Diving and hyperbaric medicine最新文献

{"title":"A systematic review of electroencephalography in acute cerebral hypoxia: clinical and diving implications.","authors":"Nicole Ye Wong,&nbsp;Hanna van Waart,&nbsp;Jamie W Sleigh,&nbsp;Simon J Mitchell,&nbsp;Xavier Ce Vrijdag","doi":"10.28920/dhm53.3.268-280","DOIUrl":"10.28920/dhm53.3.268-280","url":null,"abstract":"<p><strong>Introduction: </strong>Hypoxia can cause central nervous system dysfunction and injury. Hypoxia is a particular risk during rebreather diving. Given its subtle symptom profile and its catastrophic consequences there is a need for reliable hypoxia monitoring. Electroencephalography (EEG) is being investigated as a real time monitor for multiple diving problems related to inspired gas, including hypoxia.</p><p><strong>Methods: </strong>A systematic literature search identified articles investigating the relationship between EEG changes and acute cerebral hypoxia in healthy adults. Quality of clinical evidence was assessed using the Newcastle-Ottawa scale.</p><p><strong>Results: </strong>Eighty-one studies were included for analysis. Only one study investigated divers. Twelve studies described quantitative EEG spectral power differences. Moderate hypoxia tended to result in increased alpha activity. With severe hypoxia, alpha activity decreased whilst delta and theta activities increased. However, since studies that utilised cognitive testing during the hypoxic exposure more frequently reported opposite results it appears cognitive processing might mask hypoxic EEG changes. Other analysis techniques (evoked potentials and electrical equivalents of dipole signals), demonstrated sustained regulation of autonomic responses despite worsening hypoxia. Other studies utilised quantitative EEG analysis techniques, (Bispectral index [BISTM], approximate entropy and Lempel-Ziv complexity). No change was reported in BISTM value, whilst an increase in approximate entropy and Lempel-Ziv complexity occurred with worsening hypoxia.</p><p><strong>Conclusions: </strong>Electroencephalographic frequency patterns change in response to acute cerebral hypoxia. There is paucity of literature on the relationship between quantitative EEG analysis techniques and cerebral hypoxia. Because of the conflicting results in EEG power frequency analysis, future research needs to quantitatively define a hypoxia-EEG response curve, and how it is altered by concurrent cognitive task loading.</p>","PeriodicalId":11296,"journal":{"name":"Diving and hyperbaric medicine","volume":"53 3","pages":"268-280"},"PeriodicalIF":0.9,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10597603/pdf/DHM-53-268.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10299459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Decompression procedures for transfer under pressure ('TUP') diving.","authors":"Jan Risberg,&nbsp;Pieter-Jan van Ooij,&nbsp;Olav Sande Eftedal","doi":"10.28920/dhm53.3.189-202","DOIUrl":"10.28920/dhm53.3.189-202","url":null,"abstract":"<p><strong>Background: </strong>There is an increasing interest in 'transfer under pressure' (TUP) decompression in commercial diving, bridging traditional surface-oriented diving and saturation diving. In TUP diving the diver is surfaced in a closed bell and transferred isobarically to a pressure chamber for final decompression to surface pressure.</p><p><strong>Methods: </strong>Tables for air diving and air and oxygen decompression have been compared for total decompression time (TDT), oxygen breathing time as well as high and low gradient factors (GF high and low). These have been considered surrogate outcome measures of estimated decompression sickness probability (P_DCS).</p><p><strong>Results: </strong>Six decompression tables from DadCoDat (DCD, The Netherlands), Defence and Civil Institute of Environmental Medicine (DCIEM, Canada), Comex MT92 tables (France) and the United States Navy (USN) have been compared. In general, USN and DCD procedures advised longer TDT and oxygen breathing time and had a lower GF high compared to MT92 and DCIEM tables. GF low was significantly higher in USN procedures compared to DCD and one of the MT92 tables due to a shallower first stop in many USN profiles compared to the two others. Allowance and restrictions for repetitive diving varied extensively between the six procedures. While USN procedures have been risk-assessed by probabilistic models, no detailed documentation is available for any of the tables regarding validation in experimental and operational diving.</p><p><strong>Conclusions: </strong>Absence of experimental testing of the candidate tables precludes firm conclusions regarding differences in P_DCS. All candidate tables are recognised internationally as well as within their national jurisdictions, and final decisions on procedure preference may depend on factors other than estimated P_DCS. USN and DCD procedures would be expected to have lower P_DCS than MT92 and DCIEM procedures, but the magnitude of these differences is not known.</p>","PeriodicalId":11296,"journal":{"name":"Diving and hyperbaric medicine","volume":"53 3","pages":"189-202"},"PeriodicalIF":0.9,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10597602/pdf/DHM-53-189.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10306279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of a new hyperbaric oxygen ventilator during volume-controlled ventilation.","authors":"Cong Wang, Lianbi Xue, Qiuhong Yu, Yaling Liu, Ziqi Ren, Ying Liu","doi":"10.28920/dhm53.2.129-137","DOIUrl":"10.28920/dhm53.2.129-137","url":null,"abstract":"<p><strong>Introduction: </strong>The performance of the Shangrila590 hyperbaric ventilator (Beijing Aeonmed Company, Beijing, China) was evaluated during volume-controlled ventilation.</p><p><strong>Methods: </strong>Experiments were conducted in a multiplace hyperbaric chamber at 101, 152, 203, and 284 kPa (1.0, 1.5, 2.0 and 2.8 atmospheres absolute [atm abs]). With the ventilator in volume control ventilation (VCV) mode and connected to a test lung, comparison was made of the set tidal volume (VTset) versus delivered tidal volume (VT) and minute volume (MV) at VTset between 400 and 1,000 mL. Peak inspiratory pressure was also recorded. All measurements were made across 20 respiratory cycles.</p><p><strong>Results: </strong>Across all ambient pressures and ventilator settings the difference between VTset and actual VT and between predicted MV and actual MV were small and clinicially insignificant despite reaching statistical significance. Predictably, Ppeak increased at higher ambient pressures. With VTset 1,000 mL at 2.8 atm abs the ventilator produced significantly greater VT, MV and Ppeak.</p><p><strong>Conclusions: </strong>This new ventilator designed for use in hyperbaric environments performs well. It provides relatively stable VT and MV during VCV with VTset from 400 mL to 800 mL at ambient pressures from 1.0 to 2.8 atm abs, as well as VTset 1,000 mL at ambient pressures from 1.0 to 2.0 atm abs.</p>","PeriodicalId":11296,"journal":{"name":"Diving and hyperbaric medicine","volume":"53 2","pages":"129-137"},"PeriodicalIF":0.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10584397/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10048473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hyperbaric medicine in Canadian undergraduate medical school curriculum.","authors":"Zoé Talbot, Alex Lee, Sylvain Boet","doi":"10.28920/dhm53.2.138-141","DOIUrl":"10.28920/dhm53.2.138-141","url":null,"abstract":"<p><strong>Introduction: </strong>Hyperbaric oxygen treatment (HBOT) has fourteen approved indications in the management of acute and chronic diseases in various medical specialties. However, lack of physician knowledge and exposure to hyperbaric medicine may hinder the ability of patients to access this treatment option for approved indications. We aimed to determine the prevalence and nature of HBOT-related learning objectives in Canadian undergraduate medical education programs.</p><p><strong>Methods: </strong>Pre-clerkship and clerkship learning objectives from responding Canadian medical schools' curricula were reviewed. These were acquired through the school websites or by emailing the faculties. Descriptive statistics were used to summarise the number of hyperbaric medicine objectives taught in Canadian medical schools, and within each institution.</p><p><strong>Results: </strong>Learning objectives from seven of the 17 Canadian medical schools were received and reviewed. From the curriculum of the responding schools, only one objective was found to be related to hyperbaric medicine. Hyperbaric medicine was absent from the other six schools' objectives.</p><p><strong>Conclusions: </strong>Based on the responding Canadian medical schools, hyperbaric medicine objectives were mostly absent from undergraduate medical curricula. These findings illustrate a possible gap in HBOT education and the need for discussion regarding the design and implementation of HBOT educational initiatives in medical training.</p>","PeriodicalId":11296,"journal":{"name":"Diving and hyperbaric medicine","volume":"53 2","pages":"138-141"},"PeriodicalIF":0.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10584399/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10048474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hemiplegia resulting from acute carbon monoxide poisoning.","authors":"Burak Turgut, Kübra Canarslan Demir, G B Sarıyerli Dursun, Taylan Zaman","doi":"10.28920/dhm53.2.155-157","DOIUrl":"10.28920/dhm53.2.155-157","url":null,"abstract":"<p><p>Carbon monoxide (CO) poisoning can cause neurological complications such as movement disorders and cognitive impairment through hypoxic brain damage. Although peripheral neuropathy of the lower extremities is a known complication of CO poisoning, hemiplegia is very rare. In our case, a patient who developed left hemiplegia due to acute CO poisoning received early hyperbaric oxygen treatment (HBOT). The patient had left hemiplegia and anisocoria at the beginning of HBOT. Her Glasgow coma score was 8. A total of five sessions of HBOT at 243.2 kPa for 120 minutes were provided. At the end of the 5th session, the patient's hemiplegia and anisocoria were completely resolved. Her Glasgow coma score was 15. After nine months of follow-up, she continues to live independently with no sequelae, including delayed neurological sequelae. Clinicians should be aware that CO poisoning can (rarely) present with hemiplegia.</p>","PeriodicalId":11296,"journal":{"name":"Diving and hyperbaric medicine","volume":"53 2","pages":"155-157"},"PeriodicalIF":0.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10584395/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9692076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How fit are military hyperbaric personnel after an asymptomatic or mild symptomatic COVID-19 infection? A retrospective study.","authors":"Jan-Peter Schaap, Margy E Zuluaga Fernandez, Antoinette Houtkooper, Edwin L Endert, Pieter-Jan A M van Ooij","doi":"10.28920/dhm53.2.120-128","DOIUrl":"10.28920/dhm53.2.120-128","url":null,"abstract":"<p><strong>Introduction: </strong>In the diving community there is a special need to know if asymptomatic or mild COVID-19 disease impacts the cardiopulmonary functioning of individuals with occupational exposure to extreme environments. To date, no controlled studies have been conducted comparing COVID-19-infected hyperbaric employees and non-COVID-19-infected peers in a military setting.</p><p><strong>Methods: </strong>Between June 2020 and June 2021, healthy, hyperbaric, military personnel aged between 18 and 54 years old, who had recovered from asymptomatic or subclinical COVID-19 disease at least one month earlier, were analysed. Non-COVID-infected peers with medical assessments during the same period were used as the control group. Somatometry, spirometry, VO₂ max, and DLCO were measured for each group.</p><p><strong>Results: </strong>No clinically relevant differences in somatometry, lung function tests, and exercise testing were found between the COVID-19 group and the controls. However, the percentage of individuals with a decrease in estimated VO2-max of 10% or more was significantly greater in the COVID group than in the control group (24 vs. 7.8%, P = 0.004).</p><p><strong>Conclusions: </strong>After asymptomatic or mild symptomatic COVID-19 infections, military hyperbaric employees are as fit as those who had not encountered COVID-19. As this research was based on a military population, it cannot be extrapolated to a nonmilitary population. Further studies in nonmilitary populations are necessary to determine the medical relevance of the present findings.</p>","PeriodicalId":11296,"journal":{"name":"Diving and hyperbaric medicine","volume":"53 2","pages":"120-128"},"PeriodicalIF":0.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10584392/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9692075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effectiveness of hyperbaric chamber ventilation.","authors":"Lyubisa Matity, Francois Burman, Jacek Kot, Joseph Caruana","doi":"10.28920/dhm53.2.85-91","DOIUrl":"10.28920/dhm53.2.85-91","url":null,"abstract":"<p><strong>Introduction: </strong>Hyperbaric chamber ventilation (HCV) refers to the intentional introduction of fresh gas, whether air, oxygen, or heliox, into a pressurised hyperbaric chamber in order to remove stale or otherwise compromised gas. The minimum required continuous HCV rate is usually determined by mathematical models derived from the contaminant mass balance within a well-stirred compartment. Non-uniform contaminant distribution patterns inside a hyperbaric chamber could emerge and invalidate the predictions of well-stirred models.</p><p><strong>Methods: </strong>Contaminant distribution was investigated inside a clinical hyperbaric chamber with the aim of comparing well-stirred model predictions with the actual contaminant concentration measurements.</p><p><strong>Results: </strong>Local ventilation effectiveness inside a clinical hyperbaric chamber may be compromised, leading to higher contaminant concentration values compared to the predictions of a mathematical model with a well-stirred assumption.</p><p><strong>Conclusions: </strong>A well-stirred assumption in mathematical models is a useful simplification that allows reasonably accurate estimates of HCV requirements. However, local ventilation effectiveness values in a particular hyperbaric chamber might vary, with the potential for hazardous contaminant accumulation in under-ventilated zones.</p>","PeriodicalId":11296,"journal":{"name":"Diving and hyperbaric medicine","volume":"53 2","pages":"85-91"},"PeriodicalIF":0.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10586871/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10067067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hyperbaric oxygen and treadmill exercise partially prevented bone loss and bone microarchitecture deterioration in ovariectomized rats.","authors":"Xiaoling Peng, Binli Gao, Xiangxiu Wang, Xiaohong Qin, Mei Peng, Xianrong Zeng","doi":"10.28920/dhm53.2.111-119","DOIUrl":"10.28920/dhm53.2.111-119","url":null,"abstract":"<p><strong>Introduction: </strong>Previous studies have demonstrated the beneficial effects of treadmill exercise (EX) on osteoporosis, and of hyperbaric oxygen (HBO) on osteoblast and osteoclast formation in vitro. We investigated the effects of HBO and the combination of HBO and EX on osteoporosis in ovariectomized rats.</p><p><strong>Methods: </strong>Forty 3-month-old female Sprague-Dawley rats were randomly divided into 5 groups (n = 8): a sham control group (Control); an ovariectomy group; an ovariectomy with treadmill exercise treatment group; an ovariectomy with HBO treatment group; and an ovariectomy with HBO treatment combined with treadmill exercise group. The HBO exposures were 203 kPa, 85-90% O₂, 90 min and the exercise regimen was 20 m·min⁻¹, 40 min·day¹, 5° slope. Both treatments were administered once daily, five days a week for 12 weeks until the rats were sacrificed.</p><p><strong>Results: </strong>All three treatments (HBO, exercise, and both combined) significantly promoted the expression of the osteoblast-related gene and oxidative metabolism-related gene (PGC-1α). They also exerted significant inhibitory effects on the osteoclast-related mRNA expression (RANKL) and bone resorption marker CTX-I. Additionally, exercise and the combination exercise-HBO treatment increased serum superoxide dysmutase (SOD) and sclerostin expression. No significant between-group difference was observed.</p><p><strong>Conclusions: </strong>Hyperbaric oxygen, exercise, and the combination ameliorated bone microarchitecture deterioration and ovariectomy-induced bone loss in rats, and these inhibitory effects may be associated with the increased SOD and up-regulated PGC-1α.</p>","PeriodicalId":11296,"journal":{"name":"Diving and hyperbaric medicine","volume":"53 2","pages":"111-119"},"PeriodicalIF":0.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10584393/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10067069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Successful hyperbaric oxygen treatment of a patient with a HeartMate III left ventricular assist device.","authors":"Arun Ilancheran, Ian Millar, Theo Tsouras","doi":"10.28920/dhm53.2.147-150","DOIUrl":"10.28920/dhm53.2.147-150","url":null,"abstract":"<p><p>A 53-year-old woman with a HeartMate III left ventricular assist device (LVAD) was successfully treated under hyperbaric conditions for haemorrhagic cystitis. The HeartMate III LVAD inserted in this patient had not previously been tested or certified for use under hyperbaric conditions. To our knowledge this is the first report of the HeartMate III LVAD being used to support a patient undergoing hyperbaric treatment. The overview detailed here of the safety and technical aspects of managing this patient for hyperbaric treatment was possible due to the collaboration of a multi-disciplinary team. We believe that our experience has demonstrated a pathway to safe hyperbaric treatment of patients dependent upon a HeartMate III LVAD.</p>","PeriodicalId":11296,"journal":{"name":"Diving and hyperbaric medicine","volume":"53 2","pages":"147-150"},"PeriodicalIF":0.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10584400/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10048469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Successful delayed treatment of acute glans penis ischaemia after adult circumcision: a case report.","authors":"Kenneth Lo, Darren Katz, Vincent Chan, Ian Miler","doi":"10.28920/dhm53.2.151-154","DOIUrl":"10.28920/dhm53.2.151-154","url":null,"abstract":"<p><p>Penile glans ischaemia post-circumcision is very rare. A 20-year-old male presented with glans ischaemia following an elective circumcision and was successfully treated with a combination of subcutaneous injection of low molecular weight heparin 0.5 mg·kg⁻¹ twice-daily, oral Tadalafil 5 mg once-daily for three days and 12 hyperbaric oxygen treatments at 243 kPa (2.4 atmospheres absolute) beginning 48 hours after the onset of ischaemia.</p>","PeriodicalId":11296,"journal":{"name":"Diving and hyperbaric medicine","volume":"53 2","pages":"151-154"},"PeriodicalIF":0.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10584398/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10067066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}