Undersea and Hyperbaric Medicine最新文献

Objective: To analyze Hyperbaric Oxygen Therapy Registry (HBOTR) data to estimate the Medicare costs of hyperbaric oxygen therapy (HBO₂) based on standard treatment protocols and the annual mean number of treatments per patient reported by the registry.

Methods: We performed a secondary analysis of deidentified data for all payers from 53 centers registered in the HBOTR from 2013 to 2022. We estimated the mean annual per-patient costs of HBO₂ based on Medicare (outpatient facility + physician) reimbursement fees adjusted to 2022 inflation using the Medicare Economic Index. Costs were calculated for the annual average number of treatments patients received each year and for a standard 40-treatment series. We estimated the 2022 costs of standard treatment protocols for HBO₂ indications treated in the outpatient setting.

Results: Generally, all costs decreased from 2013 to 2022. The facility cost per patient per 40 HBO₂ treatments decreased by 10.7% from $21,568.58 in 2013 to $19,488.00 in 2022. The physician cost per patient per 40 treatments substantially decreased by -37.8%, from $5,993.16 to $4,346.40. The total cost per patient per 40 treatments decreased by 15.6% from $27,561.74 to $23,834.40. In 2022, a single HBO₂ session cost $595.86. For different indications, estimated costs ranged from $2,383.4-$8,342.04 for crush injuries to $17,875.80-$35,751.60 for diabetic foot ulcers and delayed radiation injuries.

Conclusions: This real-world analysis of registry data demonstrates that the actual cost of HBO₂ is not nearly as costly as the literature has insinuated, and the per-patient cost to Medicare is decreasing, largely due to decreased physician costs.

Hypoxia, centralization of blood in pulmonary vessels, and increased cardiac output during physical exertion are the pathogenetic pathways of acute pulmonary edema observed during exposure to extraordinary environments. This study aimed to evaluate the effects of breath-hold diving at altitude, which exposes simultaneously to several of the stimuli mentioned above. To this aim, 11 healthy male experienced divers (age 18-52y) were evaluated (by Doppler echocardiography, lung echography to evaluate ultrasound lung B-lines (BL), hemoglobin saturation, arterial blood pressure, fractional NO (Nitrous Oxide) exhalation in basal condition (altitude 300m asl), at altitude (2507m asl) and after breath-hold diving at altitude. A significant increase in E/e' ratio (a Doppler-echocardiographic index of left atrial pressure) was observed at altitude, with no further change after the diving session. The number of BL significantly increased after diving at altitude as compared to basal conditions. Finally, fractional exhaled nitrous oxide was significantly reduced by altitude; no further change was observed after diving. Our results suggest that exposure to hypoxia may increase left ventricular filling pressure and, in turn, pulmonary capillary pressure. Breath-hold diving at altitude may contribute to interstitial edema (as evaluated by BL score), possibly because of physical efforts made during a diving session. The reduction of exhaled nitrous oxide at altitude confirms previous reports of nitrous oxide reduction after repeated exposure to hypoxic stimuli. This finding should be further investigated since reduced nitrous oxide production in hypoxic conditions has been reported in subjects prone to high-altitude pulmonary edema.

Introduction: Indigenous populations renowned for apneic diving have comparatively large spleen volumes. It has been proposed that a larger spleen translates to heightened apnea-induced splenic contraction and elevations in circulating hemoglobin mass (Hb_mass), which, in theory, improves O₂ carrying and/or CO₂/pH buffering capacities. However, the relation between resting spleen volume and apnea- induced increases in Hb_mass is unknown. Therefore, we tested the hypothesis that resting spleen volume is positively related to apnea-induced increases in total Hb_mass.

Methods: Fourteen healthy adults (six women; 29 ± 5 years) completed a two-minute carbon monoxide rebreathe procedure to measure pre-apneas Hb_mass and blood volume. Spleen length, width, and thickness were measured pre-and post-five maximal apneas via ultrasound. Spleen volume was calculated via the Pilström equation (test-retest CV:2 ± 2%). Hemoglobin concentration ([Hb]; g/dl) and hematocrit (%) were measured pre- and post-apneas via capillary blood samples. Post-apneas Hb_mass was estimated as post-apnea [Hb] x pre-apnea blood volume. Data are presented as mean ± SD.

Results: Spleen volume decreased from pre- (247 ± 95 mL) to post- (200 ± 82 mL, p<0.01) apneas. [Hb] (14.6 ± 1.2 vs. 14.9 ± 1.2 g/dL, p<0.01), hematocrit (44 ± 3 vs. 45 ± 3%, p=0.04), and Hb_mass (1025 ± 322 vs. 1046 ± 339 g, p=0.03) increased from pre- to post-apneas. Pre-apneas spleen volume was unrelated to post-apneas increases in Hb_mass (r=-0.02, p=0.47). O₂ (+28 ± 31 mL, p<0.01) and CO₂ (+31 ± 35 mL, p<0.01) carrying capacities increased post-apneas.

Conclusion: Larger spleen volume is not associated with a greater rise in apneas-induced increases in Hb_mass in non-apnea-trained healthy adults.

Barodontalgia, barometric pressure-induced dental pain, may occur during hyperbaric oxygen(HBO₂) therapy due to pressure changes. This case report presents an 8-year-old male patient with barodontalgia. The patient declared a severe toothache during HBO₂ therapy. The diving medicine specialist referred the patient to the dental clinician immediately. On clinical examination, the pain was thought to be caused by caries lesions of the deciduous teeth in the left maxillary molar region. Tooth extraction was suggested. After extraction, the patient continued hyperbaric oxygen therapy sessions without any pain. The patient was recommended for an intraoral and radiographic examination session one week after the extraction. In conclusion, caries lesions and faulty restorations should be examined before hyperbaric oxygen therapy sessions. Even though barodontalgia is a rare phenomenon, dental examination is essential to avoid these kinds of pain-related complications. All carious lesions and defective restorations must be treated, if necessary. Removal of faulty restorations and management of inflammation as part of the treatment is suggested before exposure to pressure changes.

We present two cases of cricoid chondronecrosis treated with hyperbaric oxygen (HBO₂) therapy. Both patients presented with biphasic stridor and dyspnea several weeks after an intubation event. Tracheostomy was ultimately performed for airway protection, followed by antibiotic treatment and outpatient HBO₂ therapy. Both patients were decannulated within six months of presentation and after at least 20 HBO₂ therapy sessions. Despite a small sample size, our findings are consistent with data supporting HBO₂ therapy's effects on tissue edema, neovascularization, and HBO₂ potentiation of antibiotic treatment and leukocyte function. We suggest HBO₂ therapy may have accelerated airway decannulation by way of infection resolution as well as the revitalization of upper airway tissues, ultimately renewing the structural integrity of the larynx. When presented with this rare but significant clinical challenge, physicians should be aware of the potential benefits of HBO₂ therapy.

The presence of a pneumothorax within a pressurized chamber represents unique diagnostic and management challenges. This is particularly the case in the medical and geographic remoteness of many chamber locations. Upon commencing chamber decompression, unvented intrapleural air expands. If its initial volume and/or degree of chamber pressure reduction is significant enough, a tension pneumothorax will result. Numerous reports chronicle failure to diagnose and manage in-chamber pneumothorax with resultant morbidity and one fatal outcome. Such cases have occurred in both medically remote and clinically based settings. This paper reviews pneumothorax and tension pneumothorax risk factors and clinical characteristics. It suggests primary medical management using the principle of oxygen-induced inherent unsaturation in concert with titrated chamber decompression designed to prevent intrapleural air expanding faster than it contracts. Should this conservative approach prove unsuccessful, and surgical venting becomes necessary or otherwise immediately indicated, interventional options are reviewed.

Carbon monoxide (CO) and cyanide poisoning are frequent causes of morbidity and mortality in cases of house and industrial fires. The 14th edition of guidelines from the Undersea and Hyperbaric Medical Society does not recommend hyperbaric oxygen (HBO₂) treatment in those patients who have suffered a cardiac arrest and had to receive cardiopulmonary resuscitation. In this paper, we describe the case of a 31-year-old patient who received HBO₂ treatment in the setting of cardiac arrest and survived.

This study aimed to investigate what factors determine freedivers' maximal static apnea dive time. We correlated some physical/physiological factors with male freedivers' maximum apnea diving duration. Thirty-six experienced male freedivers participated in this study. The divers participated in two days of the experiments. On the first day, apnea diving time, blood oxygen saturation (SpO₂), heart rate (HR), blood pressure (BP), stress index, and blood parameters were measured before, during, and after the apnea diving in the pool. On the second day, body composition, lung capacity, resting and maximal oxygen consumption (VO₂max), and the Wingate anaerobic power were measured in the laboratory. The data were analyzed with Pearson's Correlation using the SPSS 22 program. The correlation coefficient (R) of determination was set at 0.4, and the level of significance was set at p <0.05. There were positive correlations of diving experience, maximum SpO₂, and lung capacity with the maximum apnea time R>0.4, P<0.05). There were negative correlations of BMI, body fat percentage, body fat mass, minimum SpO₂, stress index, and total cholesterol with the maximum apnea diving time (R>-0.4, P<0.05). No correlations of age, height, weight, fat-free mass, skeletal muscle mass, HR, BP, blood glucose, beta- hydroxybutyrate, lactate, and hemoglobin levels with the maximum apnea diving time were observed (R<0.4, P>0.05). It is concluded that more experience in freediving, reduced body fat, extended SpO₂ range, and increased lung capacity are the performance predictors and beneficial for freedivers to improve their maximum apnea diving performance.

Background: Hyperbaric oxygen (HBO₂) therapy is an alternative method against the deleterious effects of ischemic/reperfusion (I/R) injury and its inflammatory response. This study assessed the effect of preoperative HBO₂ on patients undergoing pancreaticoduodenectomy.

Study design: Patients were randomized via a computer-generated algorithm. Patients in the HBO₂ cohort received two sessions of HBO₂ the evening before and the morning of surgery. Measurements of inflammatory mediators and self-assessed pain scales were determined pre-and postoperatively. In addition, perioperative variables and long-term survival were collected and analyzed. Data are presented as median (mean ± SD).

Results: 33 patients were included; 17 received preoperative HBO₂, and 16 did not. There were no intraoperative or postoperative statistical differences between patients with or without preoperative HBO₂. Erythrocyte sedimentation rate (ESR), IL-6, and IL-10 increased slightly before returning to normal, while TGF-alpha decreased before increasing. However, there were no differences with or without HBO₂. At postoperative day 30, the pain level measured with VAS score (Visual Analog Score) was lower after HBO₂ (1 ± 1.3 vs. 3 ± 3.0, p=0.05). Eleven (76%) patients in the HBO₂ cohort and 12 (75%) patients in the non- HBO₂ had malignant pathology. The percentage of positive lymph nodes in the HBO₂ was 7% compared to 14% in the non-HBO₂ (p<0.001). Overall survival was inferior after HBO₂ compared to the non- HBO₂ (p=0.03).

Conclusions: Preoperative HBO₂ did not affect perioperative outcomes or significantly change the inflammatory mediators for patients undergoing robotic pancreaticoduodenectomy. Long-term survival was inferior after preoperative HBO₂. Further randomized controlled studies are required to assess the full impact of this treatment on patients' prognosis.

An arterial gas embolism (AGE) is a potentially fatal complication of scuba diving that is related to insufficient exhalation during ascent. During breath-hold diving, an arterial gas embolism is unlikely because the volume of gas in the lungs generally cannot exceed the volume at the beginning of the dive. However, if a diver breathes from a gas source at any time during the dive, they are at risk for an AGE or other pulmonary overinflation syndromes (POIS). In this case report, a breath-hold diver suffered a suspected AGE due to rapidly ascending without exhalation following breathing from an air pocket at approximately 40 feet.