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ABSTRACT Doğan M, Atan Y, Dağ MA, Üzün İ. Multifactorial Determinants of Diving-Associated Deaths in Turkey: Autopsy-Based Insights and the Imperative of Integrated Forensic Assessment. Undersea Hyperb Med. 2026 First Quarter; 53(1):1-14. Introduction: This autopsy-based study aims to investigate the underlying causes and forensic characteristics of fatal diving incidents in Turkey, emphasizing the autopsy-based strategies employed to distinguish drowning from other diving-related pathologies such as decompression illness and arterial gas embolism. Methods: A retrospective analysis was conducted on 11 fatal diving cases evaluated by the First Forensic Medicine Specialization Board between 2002 and 2023. Data were retrieved from judicial records, including detailed autopsy reports, histopathological findings, toxicological analyses, and scene investigations. Results: The decedents consisted of ten males and one female (median age: 45), reflecting the male- dominant profile of diving activity. Diving modalities included SCUBA (n=7), breath-hold (n=2), and surface-supplied compressor diving (n=2). The leading cause of death was drowning (n=5), followed by arterial gas embolism (AGE; n=2), sudden cardiac death (n=2), subarachnoid hemorrhage (n=1), and asphyxia due to mechanical entrapment (n=1). AGE cases demonstrated intravascular gas via specialized autopsy techniques. Cardiovascular comorbidities were identified in four cases, while medications— primarily prescribed—were detected in five. Alcohol and illicit drugs were absent in all cases. Discussion: Diving fatalities pose complex medicolegal challenges that require a multidisciplinary approach. Drowning and AGE were the most ..

ABSTRACT Wolkowski U, Khatib S, Arieli R. The amount of the settled surfactant dipalmitoylphosphatidylcholine (DPPC) in the heart of rats does not correlate with decompression illness Undersea Hyperb Med. 2026 First Quarter; 53(1):15-18. Introduction: The lung surfactant dipalmitoylphosphatidylcholine (DPPC) settles on the luminal aspect of blood vessels to form active hydrophobic spots (AHS). The nanobubbles that develop at these spots are gas micronuclei from which decompression bubbles expand upon decompression. Variability between “bubblers” and “non-bubblers” is derived from the variability in the AHS. We expected that the level of DPPC in the heart would correlate with the severity of decompression illness (DCI). Methods: Thirty-six rats were exposed to 8 bar for 32 minutes. Results: After decompression, they were examined for DCI and defined as non-DCI rats (ND, n=18), DCI- inflicted rats (DCI, n=13), and dead rats (DEATH, n=5). The DPPC concentration in the hearts (mg/g) was 2.97 ± 0.56 SD for ND, 2.87 ± 0.62 SD for DCI, and 2.81 ± 0.46 SD for DEATH. Discussion: There was no significant difference between the three groups. The results are discussed, and a further study to explore the correlation between bubbling and heart DPPC is suggested. Keywords: bubbles; decompression illness; diving; diving research; hyperbaric research DOI: 10.22462/893

ABSTRACT Sjöblom C, Ekman L, Plogmark O, Mandić M, Rodríguez-Zamora L, Melin AK, Ekström M, Frånberg O. Maximal fat oxidation in navy divers. Undersea Hyperb Med. 2026 First Quarter; 53(1):19-30. Introduction: Oxidating fat as an energy substrate requires more oxygen than utilizing carbohydrates and can be acutely increased by hyperoxia. Therefore, substrate utilization may affect endurance performance and gas consumption in divers, but previous research is limited. This study aimed to evaluate changes in maximal fat oxidation (MFO) in navy divers during training. Methods: Seven explosive ordnance disposal (EOD) divers (age 20.0±1.4, BMI 23.5±1.6), five combat divers (age 23.6±3.0, BMI 26.2±1.2), and seven amphibious rangers (controls) (age 23.0±2.9, BMI 26.2±1.7) were recruited. MFO was measured with indirect calorimetry using an incremental test before and after diver training of 15 weeks (EOD divers) or 16 weeks spaced over nine months (combat divers and controls). EOD divers performed a treadmill protocol in normoxia and hyperoxia, and combat divers and controls performed a bicycle ergometer protocol in normoxia. Results: Combat divers increased their MFO with 0.14 g/minute ([95 % CI] 0.04 to 0.23) while no difference was observed in EOD divers (-0.05 g/minute; -0.19 to 0.08) or controls (0.00 g/minute; -0.14 to 0.14). Discussion: Combat diver training can increase fat oxidation, potentially affecting oxygen consumption and carbon dioxide production. A combination of training ..

ABSTRACT Özkan R, Kaya B. High-Altitude Decompression Illness Following Recreational Diving: A Case Report from Lake Van. Undersea Hyperb Med. 2026 First Quarter; 53(1):31-34. Rationale: Decompression sickness (DCS) is a clinical syndrome caused by inert gas bubble formation following a rapid reduction in ambient pressure, with an increased risk in high-altitude diving due to lower barometric pressure. Although neurological symptoms are well-documented, respiratory involvement is less frequently reported. Patient Presentation: A 54-year-old male recreational diver performed his first-ever dive in Lake Van, descending to approximately 30 meters and remaining at depth for several minutes before ascending rapidly to the surface without a decompression stop. Immediately after surfacing, he experienced sudden weakness in both legs and shortness of breath. He aspirated water and recalled calling for help before losing awareness. Located approximately 300 meters from shore, he was towed back by his dive team. Finding no pulse, the team initiated CPR and rescue breathing. Upon arrival, emergency medical services found the patient with spontaneous respiration and a palpable pulse. Within 30 minutes, he was transported approximately 16 kilometers to the nearest hospital. High- flow oxygen treatment via a non-rebreather mask was initiated, and he was transferred to the emergency department. In the emergency department, the patient stated he remembered seeing lights but could not recall the intervening events. Due to ..

ABSTRACT Miyoshi Y, Watanabe S, Tsukazaki S, Sugiura T, Ikomi F, Tanaka T, Ogawa H, Sawamura T. Risk Factors of Dysbaric Osteonecrosis in Saturation Diving Identified through Magnetic Resonance Imaging Surveillance. Undersea Hyperb Med. 2026 First Quarter; 53(1):35-46. Introduction: Only a few cohort studies have investigated dysbaric osteonecrosis (DON) in saturation diving (SD) divers using magnetic resonance imaging (MRI) to detect early-stage DON. We aimed to investigate DON in the Japan Maritime Self-Defense Force (JMSDF) deep SD divers using MRI and examined the relationship between DON and the risk factors. Methods: This study included 62 JMSDF SD divers. DON was diagnosed in the subjects’ shoulders, hips, and knee joints using MRI and their clinical information. We analyzed subjects’ diving records, including pre- and post-diving medical check information such as decompression sickness (DCS) and pain +/–. Data from the annual JMSDF health checks were analyzed to identify risk factors for DON based on divers’ predispositions, lifestyles, and diving profiles. Results: Of the 62 saturation divers (mean age: 40.61±6.93 years), three (4.8%) showed evidence of DON. MRI showed a geographic lesion with symptoms or a history of DCS. Two divers with DON had knee pain and a history of DCS. Furthermore, one asymptomatic diver and another diver with pain were heavy drinkers. Regarding physical and biochemical examination, diastolic blood pressure ..

ABSTRACT Özkan R, Kaya B, Kaya G. Vascular occlusion following hyaluronic acid injection: A case report. Undersea Hyperb Med. 2026 First Quarter; 53(1):47-50. Introduction: This case presentation discusses vascular occlusion following hyaluronic acid (HA) injection and the subsequent treatment. Case Report: A 52-year-old female underwent a 0.2 ml HA filler injection for aesthetic purposes in the forehead area, followed by the development of discoloration and severe pain extending from the glabellar region to the forehead. Discussion: The diagnosis was determined as vascular occlusion due to the injection, and the patient received 300 IU of hyaluronidase immediately. Additionally, hyperbaric oxygen treatment (HBO2) was initiated. The patient received seven HBO2 treatments and healed without developing post-treatment necrosis. No scar formation was observed at the three-month follow-up. This case highlights the potential benefits of HBO2 in managing complications arising from HA fillers. It underscores the importance of physicians performing aesthetic procedures, being attentive to facial anatomy and injection techniques to prevent such complications. Furthermore, having knowledge about the effectiveness of HBO2 in potential complication scenarios and collaboration with hyperbaric clinics when necessary are recommended. Keywords: Filler complications; hyaluronidase hyperbaric oxygen treatment; hyaluronic acid; intra-arterial injection DOI: 10.22462/838

ABSTRACT Thacker J, Pullis M, Masters T, Logue C. Laptop-style point-of-care ultrasound machines in the multiplace hyperbaric oxygen treatment chamber. Undersea Hyperb Med. 2026 First Quarter; 53(1):51-58. Introduction: Point-of-care ultrasound (POCUS) has diverse uses in the critical care hyperbaric (HBO2) environment. The use of electronic devices in a multiplace HBO2 chamber has traditionally been limited secondary to fire risk. Methods: The primary outcome was to assess the feasibility of modern laptop-style POCUS machines in a multiplace HBO2 chamber. A secondary aim was to assess the reliability of POCUS images obtained at different pressures in a human subject in a multiplace chamber. Testing was initially conducted with one older machine (Sonosite 180 and Sonosite Micromaxx). Subsequently, two newer machines were studied (Sonosite Edge II and Mindray M9). Machine and transducer reliability were tested by performing a battery of POCUS imaging sequences: cardiac, FAST, inferior vena cava, and thoracic. The POCUS cardiac sequences evaluated included 2D, color Doppler, and M-mode. Results: Regarding feasibility, all machines functioned well at all depths/pressures. No instances of fire or spark were observed. No surface temperatures above 1200F were recorded. Regarding reliability, all machines performed adequately and completed the entire imaging sequence. Discussion: This study demonstrates the HBO2 chamber safety of four laptop-style POCUS machines: Sonosite 180, Sonosite Micromaxx, Sonosite Edge II, and the Mindray M9. Our results also demonstrate excellent functionality ..

ABSTRACT Hurlburt S, Orwig D. Registered Nurses in Hyperbaric Medicine: Increasing Patient Compliance with Hyperbaric Oxygen Therapy. Undersea Hyperb Med. 2026 First Quarter; 53(1):59-64. Introduction: A quantitative analysis explored whether adding a full-time registered nurse (RN) and implementing nurse-led education and follow-up within the hyperbaric department affects patient treatment compliance and daily attendance rates. Methods: Data from two seven-month periods of hyperbaric appointments were retrospectively reviewed. Period One consists of canceled appointments from January to July 2023, when there was no dedicated nursing role in the department. Period 2 consists of canceled appointments from January to July 2024, following the addition of a full-time RN to the staffing matrix and the integration of nurse-led education into the department’s workflow. Results: A chi-square test of the data showed a significant association (p < 0.001) between the addition of a full-time RN, nurse-led education, and follow-ups, and the number of canceled hyperbaric appointments. The estimated risk of cancellation prior to the interventions was 0.11, 11% higher than the rate after a dedicated nursing role was implemented (p-value < 0.001 and 95% CI for the proportion difference (0.087-0.13)). The odds of patients canceling hyperbaric appointments are 107% higher in departments without a dedicated RN role (p < 0.001). The OR=2.07, 95% CI (1.78 – 2.4). Discussion: After reviewing attendance data across two ..

ABSTRACT Jusoh AF, Ismail I, Yahaya R, Hassan A, Yusoff HM. Hyperbaric Oxygen Therapy in Traumatic Brain Injury: A Comprehensive Structure Review. Undersea Hyperb Med. 2026 First Quarter; 53(1):65-82. Introduction: Hyperbaric oxygen (HBO2) treatment has sparked increasing attention as a potential therapeutic intervention for traumatic brain injury (TBI), but the variability in findings necessitates a comprehensive analysis of recent literature. This review aims to evaluate the latest empirical evidence on the effectiveness of HBO2 treatment for TBI, focusing on its impact on neurological recovery, cognitive function, and physiological markers. Methods: To achieve this, we extensively searched scholarly articles in reputable databases such as Scopus and Web of Science (WoS), focusing on studies published between 2015 and 2024, and followed the PRISMA framework for study selection. The final dataset comprised 74 cases (n=74) and was analyzed using both quantitative methods (descriptive statistics) and qualitative techniques (thematic analysis). The findings were divided into three themes: (1) clinical efficacy of HBO2 treatment for TBI, (2) mechanisms of action and biological pathways in HBO2 treatment, and (3) evolving therapeutic applications of HBO2 in TBI. Results: Mixed outcomes; while some studies reported significant cognitive, physiological, and clinical improvements, others raised concerns about methodological variability and limited reproducibility. Mechanistic studies highlighted HBO2's role in modulating pathways such as TLR4/NF-κB and VEGF/ERK, facilitating neuroprotection, angiogenesis, and synaptogenesis. Emerging therapies combining HBO2 with ..

ABSTRACT Amamri A, Miliani A, Boudour R, Mellal Y, Dib M, Medaouar, Bedjaoui A. Dysbaric osteonecrosis: Case series osteonecrosis in divers. Undersea Hyperb Med. 2026 First Quarter; 53(1):83-89. Introduction: This is the first published study examining decompression illness (DCI) among divers in Algeria. DCI is a complex syndrome caused by bubbles of inert gas that form in the body due to an improper decompression process, following exposure to increased pressure underwater. Algerian diving conditions pose significant challenges to divers. The study focuses on red coral diving, a popular and long-standing practice in eastern Algeria. We present three case reports describing dysbaric osteonecrosis of the humeral head with varying degrees of severity and presentation. Dysbaric osteonecrosis (DON), a rare complication in professional divers and compressed-air workers, presents a controversial link to previous decompression sickness (DCS) with musculoskeletal pain (type 1 DCS). The potential for these ischemic lesions to progress to osteonecrosis after DCS remains unclear. Case Report: This report describes a professional diver declared permanently unfit for diving due to advanced dysbaric osteonecrosis of the shoulder, following type 1 DCS in the same region treated with hyperbaric oxygen therapy. This case highlights the potential association between these events and emphasizes the importance of close monitoring after acute type 1 DCS. Discussion: Early magnetic resonance imaging (MRI) evaluation of all ..

ABSTRACT Schmitz G, Aguero S, Huertas Gabert LC. Case of Broca's Aphasia as an expression of cerebral decompression sickness with advanced non-invasive monitoring during HBO2 treatment. Undersea Hyperb Med. 2026 First Quarter; 53(1):91-97. Introduction: We present a case of severe CNS decompression sickness (DCS) that included Broca’s aphasia in a recreational diver, offering insights into the application of advanced non-invasive monitoring during hyperbaric oxygen treatment (HBO2). Case Report: This 64-year-old male diver experienced the onset of expressive aphasia, vertigo, and right- sided hemiparesis about 30-120 minutes after surfacing following a rapid ascent after a deep dive. Discussion: Initial monitoring with bispectral index (BIS) and density spectral array (DSA) revealed significant asymmetry between cerebral hemispheres, particularly in spectral edge frequency (SEF) values, with the left hemisphere showing a marked reduction during air breaks at HBO2 pressures. This pattern resolved progressively over three HBO2 sessions, with full clinical recovery after four sessions, coinciding with the resolution of this DSA hemispheric asymmetry. The case indirectly supports the theoretical roles of microparticles and endothelial dysfunction in contributing to cerebral hypoperfusion in DCS, beyond the conventional focus on gas bubbles, as reflected in the clinical findings and the clinical gradient. This novel application of BIS-DSA in hyperbaric medicine offers promising potential for real- time monitoring of cerebral involvement. It could enhance patient outcomes by guiding individualized treatment in ..

ABSTRACT Kayacık SN, Gümüş Selek FZ, Aslan A, Karabakan R, Kıratlı Ü. Hyperbaric Oxygen Therapy in Stroke- Related Sudden Hearing Loss: A Case Report. Undersea Hyperb Med. 2026 First Quarter; 53(1):99- 104. Introduction: Sudden sensorineural hearing loss (SSNHL) refers to a rapid decline in hearing of 30 dB or more that develops within three days, impacting at least three consecutive frequencies in one or both ears. Case Report: This case report examines the improvement in hearing levels through hyperbaric oxygen treatment in a 74-year-old male patient who developed sudden hearing loss following a stroke. Discussion: After 15 days of neurological treatment, an audiological assessment revealed a 70 dB hearing loss in air conduction in the left ear. The patient initially received intravenous methylprednisolone for ten days, followed by five intratympanic steroid injections. Despite these treatments, no significant improvement in hearing was noted. The patient subsequently received 14 sessions of hyperbaric oxygen treatment, significantly improving hearing function. Keywords: Hyperbaric oxygen; sudden sensorineural hearing loss; stroke. DOI: 10.22462/829

ABSTRACT Fischer GA, Hangan D, Li JG, Saxe B, Christiansen C, Paticoff K, Richman O, Sasson H. Case report of auricular avulsion injury, repair, and adjunctive treatment. Undersea Hyperb Med. 2026 First Quarter; 53(1):105-109. Introduction: The objective of this case report is to present an 11-year-old male patient who sustained a partial avulsion injury of the left ear involving the helix, anti-helix, and scapha, along with initial management and adjunctive treatments throughout the patient’s course in the hospital. Case Report: Traumatic ear avulsion is an uncommon injury that poses unique surgical challenges, as there is no standard of care for its management. The viability of the avulsed tissue is of paramount concern given its small vasculature and limited perfusion. Some techniques used in ear avulsion injuries include microvascular reconstruction, the pocket technique, and direct reattachment. Ear avulsion injuries require a multidisciplinary approach to achieve optimal patient outcomes. Discussion: This case report demonstrates the effectiveness of multiple adjunctive treatments in optimizing revascularization and viability of previously avulsed tissue, resulting in better short-term outcomes and a more favorable long-term prognosis. Keywords: Hyperbaric oxygen treatment; leech therapy; trauma; wounds DOI: 10.22462/823

ABSTRACT Huang ET, Heyboer III M, Savaser DJ. Hyperbaric Oxygen Therapy for Selected Problem Wounds. Undersea Hyperb Med. 2025 First Quarter; 52(1):111-154. The field of Undersea and Hyperbaric Medicine has been segregated into those indications related to undersea medicine and those related to wound healing. Historically, though, hyperbaric medicine’s role in wound healing owes a debt to Jacques Cousteau’s divers working 35 feet under the surface of the Red Sea who claimed that their wounds healed significantly better when living in an underwater habitat than when they lived on dry land. In 1964, Dr. TK Hunt was asked by the National Science Foundation (NSF) to investigate these divers’ claims. Dr. Hunt’s work, along with that of his peers and colleagues, provide the scientific evidence and rationale that wound healing is dependent on tissue oxygenation [1].

ABSTRACT Feldmeier JJ, Gesell LB. Delayed Radiation Injuries (Soft Tissue and Bony Necrosis) and Potential for Future Research. Undersea Hyperb Med. 2026 First Quarter; 53(1):155-198. The application of hyperbaric oxygen (HBO2) to the treatment and prevention of late radiation injury (LRTI) is the focus for this chapter. Additional miscellaneous topics related to radiation exposure and HBO2 will also be explored, including areas of interest for research. We will also discuss some of the pertinent literature demonstrating the safety of HBO2 for the cancer patient. A review of billing records from CMS demonstrates that delayed radiation injuries continue to be the most frequent indication for hyperbaric treatments in the United States, constituting about 40% of all their billings [1]. Hyperbaric oxygen should not be the sole treatment modality for many cases of radiation injury. The management of delayed radiation injury, especially when bone is involved, will likely require a multi-disciplinary approach. Importantly, each aspect of treatment including surgical technique must be optimized to give the best chance for a successful therapeutic effort. For radiation injuries, surgical intervention may require tissue flaps and skin grafts to compensate for tissues lost due to frank necrosis or previous cancer surgery. Free flap procedures employing microsurgical vascular anastomoses are being employed more and more often when done in radiated fields. ..

ABSTRACT Van Meter KW. Severe Anemia. Undersea Hyperb Med. 2026 First Quarter; 53(1):199-208. Hyperbaric oxygen (HBO2) therapy serves as a critical bridge treatment for severe anemia when red blood cell transfusion is not possible due to religious objection, crossmatch incompatibility, or blood unavailability. Hemoglobin levels below 3.6 g/dL are clearly inadequate for tissue oxygenation, and accumulative oxygen debt exceeding 33 L/m2 within four hours of severe hemorrhage is unsurvivable. HBO2 administered at pressures of 2 to 3 ATA dissolves sufficient oxygen directly in plasma to compensate for the deficit in hemoglobin-bound oxygen-carrying capacity, while concurrent use of hematinics and erythropoietin-stimulating strategies supports endogenous red blood cell regeneration during surface intervals between treatments. Controlled animal studies spanning from 1943 through the 1990s consistently demonstrate improved survival in HBO2-treated groups compared to normobaric air controls across multiple hemorrhagic shock models; human case reports, case series, and one controlled prospective trial in post-hepatectomy patients further support clinical efficacy. Classified as an AHA Class IIb indication with long-standing CMS approval, HBO2 carries a cost comparable to a single unit of packed red blood cells and maintains a favorable safety profile with few and infrequent side effects. These findings position HBO2 as a practical, low-technology, cost-competitive intervention for reducing accumulated oxygen debt in critically anemic patients across settings including emergency departments, operative units, and intensive ..