Effect of blast orientation, multi-point blasts, and repetitive blasts on brain injury.

Explosions in the battlefield can result in brain damage. Research on the effects of shock waves on brain tissue mainly focuses on the effects of single-orientation blast waves, while there have been few studies on the dynamic response of the human brain to directional explosions in different planes, multi-point explosions and repetitive explosions. Therefore, the brain tissue response and the intracranial pressure (ICP) caused by different blast loadings were numerically simulated using the CONWEP method. In the study of the blast in different directions, the lateral explosion blast wave was found to cause greater ICP than did blasts from other directions. When multi-point explosions occurred in the sagittal plane simultaneously, the ICP in the temporal lobe increased by 37.8 % and the ICP in the parietal lobe decreased by 17.6 %. When multi-point explosions occurred in the horizontal plane, the ICP in the frontal lobe increased by 61.8 % and the ICP in the temporal lobe increased by 12.2 %. In a study of repetitive explosions, the maximum ICP of the second blast increased by 40.6 % over that of the first blast, and that of the third blast increased by 61.2 % over that of the second blast. The ICP on the brain tissue from repetitive blasts can exceed 200 % of that of a single explosion blast wave.

Impact of repeated blast exposure on active-duty United States Special Operations Forces.

United States (US) Special Operations Forces (SOF) are frequently exposed to explosive blasts in training and combat, but the effects of repeated blast exposure (RBE) on SOF brain health are incompletely understood. Furthermore, there is no diagnostic test to detect brain injury from RBE. As a result, SOF personnel may experience cognitive, physical, and psychological symptoms for which the cause is never identified, and they may return to training or combat during a period of brain vulnerability. In 30 active-duty US SOF, we assessed the relationship between cumulative blast exposure and cognitive performance, psychological health, physical symptoms, blood proteomics, and neuroimaging measures (Connectome structural and diffusion MRI, 7 Tesla functional MRI, [11C]PBR28 translocator protein [TSPO] positron emission tomography [PET]-MRI, and [18F]MK6240 tau PET-MRI), adjusting for age, combat exposure, and blunt head trauma. Higher blast exposure was associated with increased cortical thickness in the left rostral anterior cingulate cortex (rACC), a finding that remained significant after multiple comparison correction. In uncorrected analyses, higher blast exposure was associated with worse health-related quality of life, decreased functional connectivity in the executive control network, decreased TSPO signal in the right rACC, and increased cortical thickness in the right rACC, right insula, and right medial orbitofrontal cortex-nodes of the executive control, salience, and default mode networks. These observations suggest that the rACC may be susceptible to blast overpressure and that a multimodal, network-based diagnostic approach has the potential to detect brain injury associated with RBE in active-duty SOF.

Evaluating emergency response at a hospital near the Gaza border within 24 h of increased conflict.

BACKGROUND: Frontline hospitals near active hostilities face unique challenges in delivering emergency care amid threats to infrastructure and personnel safety. Existing literature focuses on individual aspects like mass casualty protocols or medical neutrality, with limited analysis of operating acute services directly under fire. OBJECTIVES: To describe the experience of a hospital situated meters from hostilities and analyze strategies implemented for triage, expanding surge capacity, and maintaining continuity of care during attacks with limited medical staff availability due to hazardous conditions. A focus will be placed on assessing how the hospital functioned and adapted care delivery models in the event of staffing limitations preventing all teams from arriving on site. METHODS: A retrospective case study was conducted of patient records from Barzilai University Medical Center at Ashkelon (BUMCA) Medical Center in Israel within the first 24 h after escalated conflict began on October 7, 2023. Data on 232 admissions were analyzed regarding demographics, treatment protocols, time to disposition, and mortality. Missile alert data correlated patient surges to attacks. Statistical and geospatial analyses were performed. RESULTS: Patients predominantly male soldiers exhibited blast/multisystem trauma. Patient surges at the hospital were found to be correlated with the detection of incoming missile attacks from Gaza within 60 min of launch. While 131 (56%) patients were discharged and 55 (24%) transferred within 24 h, probabilities of survival declined over time reflecting injury severity limitations. 31 deaths occurred from severe presentation. CONCLUSION: Insights gleaned provide a compelling case study on managing mass casualties at the true frontlines. By disseminating BUMCA's trauma response experience, strategies can strengthen frontline hospital protocols optimizing emergency care delivery during hazardous armed conflicts through dynamic surge capacity expansion, early intervention prioritization, and infrastructure/personnel protection measures informed by risks.

Risk of burns in pressure cooker usage: a comprehensive analysis of explosive injuries.

BACKGROUND: Despite the widespread use of pressure cookers for quick and efficient cooking, literature has insufficiently highlighted the potential dangers resulting from inappropriate handling. This study aims to provide a comprehensive overview of 32 patients who presented with pressure cooker burns, emphasizing the serious risks associated with their misuse. METHODS: Retrospective data were collected from patients admitted to Bagcilar Training and Research Hospital Burn Center between 2017 and 2020 with pressure cooker burns in Türkiye. Data encompassed patient characteristics, burn causes, locations, severities, treatments, and clinical outcomes. RESULTS: The study included 32 patients (29 female/3 male) with a mean age of 42.3 (8-83). Patients were categorized based on burn areas, revealing associated injuries such as ocular (34.3%) and ear injuries (6.25%). The average hospital stay was 10.5 days [2-37]. While five pressure cookers exploded due to product-related issues, 26 explosions resulted from user errors (15.6%/81.2%). Importantly, no mortality was observed among the patients. CONCLUSION: While pressure cookers facilitate rapid food preparation, this study underscores the severe risks arising from product or usage errors. This study emphasizes the need for more effective usage instructions and increased awareness about pressure cookers to prevent burn risks. We anticipate that educational programs focused on safe pressure cooker use could significantly reduce the incidence of serious injuries.

Study protocol: Identifying transcriptional regulatory alterations of chronic effects of blast and disturbed sleep in United States Veterans.

Injury related to blast exposure dramatically rose during post-911 era military conflicts in Iraq and Afghanistan. Mild traumatic brain injury (mTBI) is among the most common injuries following blast, an exposure that may not result in a definitive physiologic marker (e.g., loss of consciousness). Recent research suggests that exposure to low level blasts and, more specifically repetitive blast exposure (RBE), which may be subconcussive in nature, may also impact long term physiologic and psychological outcomes, though findings have been mixed. For military personnel, blast-related injuries often occur in chaotic settings (e.g., combat), which create challenges in the immediate assessment of related-injuries, as well as acute and post-acute sequelae. As such, alternate means of identifying blast-related injuries are needed. Results from previous work suggest that epigenetic markers, such as DNA methylation, may provide a potential stable biomarker of cumulative blast exposure that can persist over time. However, more research regarding blast exposure and associations with short- and long-term sequelae is needed. Here we present the protocol for an observational study that will be completed in two phases: Phase 1 will address blast exposure among Active Duty Personnel and Phase 2 will focus on long term sequelae and biological signatures among Veterans who served in the recent conflicts and were exposed to repeated blast events as part of their military occupation. Phase 2 will be the focus of this paper. We hypothesize that Veterans will exhibit similar differentially methylated regions (DMRs) associated with changes in sleep and other psychological and physical metrics, as observed with Active Duty Personnel. Additional analyses will be conducted to compare DMRs between Phase 1 and 2 cohorts, as well as self-reported psychological and physical symptoms. This comparison between Service Members and Veterans will allow for exploration regarding the natural history of blast exposure in a quasi-longitudinal manner. Findings from this study are expected to provide additional evidence for repetitive blast-related physiologic changes associated with long-term neurobehavioral symptoms. It is expected that findings will provide foundational data for the development of effective interventions following RBE that could lead to improved long-term physical and psychological health.

Weight-Drop Method for Inducing Closed Head Diffuse Traumatic Brain Injury.

Traumatic brain injury (TBI) is one of the foremost causes of disability and death globally. Prerequisites for successful therapy of disabilities associated with TBI involved improved knowledge of the neurobiology of TBI, measurement of quantitative changes in recovery dynamics brought about by therapy, and the translation of quantitative methodologies and techniques that were successful in tracking recovery in preclinical models to human TBI. Frequently used animal models of TBI in research and development include controlled cortical impact, fluid percussion injury, blast injury, penetrating blast brain injury, and weight-drop impact acceleration models. Preclinical models of TBI benefit from controlled injury settings and the best prospects for biometric quantification of injury and therapy-induced gradual recovery from disabilities. Impact acceleration closed head TBI paradigm causes diffuse TBI (DTBI) without substantial focal brain lesions in rats. DTBI is linked to a significant rate of death, morbidity, and long-term disability. DTBI is difficult to diagnose at the time of hospitalization with imaging techniques making it challenging to take prompt therapeutic action. The weight-drop method without craniotomy is an impact acceleration closed head DTBI model that is used to induce mild/moderate diffuse brain injuries in rodents. Additionally, we have characterized neuropathological and neurobehavioral outcomes of the weight-drop model without craniotomy for inducing closed head DTBI of graded severity with a range of mass of weights (50-450 gm). This chapter also discusses techniques and protocols for measuring numerous functional disabilities and pathological changes in the brain brought on by DTBI.

Association of Blast Exposure in Military Breaching with Intestinal Permeability Blood Biomarkers Associated with Leaky Gut.

Injuries and subclinical effects from exposure to blasts are of significant concern in military operational settings, including tactical training, and are associated with self-reported concussion-like symptomology and physiological changes such as increased intestinal permeability (IP), which was investigated in this study. Time-series gene expression and IP biomarker data were generated from "breachers" exposed to controlled, low-level explosive blast during training. Samples from 30 male participants at pre-, post-, and follow-up blast exposure the next day were assayed via RNA-seq and ELISA. A battery of symptom data was also collected at each of these time points that acutely showed elevated symptom reporting related to headache, concentration, dizziness, and taking longer to think, dissipating ~16 h following blast exposure. Evidence for bacterial translocation into circulation following blast exposure was detected by significant stepwise increase in microbial diversity (measured via alpha-diversity p = 0.049). Alterations in levels of IP protein biomarkers (i.e., Zonulin, LBP, Claudin-3, I-FABP) assessed in a subset of these participants (n = 23) further evidenced blast exposure associates with IP. The observed symptom profile was consistent with mild traumatic brain injury and was further associated with changes in bacterial translocation and intestinal permeability, suggesting that IP may be linked to a decrease in cognitive functioning. These preliminary findings show for the first time within real-world military operational settings that exposures to blast can contribute to IP.

Contemporary History of Spine Fractures Following Deck-Slap Injury: From Deck Blast During World War II Naval Battles to Axial Trauma During Touristic Speedboat Sea Cruise in 21st Century.

In large-scale naval battles during World War II, sailors sometimes sustained serious lower limb injuries when explosion blast of sea mines was transmitted from underneath through the metal deck of the ships. Some of these sailors were thrown in the air due to the blast and sustained axial trauma of the spine when they landed on the hard deck, which was thus called a deck slap by Captain Joseph Barr in 1946, among others. Nowadays, this peculiar mechanism has shifted to the civilian setting. Tourists unaware of the danger may sustain spine compression fractures when they sit at the bow of speed boats while underway on a calm sea. When the craft unexpectedly crosses the wake of another ship, tourists are thrown a few feet in the air before suffering a hard landing on their buttocks. This historical vignette is presented as a preventive message to help to reduce this poorly known yet avoidable "summer wave of vertebral fractures."

Investigating neuropathological changes and underlying neurobiological mechanisms in the early stages of primary blast-induced traumatic brain injury: Insights from a rat model.

The utilization of explosives and chemicals has resulted in a rise in blast-induced traumatic brain injury (bTBI) in recent times. However, there is a dearth of diagnostic biomarkers and therapeutic targets for bTBI due to a limited understanding of biological mechanisms, particularly in the early stages. The objective of this study was to examine the early neuropathological characteristics and underlying biological mechanisms of primary bTBI. A total of 83 Sprague Dawley rats were employed, with their heads subjected to a blast shockwave of peak overpressure ranging from 172 to 421 kPa in the GI, GII, and GIII groups within a closed shock tube, while the body was shielded. Neuromotor dysfunctions, morphological changes, and neuropathological alterations were detected through modified neurologic severity scores, brain water content analysis, MRI scans, histological, TUNEL, and caspase-3 immunohistochemical staining. In addition, label-free quantitative (LFQ)-proteomics was utilized to investigate the biological mechanisms associated with the observed neuropathology. Notably, no evident damage was discernible in the GII and GI groups, whereas mild brain injury was observed in the GIII group. Neuropathological features of bTBI were characterized by morphologic changes, including neuronal injury and apoptosis, cerebral edema, and cerebrovascular injury in the shockwave's path. Subsequently, 3153 proteins were identified and quantified in the GIII group, with subsequent enriched neurological responses consistent with pathological findings. Further analysis revealed that signaling pathways such as relaxin signaling, hippo signaling, gap junction, chemokine signaling, and sphingolipid signaling, as well as hub proteins including Prkacb, Adcy5, and various G-protein subunits (Gnai2, Gnai3, Gnao1, Gnb1, Gnb2, Gnb4, and Gnb5), were closely associated with the observed neuropathology. The expression of hub proteins was confirmed via Western blotting. Accordingly, this study proposes signaling pathways and key proteins that exhibit sensitivity to brain injury and are correlated with the early pathologies of bTBI. Furthermore, it highlights the significance of G-protein subunits in bTBI pathophysiology, thereby establishing a theoretical foundation for early diagnosis and treatment strategies for primary bTBI.

Periarticular blast wounds without fracture a prospective case series.

BACKGROUND: During the wars in Afghanistan and Iraq most injuries to service members involved the musculoskeletal system. These wounds often occurred around joints, and in some cases result in traumatic arthrotomy-a diagnosis that is not always clear, especially when there is no concomitant articular fracture. The aim of the present study is to evaluate the diagnosis and treatment of peri-articular blast injuries without fracture. METHODS: The study cohort included 12 consecutive patients (12 involved extremities) who sustained peri-articular blast wounds of the extremities without fractures. The diagnosis of penetrating articular injury was based on clinical examination, radiographic findings, or aspiration. A peri-articular wound was defined as any wound, or radio-opaque blast fragment, within 5 cm of a joint. The New Injury Severity Score (NISS) was calculated for each patient. Four patients had upper, and 8 patients had lower extremity injuries. Nine of 12 patients had joint capsular penetration and underwent joint irrigation and debridement. RESULTS: Two patients had retained intra-articular metal fragments. One patient had soft tissue blast wounds within 5 cm of a joint but did not have joint capsule penetration. There were no significant differences (p = 0.23) between the distribution of wounds to upper versus lower extremities. However, there were a significantly greater number of blast injuries attributed to Improvised Explosive Devices (IEDs) than from other blast mechanisms (p = 0.01). CONCLUSION: Extremity blast injuries in the vicinity of joints involving only soft tissues present a unique challenge in surgical management. A high index of suspicion should be maintained for joint capsular penetration so that intra-articular injuries may be appropriately treated.

Ocular Firework Injuries among Patients Presented to the Emergency Department During Festival Season in a Tertiary Eye Hospital.

Introduction: Fireworks can cause severe ocular injuries which can be prevented if used with proper precautions. It causes not only mechanical injuries but also thermal and chemical injuries. This study aimed to find out the prevalence of ocular firework injuries among patients presented to the emergency department during festival season in a tertiary eye hospital. Methods: This is a descriptive cross-sectional study done among patients presenting in the emergency department of a tertiary eye hospital after obtaining ethical approval from the Institutional Review Committee. Data of patients from medical records between 26 October 2021 to 28 November 2021 and 15 October 2022 to 17 November 2022 was collected. A convenience sampling method was used. The point estimate was calculated at a 95% Confidence Interval. Results: Among 132 patients, the prevalence of ocular firework injuries was seen in 73 (55.30%) (46.82-63.78, 95% Confidence Interval). Closed globe injury was mostly observed in 56 (76.71%) patients with ocular injuries. The most common age group affected was those less than 30 years old 54 (73.97%). Conclusions: The prevalence of ocular firework injuries was found to be lower than other studies done in similar settings. Protective measures should be used to prevent ocular injuries. A public awareness program needs to be launched before such festivals. Keywords: festivals; injuries; prevalence.

Cutaneous burn injury represents a major risk factor for the development of traumatic ectopic bone formation following blast-related extremity injury.

Blast-related traumatic heterotopic ossification (tHO) impacts clinical outcomes in combat-injured patients, leading to delayed wound healing, inflammatory complications, and reduced quality of life. Blast injured patients often have significant burns. This study investigated whether a partial thickness thermal burn injury exacerbates blast-related tHO in a clinically relevant polytrauma animal model. Adult male Sprague Dawley rats were subjected to an established model involving a whole-body blast overpressure exposure (BOP), complex extremity trauma followed by hind limb amputation (CET) followed by the addition of a 10 % total body surface area (TBSA) second degree thermal burn (BU). Micro-CT scans on post-operative day 56 showed a significant increase in HO volume in the CET + BU as compared to the CET alone injury group (p < .0001; 22.83 ± 3.41 mm3 vs 4.84 ± 5.77 mm3). Additionally, CET + BU concomitant with BOP significantly increased HO (p < .0001; 34.95 ± 7.71 mm3) as compared to CET + BU alone, confirming BOP has a further synergistic effect. No HO was detectable in rats in the absence of CET. Serum analysis revealed similar significant elevated (p < .0001) levels of pro-inflammatory markers (Cxcl1 and Il6) at 6 h post-injury (hpi) in the CET + BU and BOP + CET + BU injury groups as compared to naïve baseline values. Real-time qPCR demonstrated similar levels of chondrogenic and osteogenic gene expression in muscle tissue at the site of injury at 168 hpi in both the CET + BU and BOP+CET + BU injury groups. These results support the hypothesis that a 10 % TBSA thermal burn markedly enhances tHO following acute musculoskeletal extremity injury in the presence and absence of blast overpressure. Furthermore, the influence of BOP on tHO cannot be accounted for either in regards to systemic inflammation induced from remote injury or inflammatory-osteo-chondrogenic expression changes local to the musculoskeletal trauma, suggesting that another mechanism beyond BOP and BU synergistic effects are at play. Therefore, these findings warrant future investigations to explore other mechanisms by which blast and burn influence tHO, and testing prophylactic measures to mitigate the local and systemic inflammatory effects of these injuries on development of HO.

In Silico Investigation of Biomechanical Response of a Human Brain Subjected to Primary Blast.

The brain response to the explosion-induced primary blast waves is actively sought. Over the past decade, reasonable progress has been made in the fundamental understanding of blast traumatic brain injury (bTBI) using head surrogates and animal models. Yet, the current understanding of how blast waves interact with human is in nascent stages, primarily due to the lack of data in human. The biomechanical response in human is critically required to faithfully establish the connection to the aforementioned bTBI models. In this work, the biomechanical cascade of the brain under a primary blast has been elucidated using a detailed, full-body human model. The full-body model allowed us to holistically probe short- (<5 ms) and long-term (200 ms) brain responses. The full-body model has been extensively validated against impact loading in the past. We have further validated the head model against blast loading. We have also incorporated the structural anisotropy of the brain white matter. The blast wave transmission, and linear and rotational motion of the head were dominant pathways for the loading of the brain, and these loading paradigms generated distinct biomechanical fields within the brain. Blast transmission and linear motion of the head governed the volumetric response, whereas the rotational motion of the head governed the deviatoric response. Blast induced head rotation alone produced diffuse injury pattern in white matter fiber tracts. The biomechanical response under blast was comparable to the impact event. These insights will augment laboratory and clinical investigations of bTBI and help devise better blast mitigation strategies.

A systematic review of otologic injuries sustained in civilian terrorist explosions.

PURPOSE: Determine the prevalence of otological symptoms and tympanic membrane perforation, healing rates of tympanic membrane perforation with surgical and conservative management, and hearing function in civilian victims of terrorist explosions. METHODS: A systematic review was conducted with searches on Medline, Embase, EMCare and CINAHL for publications between the 1st January 1945 and 26th May 2023. Studies with quantitative data addressing our aims were included. This review is registered with PROSPERO: CRD42020166768. Among 2611 studies screened, 18 studies comprising prospective and retrospective cohort studies were included. RESULTS: The percentage of eardrums perforated in patients admitted to hospital, under ENT follow up and attending the emergency department is 69.0% (CI 55.5-80.5%), 38.7% (CI 19.0-63.0%, I2 0.715%) and 21.0% (CI 11.9-34.3%, I2 0.718%) respectively. Perforated eardrums heal spontaneously in 62.9% (CI 50.4-73.8%, I2 0.687%) of cases and in 88.8% (CI 75.9-96.3%, I2 0.500%) of cases after surgery. Common symptoms present within one month of bombings are tinnitus 84.7% (CI 70.0-92.9%, I2 0.506%), hearing loss 83.0% (CI 64.5-92.9%, I2 0.505%) and ear fullness 59.7% (CI 13.4-93.4%, I2 0.719). Symptomatic status between one and six months commonly include no symptoms 57.5% (CI 46.0-68.3%), hearing loss 35.4% (CI 21.8-51.8%, I2 0.673%) and tinnitus 15.6% (CI 4.9-40.0%, I2 0.500%). Within one month of bombings, the most common hearing abnormality is sensorineural hearing loss affecting 26.9% (CI 16.9-40.1%, I2 0.689%) of ears 43.5% (CI 33.4-54.2%, I2 0.500) of people. CONCLUSION: Tympanic membrane perforation, subjective hearing loss, tinnitus, ear fullness and sensorineural hearing loss are common sequelae of civilian terrorist explosions.