Undersea and Hyperbaric Medicine最新文献

Introduction: When administering HBO₂ , pressures can range from 1.4 atmospheres absolute (ATA) to 3 ATA. While different treatment profiles have been proposed, there is a paucity of literature comparing the effectiveness and risk profile associated with different pressures treating the same condition. Considering the therapeutic divergence, this study aims to survey Undersea and Hyperbaric Medical Society (UHMS) members on pressure modalities and their use in different clinical conditions.

Methods: The study was a voluntary cross-sectional survey administered online and open to healthcare providers who were Undersea and Hyperbaric Medical Society members. UHMS itself distributed the survey link. The survey period lasted from November 2022 until January 2023. Data were collected utilizing the Qualtrics platform and analyzed through Microsoft Excel.

Results: A total of 265 responses were recorded. The majority responded with utilizing 2.4 ATA (35.2%) as the pressure of choice, followed by 2.0 ATA only (27.1%), and those who utilized differing therapeutic pressures (26.4%). The overwhelming choice for treatment of osteoradionecrosis (ORN) of the jaw, radiation proctitis/cystitis, diabetic foot ulcer, and chronic osteomyelitis was 2.0 ATA (68.0- 74.9%). Among listed adverse effects, myopia was the most commonly reported complication at 24.4%, followed by barotrauma (14.9%) and confinement anxiety (11.5%).

Conclusions: There is currently little consensus regarding the best treatment modalities for conditions treated with HBO₂. As adverse effects appear non-negligible, future prospective studies must be conducted weighing the risks and benefits of higher-pressure therapies compared to safer lower-pressure options.

Middle ear barotrauma (MEBT) is the most common complication in providing hyperbaric oxygen therapy (HBO₂). This study explored the impact of altering the shape of the time-pressure curve with the aim of reducing the occurrence of MEBT and optimizing the HBO₂ experience during the pressurization process. Four distinct mathematically derived protocols-Constant Pressure Difference (CPD), Constant Volume Difference (CVD), Constant Ratio (CR), and Inverted Constant Ratio (ICR)-were investigated using computer simulations on a simple ear model. Results indicated varying levels of ear strain during pressurization. The CR pressurization demonstrated balanced ear strain levels and outperformed other modalities in several measures, including the impact on the simulated ear cavity volume. The potential for enhanced patient comfort through the application of sophisticated pressurization protocols warrants further research to validate and extend the findings of this study in real-world HBO₂ settings.

Background: Hyperbaric Oxygen Therapy (HBO₂) is a treatment modality that exposes patients to 100% oxygen at higher atmospheric pressures. Recently, HBO₂ has emerged as a potential therapeutic option for various liver diseases, offering advantages such as improved tissue oxygenation, anti-inflammatory effects, enhanced wound healing, and potential hepatoprotective properties. Understanding the benefits of HBO₂ in liver diseases can pave the way for novel therapeutic strategies and improved patient outcomes. This study aimed to investigate the hepatoprotective effect of HBO₂ in arthritic rats treated with leflunomide (LEF) through anti-inflammatory and antioxidant pathways.

Material and methods: 24 male Sprague-Dawley rats were divided into three groups (8 animals in each group (n = 8)). 1^st group was the control group, which received no treatment. 2^nd group was RA + LEF 5 mg/kg, 3^rd group was RA + LEF 5 mg/kg + HBO₂. Rheumatoid arthritis was induced using Complete Freund's Adjuvant (CFA). The treatment was initiated on the 10^th day following induction and lasted for a total of 18 days. The impact on disease progression was assessed through histological changes, which were evaluated using hematoxylin-eosin staining, while the Anti-TNF-α antibody levels were determined.

Results: TCompared with the RL group, the RLH group significantly decreases necrotic cells, Lymphocyte- rich mononuclear cells, and active anti-TNF-α .

Conclusion: HBO₂ showed a beneficial effect and decreased hepatotoxicity on Leflunomide-induced liver injury.

Decompression after diving may inevitably cause the production of bubbles in the body, even without protocol violation. Bubbles produced in the circulation may damage the vascular cells, leading to vascular dysfunction. In this study, five subjects were recruited and subjected to hyperbaric exposure (15 meters; 100 minutes). The function of the brachial artery was assessed by measuring diameter, systolic peak velocity (SPV), resistance index (RI), and flow-mediated dilation (FMD) of the brachial artery before and after hyperbaric exposure. Our results showed that hyperbaric air exposure slightly increased the diameter of the brachial artery and significantly increased its RI but reduced the FMD and markedly decreased the SPV. This study indicates that hyperbaric air exposure at low pressure may also alter the function of the brachial artery.

Sudden sensorineural hearing loss (SSNHL) presents as the abrupt onset of hearing loss. Approximately 88% of SSNHL has no identifiable etiology and is termed idiopathic sudden sensorineural hearing loss (ISSHL). Hearing specialists have investigated ISSHL since the 1970s. Over the past 30 years, more than 800 articles, or one every two weeks, have been published in the English medical literature. ISSHL is the abrupt onset of hearing loss, usually unilaterally and upon wakening, that involves a hearing loss of at least 30 decibels (dB) occurring within three days over at least three contiguous frequencies. As most patients do not present with premorbid audiograms, the degree of hearing loss is usually defined by the presentation thresholds of the unaffected ear. Other associated symptoms include tinnitus, aural fullness, dizziness and vertigo. The historical incidence of ISSHL ranges from 5-20 cases/100,000 population, with approximately 4,000 new cases per annum in the United States. The true incidence is thought to be higher, as ISSHL is thought to be underreported. Interestingly, 4,000 cases annually calculate to 1.3 cases/ 100,000 in the United States; therefore, an incidence of 5-20/100,000 would translate to > 15,000 new ISSHL cases per annum in the United States. Recent literature has placed the annual ISSHL incidence in the United States as 27 cases/100,000, with a pediatric incidence of 11 cases/100,000. Other studies report that the incidence is increasing (160/100,000), especially in the elderly (77/100,000), and conclude that ISSHL is no longer rare. In 1984, Byl reviewed the literature and found the mean age of ISSHL presentation to be 46-49 years, with variation of incidence with age and an equal gender distribution. The presentation of ISSHL does not appear to have seasonal variations, uneven distributions of presentation throughout the year, or an association with upper respiratory infections, either prior to or following symptom onset. The spontaneous recovery is currently thought to be 30-60%.

Introduction: Arterial vascular occlusion is a rare complication of dermal filler injection. This case report describes the successful use of hyperbaric oxygen therapy in a patient with vascular occlusion after a permanent dermal filler was injected.

Case report: A 51-year-old woman underwent an injection of non-resorbable polymethylmethacrylate microspheres into her nasolabial folds. Several hours later, she experienced dusky discoloration of the right nasolabial fold and surrounding livedo skin changes, consistent with vascular occlusion. Treatment with warm compresses and topical nitroglycerin was initiated, and the patient was referred for hyperbaric oxygen therapy. The tissue discoloration improved significantly after the administration of six hyperbaric treatments.

Discussion: While hyaluronidase is recognized as a treatment option for vascular occlusion associated with using temporary fillers containing hyaluronic acid, it may also be beneficial for patients who experience vascular occlusion after administration of permanent fillers. Hyperbaric oxygen therapy, which results in hyperoxygenation of ischemic tissue and mitigation of the associated inflammatory response, may also benefit patients who experience vascular occlusion after permanent filler injection.

Conclusions: Administration of hyaluronidase and hyperbaric oxygenation should be considered for patients who develop arterial occlusions after dermal filler placement, regardless of the type of injected filler.

This report details a case study of a non-smoking 33-year-old female nurse who developed occupational asthma as an Inside Attendant (IA) in a hyperbaric chamber. The report analyzes the nurse's medical history, working environment, and potential causes. After beginning work in the hyperbaric chamber, an IA experienced respiratory symptoms, including coughing, wheezing, and fatigue. Her symptoms improved during a break attending a hyperbaric nursing certification program but returned when she resumed work in the IA hyperbaric chamber. Spirometry confirmed airflow obstruction, and the IA was subsequently diagnosed with occupational asthma. As a result, the IA had to terminate their employment in the hyperbaric chamber. The literature review indicates that diving and hyperbaric exposure can negatively affect respiratory function, particularly in individuals susceptible to respiratory issues. We emphasize the necessity for further research on the effects of hyperbaric exposure on the respiratory system of IAs.

Arieli has previously demonstrated that the exposure metric K could be used to predict pulmonary oxygen toxicity (POT) based on changes in Vital Capacity (VC). Our previous findings indicate that the Equivalent Surface Oxygen Time (ESOT) allows the estimation of POT without loss of accuracy compared to K. In this work, we have further investigated POT recovery. The K metric assumes that the recovery of POT is to be controlled by exposure to pO₂. This results in a counterintuitively slow estimated recovery after exposure to low pO₂. Similarly, K overestimates POT during intermittent hyperoxic exposures. We used results from previous studies to train the parameters of a new ESOT recovery model. The predicted recovery of ESOT (ESOT_rec) after initial hyperoxic exposure (ESOT_I) of duration t_exp (h) and recovery time t (h) can be calculated as ESOT_rec=ESOT_I · e^-f with f=0.439 · t · 0.906^t_exp. For intermittent exposures, the function ESOT(n)=(n · a · ln(b · n+1)+c) · t_exp · pO₂^2.285 will approximate POT (ESOT(n)) after n sessions of pO₂ (atm) for time t_exp (min) in each cycle. Parameters a, b, and c are specific for each cycling pattern. These ESOT functions will better predict the development of POT during intermittent hyperoxic exposures as well as recovery after a broader range of continuous hyperoxic exposures than K. We recommend limiting hyperoxic exposures in surface-oriented diving to ESOT=660, 500, and 450 for a maximum of one, five, and seven consecutive days, respectively. A minimum of 48 hours of recovery should follow. These limits can probably be relaxed for intermittent exposures.

Objective: To determine the outcomes of patients receiving hyperbaric oxygen therapy for sudden sensorineural hearing loss and the impact of patient comorbidities on outcomes.

Study design: Retrospective chart review.

Setting: Tertiary referral center.

Methods: All patients over 18 diagnosed with sudden sensorineural hearing loss between 2018 and 2021 who were treated with hyperbaric oxygen therapy were included. Demographic information, treatment regimens and duration, and audiometric and speech perception outcomes were recorded and analyzed.

Results: 19 patients were included. The median age was 45 years. 53% were female and 21% had pre- existing rheumatologic disorders. The mean duration between hearing loss onset and physician visits was 9.6 days. All patients received an oral steroid course, while 95% also received a median of 3 intratympanic steroid injections. Patients began hyperbaric oxygen therapy an average of 34.2 days after the hearing loss onset for an average of 13 sessions. No significant relationships were found between patient comorbidities and outcomes. Of those who reported clinical improvement, 57% demonstrated complete recovery per Siegel's criteria. There was significant improvement after hyperbaric oxygen therapy for pure tone averages (50.3dB vs. 36.0dB, p<0.01) and word discrimination scores (73% vs 79%, p<0.05) for all patients regardless of reported clinical improvement.

Conclusion: Hyperbaric oxygen therapy, as an adjunct to steroids, significantly improves recovery from sudden sensorineural hearing loss. The Charlson comorbidity index was not significantly associated with patient outcome, but patients with rheumatologic disorders were less likely to respond. Differentiating the natural history of the disease from hyperbaric oxygen therapy-associated improvements remains a challenge.

The term "intracranial abscess" (ICA) includes cerebral abscess, subdural empyema, and epidural empyema, which share many diagnostic and therapeutic similarities and, frequently, very similar etiologies. Infection may occur and spread from a contiguous infection such as sinusitis, otitis, mastoiditis, or dental infection; hematogenous seeding; or cranial trauma. Brain abscess usually results from predisposing factors such as HIV infection, immunosuppressive drug treatment, surgery, adjacent infection (i.e., mastoiditis, sinusitis, dental infection), or systemic infection causing bacteremia. Approximately 30% to 50% of infections are caused by contiguous spread of local infections. Hematogenous spread is responsible in around a third of cases, with the mechanism for the remainder not identifiable.