung injury causes intrapulmonary haemorrhage. A number of case reports have suggested the efficacy of recombinant activated factor VII (rFVIIa) in the treatment of diffuse alveolar haemorrhage from a range of medical causes, but its efficacy in blast lung is unknown. The aim of this study was to investigate whether nebulised rFVIIa attenuates the haemorrhagic effects of blast lung injury in an animal model.

Methods

Terminally anaesthetised rabbits subjected to blast lung injury were randomised to receive either rFVIIa or placebo via a nebuliser. The primary outcome was the level of blood iron–transferrin complex, a marker of the extent of blast lung injury, analysed using low temperature electron paramagnetic resonance spectroscopy.

Results

Blast exposure led to a significant fall in iron-bound transferrin in both groups of animals (p<0.001), which remained depressed during the study. There were no significant differences in iron–transferrin between the rFVIIa and placebo treatment groups over the duration of the study (p=0.081), and there was no trend towards elevated iron–transferrin in the rFVIIa-treated group once drug treatment had started. There was suggestive evidence of systemic absorption of rFVIIa given via the inhaled route.

Conclusion

A single dose of nebulised rFVIIa did not attenuate pulmonary haemorrhage in a rabbit model of blast lung injury. As there was some evidence of systemic absorption, the inhaled route does not avoid the concern about potential thromboembolic complications from administration of rFVIIa.

Caffeine attenuates brain injury but increases mortality induced by high-intensity blast wave exposure

Caffeine is a substance that is consumed worldwide, and it may exert neuroprotective effects against various cerebral insults, including neurotrauma, which is the most prevalent injury among military personnel. To investigate the effects of caffeine on high-intensity blast wave-induced severe blast injury in mice, three different paradigms of caffeine were applied to male C57BL/6 mice with severe whole body blast injury (WBBI). The results demonstrated that chronic caffeine treatment alleviated blast-induced traumatic brain injury (bTBI); however, both chronic and acute caffeine treatments exacerbated blast-induced lung injuries and, more importantly, increased both the cumulative and time-segmented mortalities postinjury. Interestingly, withdrawing caffeine intake preinjury resulted in favorable outcomes in mortality and lung injury, similar to the findings in water-treated mice, and had the trend to attenuate brain injury. These findings demonstrated that although drinking coffee or caffeine preparations attenuated blast-induced brain trauma, these beverages may place personnel in the battlefield at high risk of casualties, which will help us re-evaluate the therapeutic strategy of caffeine application, particularly in multiple-organ-trauma settings. Furthermore, these findings provided possible strategies for reducing the risk of casualties with caffeine consumption, which may help to change the coffee-drinking habits of military personnel.

Blast-induced brain injury in rats leads to transient vestibulomotor deficits and persistent orofacial pain

Blast-induced traumatic brain injury (blast-TBI) is associated with vestibulomotor dysfunction, persistent post-traumatic headaches and post-traumatic stress disorder, requiring extensive treatments and reducing quality-of-life. Treatment and prevention of these devastating outcomes require an understanding of their underlying pathophysiology through studies that take advantage of animal models. Here, we report that cranium-directed blast-TBI in rats results in signs of pain that last at least 8 weeks after injury. These occur without significantly elevated behavioural markers of anxiety-like conditions and are not associated with glial up-regulation in sensory thalamic nuclei. These injuries also produce transient vestibulomotor abnormalities that resolve within 3 weeks of injury. Thus, blast-TBI in rats recapitulates aspects of the human condition.

Chinese expert consensus on echelons treatment of thoracic injury in modern warfare

The emergency treatment of thoracic injuries varies of general conditions and modern warfare. However, there are no unified battlefield treatment guidelines for thoracic injuries in the Chinese People's Liberation Army (PLA). An expert consensus has been reached based on the epidemiology of thoracic injuries and the concept of battlefield treatment combined with the existing levels of military medical care in modern warfare. Since there are no differences in the specialized treatment for thoracic injuries between general conditions and modern warfare, first aid, emergency treatment, and early treatment of thoracic injuries are introduced separately in three levels in this consensus. At Level I facilities, tension pneumothorax and open pneumothorax are recommended for initial assessment during the first aid stage. Re-evaluation and further treatment for hemothorax, flail chest, and pericardial tamponade are recommended at Level II facilities. At Level III facilities, simple surgical operations such as emergency thoracotomy and debridement surgery for open pneumothorax are recommended. The grading standard for evidence evaluation and recommendation was used to reach this expert consensus.

A comparison of CT lung voxel density analysis in a blast and non blast injured casualty

INTRODUCTION

Primary blast lung injury (PBLI) is a prominent feature in casualties following exposure to blast. PBLI carries high morbidity and mortality, but remains difficult to diagnose and quantify. Radiographic diagnosis of PBLI was historically made with the aid of plain radiographs; more recently, qualitative review of CT images has assisted diagnosis.

METHODS

We report a novel way of measuring post-traumatic acute lung injury using CT lung density analysis in two casualties. One casualty presented following blast exposure with confirmed blast lung injury and the other presented following extremity injury without blast exposure. Three-dimensional lung maps of each casualty were produced from their original trauma CT scan. Analysis of the lung maps allowed quantitative radiological comparison exposing areas of reduced aeration of the patient's lungs.

RESULTS

45% of the blast-exposed lungs were non-aerated compared with 10% in the non-blast-exposed lungs.

DISCUSSION

In these example cases quantitative CT lung density analysis allowed blast-injured lungs to be distinguished from non-blast-exposed lungs.

Hemostatic nanoparticles increase survival, mitigate neuropathology and alleviate anxiety in a rodent blast trauma model

Explosions account for 79% of combat related injuries and often lead to polytrauma, a majority of which include blast-induced traumatic brain injuries (bTBI). These injuries lead to internal bleeding in multiple organs and, in the case of bTBI, long term neurological deficits. Currently, there are no treatments for internal bleeding beyond fluid resuscitation and surgery. There is also a dearth of treatments for TBI. We have developed a novel approach using hemostatic nanoparticles that encapsulate an anti-inflammatory, dexamethasone, to stop the bleeding and reduce inflammation after injury. We hypothesize that this will improve not only survival but long term functional outcomes after blast polytrauma. Poly(lactic-co-glycolic acid) hemostatic nanoparticles encapsulating dexamethasone (hDNPs) were fabricated and tested following injury along with appropriate controls. Rats were exposed to a single blast wave using an Advanced Blast Simulator, inducing primary blast lung and bTBI. Survival was elevated in the hDNPs group compared to controls. Elevated anxiety parameters were found in the controls, compared to hDNPs. Histological analysis indicated that apoptosis and blood-brain barrier disruption in the amygdala were significantly increased in the controls compared to the hDNPs and sham groups. Immediate intervention is crucial to mitigate injury mechanisms that contribute to emotional deficits.

Primary Blast Brain Injury Mechanisms: Current Knowledge, Limitations, and Future Directions

Mild blast traumatic brain injury (bTBI) accounts for the majority of brain injury in United States service members and other military personnel worldwide. The mechanisms of primary blast brain injury continue to be disputed with little evidence to support one or a combination of theories. The main hypotheses addressed in this review are blast wave transmission through the skull orifices, direct cranial transmission, skull flexure dynamics, thoracic surge, acceleration, and cavitation. Each possible mechanism is discussed using available literature with the goal of focusing research efforts to address the limitations and challenges that exist in blast injury research. Multiple mechanisms may contribute to the pathology of bTBI and could be dependent on magnitudes and orientation to blast exposure. Further focused biomechanical investigation with cadaver, in vivo, and finite element models would advance our knowledge of bTBI mechanisms. In addition, this understanding could guide future research and contribute to the greater goal of developing relevant injury criteria and mandates to protect our soldiers on the battlefield.

Understanding blast-induced neurotrauma: how far have we come?

Blast injuries, including blast-induced neurotrauma (BINT), are caused by blast waves generated during an explosion. Accordingly, their history coincides with that of explosives. Hence, it is intriguing that, after more than 1000 years of using explosives, our understanding of the pathological consequences of blast and body/brain interactions is extremely limited. Postconflict recovery mechanisms seemingly include the suppression of painful experiences, such as explosive injuries. Unfortunately, ignoring the knowledge generated by previous generations of scientists retards research progress, leading to superfluous and repetitive studies. This article summarizes clinical and experimental findings published about blast injuries and BINT following the wars of the 20th and 21th centuries. Moreover, it offers a personal view on potential factors interfering with the progress of BINT research working toward providing better diagnosis, treatment and rehabilitation for military personnel affected by blast exposure.

Major incident triage and the implementation of a new triage tool, the MPTT-24

Introduction

The Modified Physiological Triage Tool (MPTT) is a recently developed primary triage tool and in comparison with existing tools demonstrates the greatest sensitivity at predicting need for life-saving intervention (LSI) within both military and civilian populations. To improve its applicability, we proposed to increase the upper respiratory rate (RR) threshold to 24 breaths per minute (bpm) to produce the MPTT-24. Our aim was to conduct a feasibility analysis of the proposed MPTT-24, comparing its performance with the existing UK Military Sieve.

Method

A retrospective review of the Joint Theatre Trauma Registry (JTTR) and Trauma Audit Research Network (TARN) databases was performed for all adult (>18 years) patients presenting between 2006–2013 (JTTR) and 2014 (TARN). Patients were defined as priority one (P1) if they received one or more LSIs. Using first recorded hospital RR in isolation, sensitivity and specificity of the ≥24 bpm threshold was compared with the existing threshold (≥22 bpm) at predicting P1 status. Patients were then categorised as P1 or not-P1 by the MPTT, MPTT-24 and the UK Military Sieve.

Results

The MPTT and MPTT-24 outperformed existing UK methods of triage with a statistically significant (p<0.001) increase in sensitivity of between 25.5% and 29.5%. In both populations, the MPTT-24 demonstrated an absolute reduction in sensitivity with an increase in specificity when compared with the MPTT. A statistically significant difference was observed between the MPTT and MPTT-24 in the way they categorised TARN and JTTR cases as P1 (p<0.001).

Conclusions

When compared with the existing MPTT, the MPTT-24 allows for a more rapid triage assessment. Both continue to outperform existing methods of primary major incident triage and within the military setting, the slight increase in undertriage is offset by a reduction in overtriage. We recommend that the MPTT-24 be considered as a replacement to the existing UK Military Sieve.

The role of neutrophil gelatinase-associated lipocalin (NGAL) in the detection of blast lung injury in a military population

PURPOSE

To study the relationship between serum neutrophil gelatinase-associated lipocalin (NGAL) and military blast and gunshot wound (GSW) to establish whether potential exists for NGAL as a biomarker for blast lung injury (BLI).

METHOD

Patients from the intensive care unit (ICU) of the Role 3 Medical Treatment Facility at Camp Bastion, Helmand Province, Afghanistan were studied over a five month period commencing in 2012. Age, mechanism, trauma injury severity score (TRISS) and serum NGAL were recorded on ICU admission (NGAL1). Serum NGAL (NGAL2) and PaO₂/FiO₂ ratio (P/F ratio2) were recorded at 24h.

RESULTS

33 patients were injured by blast and 23 by GSW. NGAL1 inversely correlated with TRISS (p=0.020), pH (p=0.002) and P/F ratio 2 (p=0.009) overall. When data was stratified into blast and GSW, NGAL1 also inversely correlated with P/F ratio 2 in the blast injured group (p=0.008) but not GSW group (p=0.27).

CONCLUSION

Raised NGAL correlated with increased severity of injury (worse survival probability i.e. TRISS and low pH) in both patient groups. There was an inverse correlation between admission NGAL and a marker of blast lung injury (low P/F ratio) at 24h in blast injured group but not GSW group that warrants further investigation.

A critical literature review on primary blast thorax injury and their outcomes

Since World War II, researchers have been interested in exploring the injury mechanisms involved in primary blast on the thorax by using animal model surrogates. These studies were mostly concerned with the finding of the lung injury threshold, the relationship between the physical components of the air blast wave, and the biological response. Studies have also been conducted to investigate the effect of repeated blast exposures on the injury outcome threshold. This has led to several injury criteria, such as the Bowen curves based on pressure history's characteristics or the Axelsson Chest Wall Velocity Predictor that used measurement from the mammals' chest wall. This article aims at doing a critical literature review of this specific topic.

Major incident triage: Derivation and comparative analysis of the Modified Physiological Triage Tool (MPTT)

BACKGROUND

Triage is a key principle in the effective management at a major incident. There are at least three different triage systems in use worldwide and previous attempts to validate them, have revealed limited sensitivity. Within a civilian adult population, there has been no work to develop an improved system.

METHODS

A retrospective database review of the UK Joint Theatre Trauma Registry was performed for all adult patients (>18years) presenting to a deployed Military Treatment Facility between 2006 and 2013. Patients were defined as Priority One if they had received one or more life-saving interventions from a previously defined list. Using first recorded hospital physiological data (HR/RR/GCS), binary logistic regression models were used to derive optimum physiological ranges to predict need for life-saving intervention. This allowed for the derivation of the Modified Physiological Triage Tool-MPTT (GCS≥14, HR≥100, 12<RR≥22). A comparison of the MPTT and existing triage tools was then performed using sensitivities and specificities with 95% confidence intervals. Differences in performance were assessed for statistical significance using a McNemar test with Bonferroni correction.

RESULTS

Of 6095 patients, 3654 (60.0%) had complete data and were included in the study, with 1738 (47.6%) identified as priority one. Existing triage tools had a maximum sensitivity of 50.9% (Modified Military Sieve) and specificity of 98.4% (Careflight). The MPTT (sensitivity 69.9%, 95% CI 0.677-0.720, specificity 65.3%, 95% CI 0.632-0.675) showed an absolute increase in sensitivity over existing tools ranging from 19.0% (Modified Military Sieve) to 45.1% (Triage Sieve). There was a statistically significant difference between the performance (p<0.001) between the MPTT and the Modified Military Sieve.

DISCUSSION & CONCLUSION

The performance characteristics of the MPTT exceed existing major incident triage systems, whilst maintaining an appropriate rate of over-triage and minimising under-triage within the context of predicting the need for a life-saving intervention in a military setting. Further work is required to both prospectively validate this system and to identify its performance within a civilian environment, prior to recommending its use in the major incident setting.

The pattern of the Syrian refugee's injuries managed in King Abdullah University Hospital (Jordan)

OBJECTIVE

This study was conducted to assess the pattern, the magnitude, the severity, the distribution, and the results of the management of the injured Syrian refugees at King Abdullah University Hospital (KAUH).

METHODS

The medical records of 90 consecutive injured Syrian patients admitted to KAUH at the beginning of the Syrian conflict in 2012-2013 were reviewed. Information regarding the age, the sex, the antomical regions, the organs injured, the operations performed, the complications, and the weapons used were recorded.

RESULTS

Of the 90 cases, 86 (95.6%) were males and 4 (4.4%) were females. The age of patients ranged between 6 and 64 years with: 8 children (6-18) years old, 81 young adults (18-48) years old, and only 1elderly patient (64) years old. The distributions of the injuries were: 54.5% in extremities, 47.8% head and neck, 15.5% chest, and 14.4% abdomen with involvement of more than one injured region in several patients. The injuries were inflected by explosives in 49 cases, bullets in 45 cases, and both in 4 cases. The most frequently performed operations were: fractures fixations, fasciotomies, laparotomies, and craniotomies. Musculoskeletal and neurological deficits occurred in 11.1 and 8.8% of cases, respectively. The mortality rate was 2.2%. The average hospital stay was 19 days. The overall management costs were more than half million US Dollars.

CONCLUSIONS

Extremities and head and neck were the most injured regions. The referral from the forward centers and the procedures performed in our hospital improved the management outcomes. The management required long hospital stay and was costly.

Modelling primary blast lung injury: current capability and future direction

Primary blast lung injury frequently complicates military conflict and terrorist attacks on civilian populations. The fact that it occurs in areas of conflict or unpredictable mass casualty events makes clinical study in human casualties implausible. Research in this field is therefore reliant on the use of some form of biological or non-biological surrogate model. This article briefly reviews the modelling work undertaken in this field until now and describes the rationale behind the generation of an in silico physiological model.

Damage of vascular endothelial barrier induced by explosive blast and its clinical significance

In recent years, injuries induced by explosive blast have got more and more attention owing to weapon development and frequent terrorist activities. Tear, bleeding and edema of tissues and organs are the main manifestations of blast shock wave damage. Vascular endothelial barrier is the main defense of tissues and organs' integrity. This article aims to discuss possible mechanisms of endothelial barrier damage induced by explosive blast and main manifestations of blood brain barrier, bloodeair barrier, and intestinal vascular barrier impairments. In addition, the main regulatory factors of vascular permeability are also summarized so as to provide theoretical basis for prevention and cure of vascular endothelial barrier damage resulting from explosive blast.

Finite element modeling of blast lung injury in sheep

A detailed 3D finite element model (FEM) of the sheep thorax was developed to predict heterogeneous and volumetric lung injury due to blast. A shared node mesh of the sheep thorax was constructed from a computed tomography (CT) scan of a sheep cadaver, and while most material properties were taken from literature, an elastic-plastic material model was used for the ribs based on three-point bending experiments performed on sheep rib specimens. Anesthetized sheep were blasted in an enclosure, and blast overpressure data were collected using the blast test device (BTD), while surface lung injury was quantified during necropsy. Matching blasts were simulated using the sheep thorax FEM. Surface lung injury in the FEM was matched to pathology reports by setting a threshold value of the scalar output termed the strain product (maximum value of the dot product of strain and strain-rate vectors over all simulation time) in the surface elements. Volumetric lung injury was quantified by applying the threshold value to all elements in the model lungs, and a correlation was found between predicted volumetric injury and measured postblast lung weights. All predictions are made for the left and right lungs separately. This work represents a significant step toward the prediction of localized and heterogeneous blast lung injury, as well as volumetric injury, which was not recorded during field testing for sheep.

UK Triage the validation of a new tool to counter an evolving threat

INTRODUCTION

Major Incidents (MI) occur frequently and their unpredictable nature makes prospective research difficult and largely unethical. A key step in MI management is triage; the identification of the critically injured. Within a MI environment this is commonly performed using simple physiological ‘tools’, such as the Triage Sieve (TS). However the most commonly used tools appear to lack an evidence base. In a previous study, the authors used a military population to compare the performance of the TS to the Military Sieve (MS) at predicting need for Life-Saving Intervention (LSI). The MS differs only with the addition of a measurement of consciousness. The outcome from this study was that the MS outperformed the TS, but could be further improved with small changes to its physiological parameters, the Modified Military Sieve (MMS).

MATERIALS AND METHODS

Physiological data and interventions performed within the Emergency Department (ED) and Operating Theatre were prospectively collected for consecutive adult trauma patients (>18years) presenting to the ED at Camp Bastion, Afghanistan between March and September 2011. All patients receiving a LSI were considered Gold Standard Priority One. Patients were triaged using the TS, MS, MMS, START (ST) and Careflight (CF) triage tools. Sensitivities and specificities were estimated with 95% confidence intervals and differences were checked for statistical significance using a McNemar test with Bonferroni correction.

RESULTS

482 patients presented to the ED during the study period, sufficient data was recorded for 335 (71%) with 199 (59%) P1s. The MMS (sensitivity 68.3%, specificity 79.4%) showed an absolute increase in sensitivity over existing tools ranging from 5.0% (MS) to 23.6% (CF). There was a statistically significant difference (P = 0.0005) between the MMS and MS.

DISCUSSION

A key limitation to this study, is the use of a military cohort to validate the MMS, a tool which itself was developed using military data. The mechanism of injury also is unlikely to translate fully to the civilian population.

CONCLUSIONS

Within a military population, the MMS outperforms existing MI triage tools. Before it is recommended as a replacement to the existing TS in UK civilian practice, it needs to be tested in a civilian environment.

Haemodynamic changes in trauma

Trauma is the leading cause of death during the first four decades of life in the developed countries. Its haemodynamic response underpins the patient's initial ability to survive, and the response to treatment and subsequent morbidity and resolution. Trauma causes a number of insults including haemorrhage, tissue injury (nociception) and, predominantly, in military casualties, blast from explosions. This article discusses aspects of the haemodynamic responses to these insults and subsequent treatment. 'Simple' haemorrhage (blood loss without significant volume of tissue damage) causes a biphasic response: mean arterial blood pressure (MBP) is initially maintained by the baroreflex (tachycardia and increased vascular resistance, Phase 1), followed by a sudden decrease in MAP initiated by a second reflex (decrease in vascular resistance and bradycardia, Phase 2). Phase 2 may be protective. The response to tissue injury attenuates Phase 2 and may cause a deleterious haemodynamic redistribution that compromises blood flow to some vital organs. In contrast, thoracic blast exposure augments Phase 2 of the response to haemorrhage. However, hypoxaemia from lung injury limits the effectiveness of hypotensive resuscitation by augmenting the attendant shock state. An alternative strategy ('hybrid resuscitation') whereby tissue perfusion is increased after the first hour of hypotensive resuscitation by adopting a revised normotensive target may ameliorate these problems. Finally, morphine also attenuates Phase 2 of the response to haemorrhage in some, but not all, species and this is associated with poor outcome. The impact on human patients is currently unknown and is the subject of a current physiological investigation.

Development of an Animal Model for Burn-Blast Combined Injury and Cardiopulmonary System Changes in the Early Shock Stage

The purposes of this study were to establish an animal model for burn-blast combined injury research and elaborate cardiopulmonary system changes in the early shock stage. In this study, royal demolition explosive or RDX (hexagon, ring trimethylene nitramine) was used as an explosive source, and the injury conditions of the canine test subjects at various distances to the explosion (30, 50, and 70 cm) were observed by gross anatomy and pathology to determine a larger animal model of moderate blast injury. The canines were then subjected to a 35 % total body surface area (TBSA) full-thickness flame injury using napalm, which completed the development of a burn-blast combined injury model. Based on this model, the hemodynamic changes and arterial blood gas analysis after the burn-blast combined injury were measured to identify the cardiopulmonary system characteristics. In this research, RDX explosion and flame injury were used to develop a severe burn-blast injury animal model that was stable, close to reality, and easily controllable. The hemodynamic and arterial blood gas changes in the canine subjects after burn-blast injury changed distinctly from the burn and blast injuries. Blood pressure and cardiac output fluctuated, and the preload was significantly reduced, whereas the afterload significantly increased. Meanwhile, the oxygen saturation (SO2) decreased markedly with carbon dioxide partial pressure (PCO2), and lactic acid (Lac) rose, and oxygen partial pressure (PO2) reduced. These changes suggested that immediate clinical treatment is important during burn-blast injury both to stabilize cardiac function and supply blood volume and to reduce the vascular permeability, thereby preventing acute pneumonedema or other complications.

Blast exposure causes early and persistent aberrant phospho- and cleaved-tau expression in a murine model of mild blast-induced traumatic brain injury

Mild traumatic brain injury (mTBI) is considered the 'signature injury' of combat veterans that have served during the wars in Iraq and Afghanistan. This prevalence of mTBI is due in part to the common exposure to high explosive blasts in combat zones. In addition to the threats of blunt impact trauma caused by flying objects and the head itself being propelled against objects, the primary blast overpressure (BOP) generated by high explosives is capable of injuring the brain. Compared to other means of causing TBI, the pathophysiology of mild-to-moderate BOP is less well understood. To study the consequences of BOP exposure in mice, we employed a well-established approach using a compressed gas-driven shock tube that recapitulates battlefield-relevant open-field BOP. We found that 24 hours post-blast a single mild BOP provoked elevation of multiple phospho- and cleaved-tau species in neurons, as well as elevating manganese superoxide-dismutase (MnSOD or SOD2) levels, a cellular response to oxidative stress. In hippocampus, aberrant tau species persisted for at least 30 days post-exposure, while SOD2 levels returned to sham control levels. These findings suggest that elevated phospho- and cleaved-tau species may be among the initiating pathologic processes induced by mild blast exposure. These findings may have important implications for efforts to prevent blast-induced insults to the brain from progressing into long-term neurodegenerative disease processes.

Assessment of the perioperative period in civilians injured in the Syrian Civil War

BACKGROUND

wars and its challenges have historically afflicted humanity. In Syria, severe injuries occurred due to firearms and explosives used in the war between government forces and civilians for a period of over 2 years.

MATERIALS AND METHODS

the study included 364 cases, who were admitted to Mustafa Kemal University Hospital, Medicine School (Hatay, Turkey), and underwent surgery. Survivors and non-survivors were compared regarding injury site, injury type and number of transfusions given. The mortality rate found in this study was also compared to those reported in other civil wars.

RESULTS

the mean age was 29 (3-68) years. Major sites of injury included extremities (56.0%), head (20.1%), abdomen (16.2%), vascular structures (4.4%) and thorax (3.3%). Injury types included firearm injury (64.4%), blast injury (34.4%) and miscellaneous injuries (1.2%). Survival rate was 89.6% while mortality rate was 10.4%. A significant difference was observed between mortality rates in this study and those reported for the Bosnia and Lebanon civil wars; and the difference became extremely prominent when compared to mortality rates reported for Vietnam and Afghanistan civil wars.

CONCLUSION

among injuries related to war, the highest rate of mortality was observed in head-neck, abdomen and vascular injuries. We believe that the higher mortality rate in the Syrian Civil War, compared to the Bosnia, Vietnam, Lebanon and Afghanistan wars, is due to seeing civilians as a direct target during war.

Combat Casualty Care research programme

The Combat Casualty Care research programme is an integrated suite of projects designed to address Defence Medical Services' research needs for casualty care. The programme covers a broad spectrum of topics ranging from the pathophysiological and immunological impact of military relevant injuries to the effects of these disturbances on the response to early treatment. Dstl Porton Down has a long history of studying military injuries and has developed models, both in vivo and physical, to address the research needs. The work is conducted in close collaboration with clinical colleagues at the Royal Centre for Defence Medicine who have direct experience of the clinical issues faced by combat casualties and insights into the potential clinical implications of emerging strategies. This article reviews progress in research areas spanning forward resuscitation, with a particular focus on blast-related injuries, trauma coagulopathy, effects of drugs on the response to haemorrhage and deployed research. A significant 'value added' component has been the underpinning of higher degrees for seconded military clinicians at Dstl Porton Down who have made a valuable contribution to the overall programme.