Undersea and Hyperbaric Medicine最新文献

{"title":"A Non-Invasive Gas Exchange Monitor To Assess Swimming-Induced Pulmonary Edema.","authors":"Yousef Ahmed, Peter Lindholm, Nick Bartlett, Michael Tripp, Gil Boswell, Charles Volk","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Introduction: </strong>Swimming-induced pulmonary edema (SIPE) occurs in physically demanding environments. SIPE has been identified among U.S. Naval Special Warfare (NSW) candidates, risking trainees' lives or, less severely, preventing them from completing training. Diagnosis is based on clinical examination and chest X-ray. The MediPines gas exchange monitor AGM-100 is a noninvasive diagnostic tool approved by the FDA and used in hospital settings. This study aimed to assess noninvasive physiological parameters and evaluate the use of the AGM-100 in NSW candidates with SIPE.</p><p><strong>Methods: </strong>In this observational study, eighteen subjects were tested (nine with confirmed SIPE). Data on a noninvasive surrogate for oxygen deficit, based on end-tidal oxygen (EtO₂),carbon dioxide (EtCO₂), and SpO₂ were collected. Chest X-rays (CXR) were graded for interstitial and airspace edema.</p><p><strong>Results: </strong>Subjects with confirmed SIPE displayed an oxygen deficit (28.1 ± 12.9 mm Hg), while eight of nine subjects without SIPE did not (3.1 ± 8.79 mm Hg, p < 0.001). There were no differences in EtCO₂. SpO₂ was lower in individuals with confirmed SIPE (95.1 ± 2.23%) compared to controls/unconfirmed SIPE (98.1 ± 0.31%, p-value < 0.0001). The group with the oxygen deficit had a correspondingly worse edema grade on CXR.</p><p><strong>Discussion: </strong>These limited results showed a possible correlation between O₂ deficit and SIPE, while the AGM-100 performed reliably in this prehospital setting. Future higher-powered studies are needed to substantiate these findings and the AGM-100's utility, possibly extending to other environments, such as combat field hospitals, for rapid diagnosis and severity assessment of pulmonary edema.</p>","PeriodicalId":49396,"journal":{"name":"Undersea and Hyperbaric Medicine","volume":"53 2","pages":"343-348"},"PeriodicalIF":0.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148347036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Renal Effects of Acute Carbon Monoxide Poisoning: The Role of HIF-2α as a Biomarker of Tubular Injury.","authors":"Mehmet Tatli, Ismail Altintop, Cigdem Karakukcu, Zeynep Soyer Sarıca, Arzu Hanım Yay, Recep Özkan","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Introduction: </strong>Carbon monoxide (CO) poisoning is a serious public health concern that induces acute hypoxia, leading to organ damage. The effects of CO exposure on renal function remain insufficiently studied. This study aimed to investigate the impact of CO poisoning on kidney function and structure in an experimental rat model and to evaluate the role of hypoxia-inducible factor-2 alpha (HIF-2α) in this process.</p><p><strong>Methods: </strong>A total of 69 female Wistar Albino rats were used in the study. The rats were divided into a control group (n=9) and experimental groups exposed to CO poisoning and sacrificed at one hour (n=12), six hours (n=12), 12 hours (n=12), 24 hours (n=12), and 48 hours (n=12) post-exposure. CO exposure was administered at a concentration of 5000 ppm for 60 minutes. Blood gas analysis was performed, histopathological changes were evaluated using hematoxylin and eosin (H&E) staining, and HIF-2α expression was assessed via immunohistochemistry.</p><p><strong>Results: </strong>Significant histopathological changes were observed in kidney tissue following CO poisoning, including tubular degeneration, epithelial necrosis, and necrotic debris accumulation (p<0.001). Blood gas analysis showed a significantly elevated carboxyhemoglobin (COHb) level at one hour post-exposure (p<0.001), which returned to normal after six hours. Immunohistochemical analysis revealed a significant increase in HIF-2α expression following CO exposure (p<0.001), with a positive correlation between HIF-2α expression and tubular damage.</p><p><strong>Discussion: </strong>CO poisoning induces renal tubular injury and increases HIF-2α expression as a hypoxic response. These findings suggest that HIF-2α could serve as a potential biomarker for assessing renal damage due to CO exposure. Further studies are needed to evaluate the diagnostic and therapeutic implications of these findings in CO poisoning.</p>","PeriodicalId":49396,"journal":{"name":"Undersea and Hyperbaric Medicine","volume":"53 2","pages":"295-304"},"PeriodicalIF":0.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148346929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Case of Abdominal Pain Due to a Hemolytic Attack After Diving.","authors":"Yoichi Yanagawa, Soichiro Ota, Noriko Tanaka, Chihiro Maekawa, Hiroki Nagasawa","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Introduction: </strong>We hereby present a case of abdominal pain resulting from a hemolytic reaction after diving.</p><p><strong>Case report: </strong>The patient had preexisting hemolytic anemia triggered by cold stimuli. We hypothesize that the hemolysis was induced by cold stimuli during winter diving.</p><p><strong>Discussion: </strong>It is recommended that individuals with a preexisting hemolytic anemia refrain from diving.</p>","PeriodicalId":49396,"journal":{"name":"Undersea and Hyperbaric Medicine","volume":"53 2","pages":"333-336"},"PeriodicalIF":0.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148347083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Avascular Necrosis (Aseptic Osteonecrosis).","authors":"E M Camporesi, V Zanon, G Vezzani, G Bosco","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Avascular necrosis (AVN), also referred to as aseptic osteonecrosis (AO), can develop in several osseous districts of the body. Most commonly described is avascular necrosis of the femoral head (AVNFH), a debilitating and progressively disabling condition with partially understood, wide-ranging etiology and pathogenesis. Pathology is chiefly caused by a reduced vascularization of a terminal vascular bed, such as the one perfusing the femoral head, or similar vascular distributions such as femoral condyles, humeral head, the talus, the calcaneus, the navicularis, and other bony structures. Hypoxic conditions mediate the condition and can improve with a course of hyperbaric oxygen (HBO₂). The Ficat classification is one of the most widely used staging systems for AVN of the femoral head. It classifies patients with osteonecrosis into four stages based on the appearance on a plain radiograph, at least before the advent of MRI, the ultimate golden standard for the specific case. I- Pain but no radiographic anomalies II- Increased density, cystic changes, or porosity III- Flattening of the femoral head and crescent sign IV- Full collapse of the femoral head with decrease in joint space Many of the treatment options proposed aim to achieve joint preservation. However, when the radiological signs progress to advanced bone collapse in the articular capsule, the single mandatory surgery approach is a femoral head replacement with total hip arthroplasty (THA).</p>","PeriodicalId":49396,"journal":{"name":"Undersea and Hyperbaric Medicine","volume":"53 2","pages":"391-398"},"PeriodicalIF":0.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148347110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nitrofurantoin-Induced Hemolytic Anemia and Methemoglobinemia in G6PD Deficiency Treated With Hyperbaric Oxygen Treatment.","authors":"Vanraj Padhiyar, Abhishek Maitra, Chakit Singh, Neeraj Tulara","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Introduction: </strong>Methemoglobinemia is a rare but potentially serious condition characterized by an increased level of methemoglobin in the blood, which impairs oxygen delivery to tissues. It occurs when hemoglobin's ferrous iron (Fe²⁺) is oxidized to ferric iron (Fe³⁺), rendering it unable to bind oxygen effectively. This leads to tissue hypoxia, which can manifest clinically as cyanosis, shortness of breath, fatigue, and, in severe cases, organ dysfunction.</p><p><strong>Case report: </strong>Nitrofurantoin-induced hemolytic anemia and methemoglobinemia in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency are rare but potentially life-threatening complications. We present the case of a 64-year-old female with G6PD deficiency who developed acute hemolytic anemia and methemoglobinemia following nitrofurantoin therapy for a urinary tract infection. Her initial symptoms included fatigue, jaundice, and dyspnea, progressing rapidly to severe anemia and cyanosis. Laboratory investigations confirmed hemolysis and elevated methemoglobin levels. Although methemoglobinemia is commonly treated with methylene blue, its use in G6PD-deficient patients can exacerbate hemolysis. In this case, we promptly discontinued nitrofurantoin and managed the patient with hyperbaric oxygen treatment, intravenous ascorbic acid, and other supportive measures. Despite aggressive treatment, she required blood transfusion support and prolonged hospitalization.</p><p><strong>Discussion: </strong>This case underscores the importance of recognizing the potential for nitrofurantoin-induced hemolytic anemia and methemoglobinemia in G6PD-deficient individuals, highlighting the need for careful drug selection and vigilant monitoring in this population.</p>","PeriodicalId":49396,"journal":{"name":"Undersea and Hyperbaric Medicine","volume":"53 2","pages":"235-242"},"PeriodicalIF":0.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148347045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adjunctive Hyperbaric Oxygen in the Treatment of Thermal Burns.","authors":"Paul Cianci, Ronald M Sato, Julia Faulkner","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A significant and consistently positive body of evidence from animal and human studies of thermal injury supports the use of hyperbaric oxygen as a means of preventing dermal ischemia, reducing edema, modulating the zone of stasis, preventing partial- to full-thickness conversion, preserving cellular metabolism, dampening inflammation, preventing infection, and promoting healing. The overwhelming majority of clinical reports have shown reduced mortality, length of hospital stays, number of surgeries, and cost of care. Hyperbaric oxygen has been demonstrated to be safe in the hands of those thoroughly trained in rendering this therapy in the critical care setting and with appropriate monitoring precautions. Careful patient selection is mandatory.</p>","PeriodicalId":49396,"journal":{"name":"Undersea and Hyperbaric Medicine","volume":"53 2","pages":"363-390"},"PeriodicalIF":0.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148347076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recovery Patterns During Extended Hyperbaric Oxygen Treatment Combined With Steroids in Severe Sudden Sensorineural Hearing Loss: A Multi-Center Study.","authors":"Wen-Zhi Yang, Mei Yang, Tong Yang, Zhe Wang, Wan Lin, Shu-Yi Pan, Hang Li","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Introduction: </strong>Severe sudden sensorineural hearing loss (SSNHL) is a challenging otological emergency. Hyperbaric oxygen (HBO₂) treatment is an adjunctive treatment for SSNHL, improving oxygen supply and microcirculation and reducing oxidative stress. While HBO₂ is increasingly used for SSNHL, the temporal patterns of hearing recovery during extended treatment protocols remain poorly characterized. This study investigates the frequency-specific recovery patterns and speech recognition improvements during a 30-session HBO₂ protocol with concurrent steroid treatment in patients with severe SSNHL.</p><p><strong>Methods: </strong>This multi-center, retrospective cohort study included patients diagnosed with severe SSNHL at four medical centers from January 2019 to December 2024. Inclusion criteria included patients who initiated HBO₂ with steroids within five days of onset, completed 30 HBO₂ sessions, and underwent pure-tone audiometry and speech recognition assessments at specified intervals. A total of 103 patients receiving combined HBO₂ and steroid treatment were analyzed using SPSS.</p><p><strong>Results: </strong>Low-frequency hearing (125 Hz, 250 Hz, and 500 Hz) exhibited rapid recovery, with significant enhancements noted after ten sessions of HBO₂ (P < 0.05). In contrast, mid-frequency hearing (1000 Hz and 1500 Hz) and high-frequency hearing (2000 Hz) showed notable improvements after 20 and 30 sessions (P < 0.05), with the 30-session treatment resulting in greater enhancements compared to the 20-session treatment (P < 0.05). Speech recognition rates significantly improved after 20 and 30 sessions of HBO₂ compared to pre-treatment levels (P < 0.05), with the 30-session treatment showing statistically significantly higher rates than the ten-session HBO₂ (P < 0.05).</p><p><strong>Discussion: </strong>Hyperbaric oxygen treatment significantly enhances hearing and speech recognition in severe SSNHL, particularly in the mid-frequency range. Long-term HBO₂ treatment may be a viable option for these patients.</p>","PeriodicalId":49396,"journal":{"name":"Undersea and Hyperbaric Medicine","volume":"53 2","pages":"261-270"},"PeriodicalIF":0.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148346988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tension Pneumothorax During Hyperbaric Oxygen Therapy With Pigtail Pleural Catheter: A Case Report and Experimental Flow Analysis.","authors":"Gerald Schmitz","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Introduction: </strong>Tension pneumothorax is a life-threatening complication during hyperbaric oxygen treatment (HBO₂). The presence of a pleural catheter is assumed to mitigate this risk, but its efficiency under hyperbaric conditions remains unclear.</p><p><strong>Case report: </strong>We describe a 37-year-old female undergoing HBO₂ with a pigtail pleural catheter in situ for secondary pneumothorax. The patient developed respiratory and cardiovascular symptoms during decompression. To investigate gas flow dynamics, we conducted an experimental analysis measuring flow resistance in pigtail catheters under chamber pressures up to a chamber gauge pressure of 172.37 kPa. Flow rates were analyzed across a range of differential pressures and catheter fenestration numbers. Gas flow increased non-linearly with pressure but plateaued at higher differentials, indicating drainage limitations. Catheters with fewer fenestrations exhibited significantly reduced flow rates. Under simulated HBO₂ conditions, pressure differentials exceeding 2.4 kPa resulted in delayed gas evacuation, mirroring the clinical event.</p><p><strong>Discussion: </strong>This case and experimental study highlight the potential risk of inadequate pneumothorax drainage with pigtail catheters during HBO₂. We recommend decompression rates ≤1 psi/min to mitigate this risk. Further studies are needed to evaluate alternative catheter designs for hyperbaric environments.</p>","PeriodicalId":49396,"journal":{"name":"Undersea and Hyperbaric Medicine","volume":"53 2","pages":"255-260"},"PeriodicalIF":0.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148347048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbiological Contamination Risk in SCUBA Diving Cylinders: An Experimental Study.","authors":"Recep Özkan, Elif Okumuş, Kübra Özgök Kangal","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Introduction: </strong>The microbiological safety of compressed air in SCUBA diving cylinders is a crucial yet often overlooked aspect of diving safety. Despite regular maintenance, microbial contamination can cause respiratory illnesses, especially during the air-filling procedure. Given the impact of temperature increases on bacterial viability, this study evaluates the survival of Streptococcus pneumoniae (S. pneumoniae) and Pseudomonas aeruginosa (P. aeruginosa) within diving SCUBA cylinders during and after the air-filling process.</p><p><strong>Methods: </strong>A mixture of Streptococcus pneumoniae (ATCC 49619) and P. aeruginosa (ATCC 27853) was prepared using 25 ml of each bacterial strain at a 0.5 McFarland standard to contaminate the clean scuba cylinder. The mixture was poured into the cylinder to ensure full surface contact. The scuba cylinder was filled according to standard procedures, with temperature monitored at regular intervals using a precise thermometer. Measurements were repeated at increments of 10 bar until the cylinder reached 200 bar. After all air was released, 50 ml of sterile saline was poured into the cylinder to collect any remaining contamination. Swab samples were taken from the cylinder's gas outlet. Microbiological analysis was performed using filter, saline, and swab samples.</p><p><strong>Results: </strong>Growth of S. pneumoniae was observed on filters. Bacterial growth was detected on filters as follows: 1 CFU on the first filter, 3 CFU on the second, 2 CFU on the third, 2 CFU on the fourth, and 3 CFU on the fifth filter. Saline collected from the cylinder exhibited a bacterial count of 200 CFU/ml, with growth of S. pneumoniae detected. The swab sample taken from the gas inlet of the cylinder also revealed the presence of S. pneumoniae. However, no growth of P. aeruginosa was observed in any of the collected samples.</p><p><strong>Discussion: </strong>According to the results, S. pneumoniae can withstand the compressed air-filling process in diving cylinders, but P. aeruginosa cannot, possibly because of its increased sensitivity to pressure. Though no clinical cases of infection from cylinder air have been reported, these findings highlight how crucial it is to use additional sterilizing procedures in addition to temperature and pressure control to guarantee the microbiological safety of scuba diving equipment.</p>","PeriodicalId":49396,"journal":{"name":"Undersea and Hyperbaric Medicine","volume":"53 2","pages":"325-332"},"PeriodicalIF":0.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148347087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hyperbaric Oxygen Treatment Attenuates Renal Ischemia/Reperfusion Injury in Rats.","authors":"Bo Yang, Jun Liu, Lingling Ding, Maoting Li, Xuezi Fu, Zhe Li, Jin Cheng, Nanmei Liu","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Introduction: </strong>Acute Kidney Injury (AKI) is a critical condition with high morbidity and mortality, often caused by ischemia-reperfusion (I/R) injury. Hyperbaric oxygen treatment (HBO₂) enhances tissue oxygenation and has shown potential in hypoxic conditions. This study evaluated the efficacy of HBO₂ in mitigating renal I/R injury in a rat model.</p><p><strong>Methods: </strong>Sprague-Dawley rats were divided into three groups: Control (sham surgery, n = 9), I/R (n = 9), and I/R +HBO (n = 9). I/R was induced by 30-minute bilateral renal pedicle occlusion followed by reperfusion. The I/R +HBO group received two sessions of HBO₂ (90 min at 1.6 ATA) at two and 22 hours post-reperfusion. Renal function was assessed via serum creatinine and blood urea nitrogen (BUN) levels. Histopathological and molecular analyses examined tissue damage, inflammation, and necroptosis markers (p-RIP3/pMLKL).</p><p><strong>Results: </strong>The I/R group showed significantly elevated BUN and creatinine levels compared to the Control (p < 0.05). HBO₂ significantly reduced these levels compared to the I/R group. Histopathology revealed severe tubular damage and neutrophil infiltration in I/R rats, while HBO₂ improved renal structure and decreased necroptosis activation.</p><p><strong>Discussion: </strong>HBO₂ effectively reduced renal I/R injury by mitigating inflammation, oxidative stress, and necroptosis. These findings suggest HBO₂ as a potential therapeutic strategy for AKI, warranting further clinical investigation.</p>","PeriodicalId":49396,"journal":{"name":"Undersea and Hyperbaric Medicine","volume":"53 2","pages":"279-290"},"PeriodicalIF":0.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148347041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}