2024 March;54(1)
Diving Hyperb Med. 2024 31 March;54(1):2−8. doi: 10.28920/dhm54.1.2-8. PMID: 38507904.
Efficacy of searching in biomedical databases beyond MEDLINE in identifying randomised controlled trials on hyperbaric oxygen treatment
Hira Khan1, Mohammad Sindeed Islam2, Manvinder Kaur3, Joseph K Burns1,3, Cole Etherington1,3, Pierre-Marc Dion2, Sarah Alsayadi4, Sylvain Boet1,3,5,6
1 Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
2 Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
3 Department of Anesthesiology and Pain Medicine, The Ottawa Hospital, Ottawa, ON, Canada
4 Faculty of Science, University of Ottawa, Ottawa, ON, Canada
5 Department of Innovation in Medical Education, University of Ottawa, Ottawa, ON, Canada
6 Institut du Savoir Montfort, Ottawa, ON, Canada
Corresponding author: Dr Sylvain Boet, 1053 Carling Avenue, Ottawa, ON K1Y 4E9, ON, Canada
Keywords
Biomedical databases; Research methods; Systematic review
Abstract
(Khan K, Islam MS, Kaur M, Burns JK, Etherington C, Dion P-M, Alsayadi S, Boet S. Efficacy of searching in biomedical databases beyond MEDLINE in identifying randomised controlled trials on hyperbaric oxygen treatment. Diving and Hyperbaric Medicine. 2024 31 March;54(1):2−8. doi: 10.28920/dhm54.1.2-8. PMID: 38507904.)
Introduction: Literature searches are routinely used by researchers for conducting systematic reviews as well as by healthcare providers, and sometimes patients, to quickly guide their clinical decisions. Using more than one database is generally recommended but may not always be necessary for some fields. This study aimed to determine the added value of searching additional databases beyond MEDLINE when conducting a literature search of hyperbaric oxygen treatment (HBOT) randomised controlled trials (RCTs).
Methods: This study consisted of two phases: a scoping review of all RCTs in the field of HBOT, followed by a a statistical analysis of sensitivity, precision, ‘number needed to read’ (NNR) and ‘number unique’ included by individual biomedical databases. MEDLINE, Embase, Cochrane Central Register of Control Trials (CENTRAL), and Cumulated Index to Nursing and Allied Health Literature (CINAHL) were searched without date or language restrictions up to December 31, 2022. Screening and data extraction were conducted in duplicate by pairs of independent reviewers. RCTs were included if they involved human subjects and HBOT was offered either on its own or in combination with other treatments.
Results: Out of 5,840 different citations identified, 367 were included for analysis. CENTRAL was the most sensitive (87.2%) and had the most unique references (7.1%). MEDLINE had the highest precision (23.8%) and optimal NNR (four). Among included references, 14.2% were unique to a single database.
Conclusions: Systematic reviews of RCTs in HBOT should always utilise multiple databases, which at minimum include MEDLINE, Embase, CENTRAL and CINAHL.
Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.
Publication Type: Original article
Diving Hyperb Med. 2024 31 March;54(1):9−15. doi: 10.28920/dhm54.1.9-15. PMID:38507905.
Hyperbaric oxygen treatment for infants: retrospective analysis of 54 patients treated in two tertiary care centres
Kubra Ozgok Kangal1, Bengusu Mirasoglu2
1 Department of Underwater and Hyperbaric Medicine, University of Health Sciences, Gulhane Faculty of Medicine, Gulhane Research and Training Hospital, Ankara, Turkey
2 Department of Underwater and Hyperbaric Medicine, Istanbul University, Istanbul Faculty of Medicine, Istanbul, Turkey
Corresponding author: Associate Professor Kubra Ozgok Kangal, Gen. Dr. Tevfik Saglam Cad. SBÜ-Gülhane Eğitim ve Araştırma Hastanesi, Sualtı Hekimliği ve Hiperbarik Tıp Kliniği, Etlik/Ankara, Turkey
Keywords
Hyperbaric medicine; Neonate; Newborn; Premature
Abstract
(Ozgok Kangal K, Mirasoglu B. Hyperbaric oxygen treatment for infants: retrospective analysis of 54 patients treated in two tertiary care centres. Diving and Hyperbaric Medicine. 2024 31 March;54(1):9−15. doi: 10.28920/dhm54.1.9-15. PMID:38507905.)
Introduction: We aimed to analyse the outcomes of hyperbaric oxygen treatment (HBOT) and describe difficulties encountered in infants, a rare patient population in this therapeutic intervention, with limited scientific reports.
Methods: This was a retrospective analysis of patients 12 months old or younger who underwent HBOT in two different institutions. Demographic data, clinical presentation, HBOT indication, chamber type, oxygen delivery method, total number of treatments, outcome and complications were extracted from clinical records.
Results: There were 54 infants in our study. The patients’ median age was 3.5 (range 0–12) months. The major HBOT indication was acute carbon monoxide intoxication (n = 32). A total of 275 HBOT treatments were administered, mostly performed in multiplace chambers (n = 196, 71%). Only one patient (2%) required mechanical ventilation. Acute signs were fully resolved in the most patients (n = 40, 74%). No complications related to HBOT were reported.
Conclusions: This study suggests that HBOT may be a safe and effective treatment for infants. Paediatricians should consider HBOT when indicated in infants even for the preterm age group.
Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.
Publication Type: Original article
Diving Hyperb Med. 2024 31 March;54(1):16−22. doi: 10.28920/dhm54.1.16-22. PMID: 38507906.
Effect of hyperbaric oxygen treatment on ischaemia-reperfusion injury in rats detorsioned after experimental ovarian torsion
Eralp Bulutlar1, Ali Yilmaz2, Gizem Berfin Uluutku Bulutlar3, Yavuz Aslan4, Hale Nur Bozdağ5, Zafer Küçükodaci6
1 Zeynep Kamil Gynecology and Obstetrics Training and Research Hospital, İstanbul, Turkey
2 Kartal Lütfü Kırdar Training and Research Hospital İstanbul, Turkey
3 Haydarpaşa Numune Training and Research Hospital, İstanbul, Turkey
4 Sultan Abdulhamid Han Research and Training Hospital
5 VM Medical Park Maltepe Hastanesi, İstanbul , Turkey
6 Anadolu Sağlık Merkezi, Gebze, Kocaeli, Turkey
Corresponding author: Dr Eralp Bulutlar, Başakşehir Çam and Sakura City Hospital, Başakşehir Olimpiyat Bulvarı Yolu, 34480 Başakşehir, İstanbul, Turkey
ORCiD: 0000-0002-2246-4899
Keywords
Animal model; Antioxidants; Experimental; Hyperbaric research; Inflammation
Abstract
(Bulutlar E, Yilmaz A, Uluutku Bulutlar GB, Aslan Y, Bozdağ HN, Küçükodaci Z. Effect of hyperbaric oxygen treatment on ischaemia-reperfusion injury in rats detorsioned after experimental ovarian torsion. Diving and Hyperbaric Medicine. 2024 31 March;54(1):16−22. doi: 10.28920/dhm54.1.16-22. PMID: 38507906.)
Introduction: This study aimed to investigate whether hyperbaric oxygen treatment (HBOT) could ameliorate ischaemia-reperfusion injury in a rat model of ovarian torsion-detorsion.
Methods: Twenty-seven rats were divided among four groups: surgical sham rats (S) (n = 6) underwent identical anaesthesia and surgical incisions to other groups (n = 7 per group) but with no ovary intervention; torsion rats (T) underwent laparotomy, ovarian torsion, relaparotomy and sacrifice after three hours; torsion and detorsion rats (T/DT) underwent laparotomy, ovarian torsion (three hours), relaparotomy and detorsion, and sacrifice after one week; torsion, detorsion, hyperbaric oxygen rats (T/DT/HBOT) underwent laparotomy, ovarian torsion, relaparotomy and detorsion, and sacrifice after one week during which HBOT was provided 21 times (100% oxygen at 600 kPa for 50 min). In all groups blood collection for markers of oxidative stress or related responses, and ovary collection for histology were performed after sacrifice.
Results: When the T/DT, and T/DT/HBOT groups were compared, 8-hydroxy-2′-deoxyguanosine (a marker of oxidative damage to DNA) and malondialdehyde (a product of lipid peroxidation) levels were lower in the T/DT/HBOT group. Anti-Mullerian hormone levels were higher in the T/DT/HBOT group compared to the T/DT group. In addition, oedema, vascular occlusion, neutrophilic infiltration and follicular cell damage were less in the T/DT/HBOT group
than in the T/DT group.
Conclusions: When biochemical and histopathological findings were evaluated together, HBOT appeared reduce ovarian ischaemia / reperfusion injury in this rat model of ovarian torsion-detorsion.
Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.
Publication Type: Original article
Diving Hyperb Med. 2024 31 March;54(1):23−38. doi: 10.28920/dhm54.1.23-38. PMID: 38507907.
Review of saturation decompression procedures used in commercial diving
Jean-Pierre Imbert1, Lyubisa Matity2, Jean-Yves Massimelli3, Philip Bryson4
1 Divetech, 1543 chemin des vignasses, 06410 Biot, France
2 Hyperbaric and Tissue Viability Unit, Gozo General Hospital, Malta
3 CHU de Nice, Hôpital Pasteur, 30 avenue de la voie romaine, 06001 Nice, France
4 International SOS, Forest Grove House, Foresterhill Road, Aberdeen, AB25 2ZP, UK
Corresponding author: Jean Pierre Imbert, Divetech, 1543 ch des vignasses 0641Biot, France
Keywords
Decompression tables; Occupational diving; Saturation diving
Abstract
(Imbert J-P, Matity L, Massimelli J-Y, Bryson P. Review of saturation decompression procedures used in commercial diving. Diving and Hyperbaric Medicine. 2024 31 March;54(1):23−38. doi: 10.28920/dhm54.1.23-38. PMID: 38507907.)
Introduction: This is a review of commercial heliox saturation decompression procedures. The scope does not include compression, storage depth or bell excursion dive procedures. The objectives are to: identify the sources of the procedures; trace their evolution; describe the current practice; and detect relevant trends.
Methods: Eleven international commercial diving companies provided their diving manuals for review under a confidentiality agreement.
Results: Modern commercial diving saturation procedures are derived from a small number of original procedures (United States Navy, Comex, and NORSOK). In the absence of relevant scientific studies since the late 80’s, the companies have empirically adapted these procedures according to their needs and experience. Such adaptation has caused differences in decompression rates shallower than 60 msw, decompression rest stops and the decision to decompress linearly or stepwise. Nevertheless, the decompression procedures present a remarkable homogeneity in chamber PO2 and daily decompression rates when deeper than 60 msw. The companies have also developed common rules of good practice; no final decompression should start with an initial ascending excursion; a minimum hold is required before starting a final decompression after an excursion dive. Recommendation is made for the divers to exercise during decompression.
Conclusions: We observed a trend towards harmonisation within the companies that enforce international procedures, and, between companies through cooperation inside the committees of the industry associations.
Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.
Publication Type: Original article
Diving Hyperb Med. 2024 31 March;54(1):39−46. doi: 10.28920/dhm54.1.39-46. PMID: 38507908.
Chain of events analysis in diving accidents treated by the Royal Netherlands Navy 1966–2023
Benjamin L Turner1, Pieter-Jan AM van Ooij1,2, Thijs T Wingelaar1,3, Rob A van Hulst3, Edwin L Endert1, Paul Clarijs1, Rigo Hoencamp4,5,6
1 Royal Netherlands Navy Diving and Submarine Medical Centre, Den Helder, The Netherlands
2 Department of Respiratory Medicine, Amsterdam UMC, Location AMC, University of Amsterdam, Amsterdam, The Netherlands
3 Department of Anesthesiology, Amsterdam UMC, Location AMC, University of Amsterdam, Amsterdam, The Netherlands
4 Department of Surgery, Alrijne Hospital, Leiderdorp, the Netherlands
5 Trauma Research Unit, Department of Trauma Surgery, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
6 Defence Healthcare Organization, Ministry of Defence, Utrecht, the Netherlands
Corresponding author: Mr Benjamin L Turner, Royal Netherlands Navy Diving and Submarine Medical Centre, Den Helder, The Netherlands
ORCiD: 0009-0004-6606-9788
Keywords
Arterial gas embolism; Decompression sickness; Incidents; Risk factors; Safety; Underwater hazards
Abstract
(Turner BL, van Ooij P-JAM, Wingelaar TT, van Hulst RA, Endert EL, Clarijs P, Hoencamp R. Chain of events analysis in diving accidents treated by the Royal Netherlands Navy 1966-2023. Diving and Hyperbaric Medicine. 2024 31 March;54(1):39−46. doi: 10.28920/dhm54.1.39-46. PMID: 38507908.)
Introduction: Diving injuries are influenced by a multitude of factors. Literature analysing the full chain of events in diving accidents influencing the occurrence of diving injuries is limited. A previously published ‘chain of events analysis’ (CEA) framework consists of five steps that may sequentially lead to a diving fatality. This study applied four of these steps to predominately non-lethal diving injuries and aims to determine the causes of diving injuries sustained by divers treated by the Diving Medical Centre of the Royal Netherlands Navy.
Methods: This retrospective cohort study was performed on diving injuries treated by the Diving Medical Centre between 1966 and 2023. Baseline characteristics and information pertinent to all four steps of the reduced CEA model were extracted and recorded in a database.
Results: A total of 288 cases met the inclusion criteria. In 111 cases, all four steps of the CEA model could be applied. Predisposing factors were identified in 261 (90%) cases, triggers in 142 (49%), disabling agents in 195 (68%), and 228 (79%) contained a (possible-) disabling condition. The sustained diving injury led to a fatality in seven cases (2%). The most frequent predisposing factor was health conditions (58%). Exertion (19%), primary diver errors (18%), and faulty equipment (17%) were the most frequently identified triggers. The ascent was the most frequent disabling agent (52%).
Conclusions: The CEA framework was found to be a valuable tool in this analysis. Health factors present before diving were identified as the most frequent predisposing factors. Arterial gas emboli were the most lethal injury mechanism.
Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.
Publication Type: Original article
Diving Hyperb Med. 2024 31 March;54(1):47−56. doi: 10.28920/dhm54.1.47-56. PMID: 38507909
Reported outcome measures in necrotising soft tissue infections: a systematic review
Jonathan Wackett1, Bridget Devaney2,3,4, Raymond Chau5, Joshua Ho5, Nicholas King5, Jasleen Grewal1, Joshua Armstrong6, Biswadev Mitra2,4
1 Department of Medicine, Alfred Health, Melbourne, Australia
2 Emergency and Trauma Centre, Alfred Health, Melbourne, Australia
3 Department of Intensive Care and Hyperbaric Medicine, Alfred Health, Melbourne, Australia
4 Department of Epidemiology and Preventative Medicine, Monash University, Melbourne, Australia
5 Monash Health, Melbourne, Australia
6 Barwon Health, Geelong, Australia
Corresponding author: Dr Bridget Devaney, Head of Hyperbaric Medicine, Alfred Health, 55 Commercial Road, Melbourne, VIC 3004, Australia
ORCiD: 0000-0001-6521-418X
Keywords
Fournier’s gangrene; Gas gangrene; Hyperbaric oxygen treatment; Intensive care medicine; Systematic review
Abstract
(Wackett J, Devaney B, Chau R, Ho J, King N, Grewal J, Armstrong J, Mitra B. Reported outcome measures in necrotising soft tissue infections: a systematic review. Diving and Hyperbaric Medicine. 2024 31 March;54(1):47−56. doi: 10.28920/dhm54.1.47-56. PMID: 38507909.)
Introduction: There are inconsistencies in outcome reporting for patients with necrotising soft tissue infections (NSTI). The aim of this study was to evaluate reported outcome measures in NSTI literature that could inform a core outcome set (COS) such as could be used in a study of hyperbaric oxygen in this indication.
Methods: A systematic review of all NSTI literature identified from Cochrane, Ovid MEDLINE and Scopus databases as well as grey literature sources OpenGrey and the New York Academy of Medicine databases which met inclusion criteria and were published between 2010 and 2020 was performed. Studies were included if they reported on > 5 cases and presented clinical endpoints, patient related outcomes, or resource utilisation in NSTI patients. Studies did not have to include intervention. Two independent researchers then extracted reported outcome measures. Similar outcomes were grouped and classified into domains to produce a structured inventory. An attempt was made to identify trends in outcome measures over time and by study design.
Results: Three hundred and seventy-five studies were identified and included a total of 311 outcome measures. Forty eight percent (150/311) of outcome measures were reported by two or more studies. The four most frequently reported outcome measures were mortality without time specified, length of hospital stay, amputation performed, and number of debridements, reported in 298 (79.5%), 260 (69.3%), 156 (41.6%) and 151 (40.3%) studies respectively. Mortality outcomes were reported in 23 different ways. Randomised controlled trials (RCTs) were more likely to report 28-day mortality or 90-day mortality. The second most frequent amputation related outcome was level of amputation, reported in 7.5% (28/375) of studies. The most commonly reported patient-centred outcome was the SF-36 which was reported in 1.6% (6/375) of all studies and in 2/10 RCTs.
Conclusions: There was wide variance in outcome measures in NSTI studies, further highlighting the need for a COS.
Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.
Publication Type: Review article
Diving Hyperb Med. 2024 31 March;54(1):57−60. doi: 10.28920/dhm54.1.57-60. PMID: 38507910.
Equipoise: an important ethical consideration when contemplating participation in a randomised controlled trial of hyperbaric oxygen treatment in necrotising soft tissue infections
Bridget Devaney1,2,3
1 Emergency and Trauma Centre, Alfred Health, Melbourne, Australia
2 Department of Intensive Care and Hyperbaric Medicine, Alfred Health, Melbourne, Australia
3 Department of Epidemiology and Preventative Medicine, Monash University, Melbourne, Australia
Corresponding author: Dr Bridget Devaney, Head of Hyperbaric Medicine, Alfred Health, 55 Commercial Road, Melbourne, VIC 3004, Australia
ORCiD: 0000-0001-6521-418X
Keywords
Clinical trials; Ethics; Hyperbaric research
Abstract
(Devaney B. Equipoise: an important ethical consideration when contemplating participation in a randomised controlled trial of hyperbaric oxygen treatment in necrotising soft tissue infections. Diving and Hyperbaric Medicine. 2024 31 March;54(1):57−60. doi: 10.28920/dhm54.1.57-60. PMID: 38507910.)
A proposal for a large, multi-centre, randomised controlled trial investigating the role of hyperbaric oxygen treatment (HBOT) in necrotising soft tissue infections (NSTI) has led to much discussion locally and internationally about whether participation is ethical for a centre where stakeholders already consider HBOT standard practice. This article systematically addresses the concept of clinical equipoise specific to the role of HBOT in NSTI, and presents a series of considerations to be taken into account by key stakeholders at potential participating sites.
Copyright: This article is the copyright of the author who grants Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.
Publication Type: World as it is
Diving Hyperb Med. 2024 31 March;54(1):61−64. doi: 10.28920/dhm54.1.61-64. PMID: 38507911.
Secondary deterioration in a patient with cerebral and coronary arterial gas embolism after brief symptom resolution: a case report
Ryota Tsushima1, Kosuke Mori2, Shohei Imaki1
1 Yokohama Municipal Citizen’s Hospital 1-1, Mitsuzawanishi-chou, Kanagawa-ku, Yokohama-city, Kanagawa-ken 221-0855, Japan
2 Yokohama Minami Kyosai Hospital 1-21-1, Mutsurahigashi, Kanazawa-ku, Yokohama- city, Kanagawa-ken 236-0037, Japan
Corresponding author: Dr Ryota Tsushima, Yokohama Municipal Citizen’s Hospital 1-1, Mitsuzawanishi-chou, Kanagawa-ku, Yokohama-city, Kanagawa-ken 221-0855, Japan
Keywords
Air embolism; Case reports; Hyperbaric oxygen treatment
Abstract
(Tsushima R, Mori K, Imaki S. Secondary deterioration in a patient with cerebral and coronary arterial gas embolism after brief symptom resolution: a case report. Diving and Hyperbaric Medicine. 2024 31 March;54(1):61−64. doi: 10.28920/dhm54.1.61-64. PMID: 38507911.)
Introduction: Hyperbaric oxygen treatment (HBOT) is recommended for arterial gas embolism (AGE) with severe symptoms. However, once symptoms subside, there may be a dilemma to treat or not.
Case presentation: A 71-year-old man was noted to have a mass shadow in his left lung, and a transbronchial biopsy was performed with sedation. Flumazenil was intravenously administered at the end of the procedure. However, the patient remained comatose and developed bradycardia, hypotension, and ST-segment elevation in lead II. Although the ST changes spontaneously resolved, the patient had prolonged disorientation. Whole- body computed tomography revealed several black rounded lucencies in the left ventricle and brain, confirming AGE. The patient received oxygen and remained supine. His neurological symptoms gradually improved but worsened again, necessitating HBOT. HBOT was performed seven times, after which neurological symptoms resolved almost completely.
Conclusions: AGE can secondarily deteriorate after symptoms have subsided. We recommend that HBOT be performed promptly once severe symptoms appear, even if they resolve spontaneously.
Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.
Publication Type: Case report
Diving Hyperb Med. 2024 31 March;54(1):65−68. doi: 10.28920/dhm54.1.65-68. PMID: 38507912.
Hyperbaric oxygen for the treatment of carbon monoxide-induced delayed neurological sequelae: a case report and review of the literature
Zebedee KR Wong1, Colin KA Teo1, James WM Kwek1, Soo Joang Kim2, Hooi Geok See3
1 Navy Medical Service, Republic of Singapore Navy, Singapore
2 Hyperbaric and Diving Medicine Centre, Singapore General Hospital, Singapore
3 Division of Anaesthesiology and Perioperative Medicine, Singapore General Hospital, Singapore
Corresponding author: Dr Zebedee KR Wong, Navy Medical Service, Republic of Singapore Navy, Singapore
ORCiD: 0009-0000-0081-3915
Keywords
Hyperbaric medicine; Morbidity; Pain; Neurology; Psychology; Radiological imaging; Toxicity
Abstract
(Wong ZKR, Teo CKA, Kwek JWM, Kim SJ, See HG. Hyperbaric oxygen for the treatment of carbon monoxide-induced delayed neurological sequelae: a case report and review of the literature. Diving and Hyperbaric Medicine. 2024 31 March;54(1):65−68. doi: 10.28920/dhm54.1.65-68. PMID: 38507912.)
Introduction: Hyperbaric oxygen treatment (HBOT) remains a recognised treatment for acute carbon monoxide (CO) poisoning, but the utility of HBOT in treating CO-induced delayed neurological sequelae (DNS) is not yet established.
Case description: A 26-year old woman presented with reduced consciousness secondary to CO exposure from burning charcoal. She underwent a single session of HBOT with US Navy Treatment Table 5 within six hours of presentation, with full neurological recovery. Eight weeks later, she represented with progressive, debilitating neurological symptoms mimicking Parkinsonism. Magnetic resonance imaging of her brain demonstrated changes consistent with hypoxic ischaemic encephalopathy. The patient underwent 20 sessions of HBOT at 203 kPa (2 atmospheres absolute) for 115 minutes, and received intravenous methylprednisolone 1 g per day for three days. The patient’s neurological symptoms completely resolved, and she returned to full-time professional work with no further recurrence.
Discussion: Delayed neurological sequelae is a well-described complication of CO poisoning. In this case, the patient’s debilitating neurocognitive symptoms resolved following HBOT. Existing literature on treatment of CO-induced DNS with HBOT consists mainly of small-scale studies and case reports, many of which similarly suggest that HBOT is effective in treating this complication. However, a large, randomised trial is required to adequately determine the effectiveness of HBOT in the treatment of CO-induced DNS, and an optimal treatment protocol.
Copyright: This article is the copyright of Case report
Diving Hyperb Med. 2024 31 March;54(1):69−72. doi: 10.28920/dhm54.1.69-72. PMID: 38507913.
The first deep rebreather dive using hydrogen: case report
Richard J Harris1, Craig J Challen1, Simon J Mitchell1,2,3,4
1 Technical diver, Wetmules Dive Team
2 Department of Anaesthesiology, School of Medicine, University of Auckland, Auckland, New Zealand
3 Department of Anaesthesia, Auckland City Hospital, Auckland, New Zealand
4 Slark Hyperbaric Unit, North Shore Hospital, Auckland, New Zealand
Corresponding author: Professor Simon Mitchell, Department of Anaesthesiology, School of Medicine, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
ORCiD: 0000-0002-5149-6371
Keywords
Helihydrox; High pressure neurological syndrome; HPNS; Hydreliox; Hydrox; Technical diving; Trimix
Abstract
(Harris RJ, Challen CJ, Mitchell SJ. The first deep rebreather dive using hydrogen: case report. Diving and Hyperbaric Medicine. 2024 31 March;54(1):69−72. doi: 10.28920/dhm54.1.69-72. PMID: 38507913.)
Bounce diving with rapid descents to very deep depths may provoke the high-pressure neurological syndrome (HPNS). The strategy of including small fractions of nitrogen in the respired gas to produce an anti-HPNS narcotic effect increases the gas density which may exceed recommended guidelines. In 2020 the ‘Wetmules’ dive team explored the Pearse Resurgence cave (New Zealand) to 245 m breathing trimix (approximately 4% oxygen, 91% helium and 5% nitrogen). Despite the presence of nitrogen, one diver experienced HPNS tremors beyond 200 m. The use of hydrogen (a light yet slightly narcotic gas) has been suggested as a solution to this problem but there are concerns, including the potential for ignition and explosion of hydrogen-containing gases, and accelerated heat loss. In February 2023 a single dive to 230 m was conducted in the Pearse Resurgence to experience hydrogen as a breathing gas in a deep bounce dive. Using an electronic closed-circuit rebreather, helihydrox (approximately 3% oxygen, 59% helium and 38% hydrogen) was breathed between 200 and 230 m. This was associated with amelioration of HPNS symptoms in the vulnerable diver and no obvious adverse effects. The use of hydrogen is a potential means of progressing deeper with effective HPNS amelioration while maintaining respired gas density within advised guidelines.
Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.
Publication Type: Case report
Diving Hyperb Med. 2024 March 31;54(1):73−74. doi: 10.28920/dhm54.1.73-74. PMID: 38507914.
Time to shock people
Gerard Laden1, Bruce Mathew1, Ananthakrishnan Ananthasayanam1,2
1 Clinical Hyperbaric Facility, Hull and East Riding Hospital, Anlaby, UK
2 Department of Surgery, Hull University Teaching Hospitals, NHS Trust, Hull, UK
Corresponding author: Mr Gerard Laden, Clinical Hyperbaric Facility, Hull and East Riding Hospital, Anlaby, UK
ORCiD: 0009-0008-0820-8291
Keywords
Cardiac; CPR, Defibrillation; First aid; Resuscitation
Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.
Publication Type: Letter to the Editor
Diving Hyperb Med. 2024 March 31;54(1):74−75. doi: 10.28920/dhm54.1.74-75. PMID: 38507915.
Response to Laden et al.
Andrew Tabner1,2, Graham Johnson1,2, Philip Bryson3 on behalf of the authorship team
1 Emergency Department, Royal Derby Hospital, Uttoxeter Road, Derby, UK, DE22 3NE
2 University of Nottingham Medical School, Queen’s Medical Centre, Nottingham, UK, NG7 2UH
3 TAC Healthcare, Wellheads Crescent, Aberdeen, Scotland AB21 7GA
Corresponding author: Dr Andrew Tabner, Emergency Department, Royal Derby Hospital, Uttoxeter Road, Derby, UK, DE22 3NE
Keywords
Resuscitation; Defibrillation; Mechanical CPR; Cardiovascular; Letters (to the Editor)
Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.
Publication Type: Letter to the Editor