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PloS One 2024Since the 19th century, underwater explosions have posed a significant threat to service members. While there have been attempts to establish injury criteria for the...
Since the 19th century, underwater explosions have posed a significant threat to service members. While there have been attempts to establish injury criteria for the most vulnerable organs, namely the lungs, existing criteria are highly variable due to insufficient human data and the corresponding inability to understand the underlying injury mechanisms. This study presents an experimental characterization of isolated human lung dynamics during simulated exposure to underwater shock waves. We found that the large acoustic impedance at the surface of the lung severely attenuated transmission of the shock wave into the lungs. However, the shock wave initiated large bulk pressure-volume cycles that are distinct from the response of the solid organs under similar loading. These pressure-volume cycles are due to compression of the contained gas, which we modeled with the Rayleigh-Plesset equation. The extent of these lung dynamics was dependent on physical confinement, which in real underwater blast conditions is influenced by factors such as rib cage properties and donned equipment. Findings demonstrate a potential causal mechanism for implosion injuries, which has significant implications for the understanding of primary blast lung injury due to underwater blast exposures.
Topics: Humans; Lung; Blast Injuries; Explosions; Lung Injury; Male; Pressure; High-Energy Shock Waves
PubMed: 38748668
DOI: 10.1371/journal.pone.0303325 -
Diagnostic and Interventional Radiology... May 2024To evaluate the efficacy of staged full-length balloon-assisted maturation (BAM) for the maturation of arteriovenous fistulas (AVFs) on entire segmental veins, including...
PURPOSE
To evaluate the efficacy of staged full-length balloon-assisted maturation (BAM) for the maturation of arteriovenous fistulas (AVFs) on entire segmental veins, including stenosis, causing primary AVF failure.
METHODS
This study included patients who underwent AVF surgery using an autogenous vein between February 2020 and June 2021 and received staged angioplasty with a full-length balloon catheter. To minimize balloon overlap and the risk of barotrauma to the immature vein, serial-staged upsizing balloon angioplasty with a long balloon catheter covering the entire vein segment was employed approximately 2 weeks apart.
RESULTS
Twenty-three patients (mean age, 69.50 years; mean follow-up, 620.62 days) with average diameters of the radial artery and cephalic vein at 2.14 ± 0.5 mm and 2.43 ± 0.5 mm, respectively, were enrolled. In the first procedure, the average AVF diameter and flow were 4.03 ± 0.57 mm and 438.08 ± 220.95 mL/min, respectively, with juxta-anastomotic stenosis (JAS) present in 61.5% of cases. After staged full-length BAM, the average fistula diameter and flow improved to 5.95 ± 0.86 mm and 717.52 ± 305.95 mL/min, respectively. Maturation was achieved in 87% of the cases. No hematomas or ruptures occurred around the arterialized veins. Despite successful maturation and cannulation, 65.2% of the patients required additional percutaneous transluminal angioplasty (PTA) during the follow-up period. The necessity for PTA was determined by the presence of JAS prior to the first staged full-length BAM, with an odds ratio of 11.74 (95% confidence interval: 1.31-104.96, = 0.03).
CONCLUSION
Staged full-length BAM can be safely used in patients with small veins requiring further maturation. Most patients achieved successful cannulation following maturation without post-procedural complications.
CLINICAL SIGNIFICANCE
Staged full-length BAM is a safe and effective method for enhancing maturation in patients with underdeveloped small veins.
PubMed: 38738746
DOI: 10.4274/dir.2024.232607 -
Advanced Emergency Nursing JournalEnsuring correct placement of the endotracheal tube (ETT) during intubation is an important step to avoid complications. Appropriate placement of the ETT can be... (Review)
Review
Ensuring correct placement of the endotracheal tube (ETT) during intubation is an important step to avoid complications. Appropriate placement of the ETT can be challenging and, if done incorrectly, can lead to complications such as hypoxemia, atelectasis, hyperinflation, barotrauma, cardiovascular instability, end organ damage, and even death. Although several procedures exist to help assess ETT confirmation, all have limitations, are not always reliable, and vary in their degree of accuracy. Point-of-care ultrasound (POCUS) has emerged as a useful tool in the emergency department for quick diagnosis and treatment of many emergency conditions (Gonzalez et al., 2020). The purpose of this paper is to describe a systematic approach for the emergency nurse practitioner to use POCUS to assess proper endotracheal placement and the positioning within the trachea based on prior studies that compare this modality to traditional ones.
Topics: Humans; Intubation, Intratracheal; Point-of-Care Systems; Nurse Practitioners; Ultrasonography; Emergency Service, Hospital; Emergency Nursing
PubMed: 38736097
DOI: 10.1097/TME.0000000000000514 -
Animals : An Open Access Journal From... Apr 2024Osteolytic lesions in loggerhead sea turtles () during rehabilitation are attributed to multiple causes, including gas embolism, hypothermia, and osteomyelitis due to...
Osteolytic lesions in loggerhead sea turtles () during rehabilitation are attributed to multiple causes, including gas embolism, hypothermia, and osteomyelitis due to bacterial or fungal infection. This study reports the appearance of osteolytic lesions in a sub-adult loggerhead sea turtle with involvement of the right fore and hind flippers, visible swelling of the elbow and knee joints, and accompanied by lameness after 45 days of rehabilitation. Radiographs and computed tomography revealed multiple lytic bone lesions. This was the fourth rehabilitation admission of the turtle after being accidentally captured by trawler ships (bycatch) in 2019, 2020, 2022, and 2023. Potential causes were dysbaric osteonecrosis due to a past decompression sickness event and hypothermia with osteomyelitis from bacterial infection. Blood cultures and antibiotic susceptibility testing led to the isolation of responsive to enrofloxacin. This study investigates extensive fore and hind flipper involvement in a sub-adult loggerhead turtle, aiming to determine causes and risk factors. The pathogenesis and significance of these lesions is discussed.
PubMed: 38731321
DOI: 10.3390/ani14091317 -
Current Sports Medicine Reports May 2024Breath-hold divers, also known as freedivers, are at risk of specific injuries that are unique from those of surface swimmers and compressed air divers. Using... (Review)
Review
Breath-hold divers, also known as freedivers, are at risk of specific injuries that are unique from those of surface swimmers and compressed air divers. Using peer-reviewed scientific research and expert opinion, we created a guide for medical providers managing breath-hold diving injuries in the field. Hypoxia induced by prolonged apnea and increased oxygen uptake can result in an impaired mental state that can manifest as involuntary movements or full loss of consciousness. Negative pressure barotrauma secondary to airspace collapse can lead to edema and/or hemorrhage. Positive pressure barotrauma secondary to overexpansion of airspaces can result in gas embolism or air entry into tissues and organs. Inert gas loading into tissues from prolonged deep dives or repetitive shallow dives with short surface intervals can lead to decompression sickness. Inert gas narcosis at depth is commonly described as an altered state similar to that experienced by compressed air divers. Asymptomatic cardiac arrhythmias are common during apnea, normally reversing shortly after normal ventilation resumes. The methods of glossopharyngeal breathing (insufflation and exsufflation) can add to the risk of pulmonary overinflation barotrauma or loss of consciousness from decreased cardiac preload. This guide also includes information for medical providers who are tasked with providing medical support at an organized breath-hold diving event with a list of suggested equipment to facilitate diagnosis and treatment outside of the hospital setting.
Topics: Humans; Diving; Breath Holding; Barotrauma; Decompression Sickness; Hypoxia; Inert Gas Narcosis
PubMed: 38709946
DOI: 10.1249/JSR.0000000000001168 -
Lancet (London, England) May 2024
Topics: Humans; Blast Injuries; Explosions; Delivery of Health Care; Weapons
PubMed: 38705156
DOI: 10.1016/S0140-6736(24)00913-9 -
Medical Engineering & Physics May 2024Explosions 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...
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.
Topics: Explosions; Humans; Brain Injuries; Intracranial Pressure; Blast Injuries; Brain
PubMed: 38692763
DOI: 10.1016/j.medengphy.2024.104163 -
American Journal of Otolaryngology 2024Barometric pressure changes during flight or diving may cause facial barotrauma. Neuropathy of the fifth (CN5) or the seventh (CN7) cranial nerves is a rare... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Barometric pressure changes during flight or diving may cause facial barotrauma. Neuropathy of the fifth (CN5) or the seventh (CN7) cranial nerves is a rare manifestation of this condition. The aim of this study was to analyze risk factors for baroneuropathies of CN5 and CN7.
METHODS
A search of PubMed and Cochrane Library databases was conducted to identify all published cases of CN5 and CN7 neuropathies. Only original case reports and series that documented events of neuropathies associated with the trigeminal nerve or facial nerve while flying, diving, or mountain climbing were included. Assessed variables included sex, medical history, age, setting (flight or diving), atmospheric pressure changes, number of episodes, symptoms, treatment, and recovery.
RESULTS
We identified a total of 48 articles described >125 episodes in 67 patients. Mean age was 33.5 ± 12.1 years with a male predominance (76.1 %). Cases were equally distributed between flight and diving (50.7 %, 46.3 %, respectively). CN5 involvement was observed in 77.6 % of patients, with ear pain and facial numbness as the most common symptoms. The latter was correlated with positive otolaryngology medical history. CN7 was involved in 88.1 % of patients. Flying, as opposed to diving was correlated with spontaneous resolution of symptoms (86.7 % vs. 42.3 % of cases resolved spontaneously, respectively, p = 0.001).
CONCLUSIONS
Flight is an equal risk factor to diving with respect to CN5 and CN7 barotrauma. Involvement of CN7 was observed in most cases, but possibly due to report-bias. Positive medical history is a risk factor for facial numbness.
Topics: Humans; Barotrauma; Risk Factors; Atmospheric Pressure; Diving; Male; Trigeminal Nerve Diseases; Female; Facial Nerve Diseases; Adult
PubMed: 38692074
DOI: 10.1016/j.amjoto.2024.104311 -
Experimental Eye Research Jul 2024Visual disorders are common even after mild traumatic brain injury (mTBI) or blast exposure. The cost of blast-induced vision loss in civilians, military personnel, and... (Review)
Review
Visual disorders are common even after mild traumatic brain injury (mTBI) or blast exposure. The cost of blast-induced vision loss in civilians, military personnel, and veterans is significant. The visual consequences of blasts associated with TBI are elusive. Active military personnel and veterans report various ocular pathologies including corneal disorders post-combat blasts. The wars and conflicts in Afghanistan, Iraq, Syria, and Ukraine have significantly increased the number of corneal and other ocular disorders among military personnel and veterans. Binocular vision, visual fields, and other visual functions could be impaired following blast-mediated TBI. Blast-associated injuries can cause visual disturbances, binocular system problems, and visual loss. About 25% of veterans exposed to blasts report corneal injury. Blast exposure induces corneal edema, corneal opacity, increased corneal thickness, damage of corneal epithelium, corneal abrasions, and stromal and endothelial abnormality including altered endothelial density, immune cell infiltration, corneal neovascularization, Descemet membrane rupture, and increased pain mediators in animal models and the blast-exposed military personnel including veterans. Immune response exacerbates blast-induced ocular injury. TBI is associated with dry eyes and pain in veterans. Subjects exposed to blasts that cause TBI should undergo immediate clinical visual and ocular examinations. Delayed visual care may lead to progressive vision loss, lengthening/impairing rehabilitation and ultimately may lead to permanent vision problems and blindness. Open-field blast exposure could induce corneal injuries and immune responses in the cornea. Further studies are warranted to understand corneal pathology after blast exposure. A review of current advancements in blast-induced corneal injury will help elucidate novel targets for potential therapeutic options. This review discusses the impact of blast exposure-associated corneal disorders.
Topics: Blast Injuries; Humans; Corneal Injuries; Animals; Cornea; Vision Disorders
PubMed: 38677709
DOI: 10.1016/j.exer.2024.109915 -
Arquivos Brasileiros de Oftalmologia 2024
Topics: Humans; Eye Injuries; Blast Injuries
PubMed: 38655939
DOI: 10.5935/0004-2749.2023-0322