2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):2–8. doi: 10.28920/dhm50.1.2-8. PMID: 32187611. PMCID: PMC7276273.
Assessment of pulmonary oxygen toxicity in special operations forces divers under operational circumstances using exhaled breath analysis
Thijs T Wingelaar1,2, Paul Brinkman3, Rigo Hoencamp4,5,6, Pieter-Jan AM van Ooij1,3, Anke-Hilse Maitland-van der Zee3, Markus W Hollmann2, Rob A van Hulst2
1 Diving Medical Centre, Royal Netherlands Navy, Den Helder, the Netherlands
2 Department of Anesthesiology, Amsterdam University Medical Centre, location AMC, Amsterdam, the Netherlands
3 Department of Pulmonology, Amsterdam University Medical Centre, location AMC, Amsterdam, the Netherlands
4 Department of Surgery, Alrijne Hospital, Leiderdorp, the Netherlands
5 Defence Healthcare Organisation, Ministry of Defence, Utrecht, the Netherlands
6 Leiden University Medical Centre, Leiden, the Netherlands
Corresponding author: Dr Thijs T Wingelaar, Royal Netherlands Navy Diving Medical Centre, Rijkszee en marinehaven,
1780 CA, Den Helder, the Netherlands
Key words
Volatile organic compounds; VOCs; Gas chromatography-mass spectrometry; GC-MS; Methyl alkanes; Oxygen rebreather diving; O2-CCR
Abstract
(Wingelaar TT, Brinkman P, Hoencamp R, van Ooij PJAM, Maitland-van der Zee AH, Hollmann MW, van Hulst RA. Assessment of pulmonary oxygen toxicity in special operations forces divers under operational circumstances using exhaled breath analysis. Diving and Hyperbaric Medicine. 2020 March 31;50(1):2–8. doi: 10.28920/dhm50.1.2-8. PMID: 32187611. PMCID: PMC7276273.)
Introduction: The Netherlands Maritime Special Operations Forces use closed circuit oxygen rebreathers (O2-CCR), which can cause pulmonary oxygen toxicity (POT). Recent studies demonstrated that volatile organic compounds (VOCs) can be used to detect POT in laboratory conditions. It is unclear if similar VOCs can be identified outside the laboratory. This study hypothesised that similar VOCs can be identified after O2-CCR diving in operational settings.
Methods: Scenario one: 4 h O2-CCR dive to 3 metres’ seawater (msw) with rested divers. Scenario two: 3 h O2-CCR dive to 3 msw following a 5 day physically straining operational scenario. Exhaled breath samples were collected 30 min before and 30 min and 2 h after diving under field conditions and analysed using gas chromatography-mass spectrometry (GC-MS) to reconstruct VOCs, whose levels were tested longitudinally using a Kruskal-Wallis test.
Results: Eleven divers were included: four in scenario one and seven in scenario two. The 2 h post-dive sample could not be obtained in scenario two; therefore, 26 samples were collected. GC-MS analysis identified three relevant VOCs: cyclohexane, 2,4-dimethylhexane and 3-methylnonane. The intensities of 2,4-dimethylhexane and 3-methylnonane were significantly (P = 0.048 and P = 0.016, respectively) increased post-dive relative to baseline (range: 212–461%) in both scenarios. Cyclohexane was increased not significantly (P = 0.178) post-dive (range: 87–433%).
Conclusions: VOCs similar to those associated with POT in laboratory conditions were identified after operational O2-CCR dives using GC-MS. Post-dive intensities were higher than in previous studies, and it remains to be determined if this is attributable to different dive profiles, diving equipment or other environmental factors.
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
Full article available here.
2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):9–16. doi: 10.28920/dhm50.1.9-16. PMID: 32187612. PMCID: PMC7276269.
Factors influencing the severity of long-term sequelae in fishermen divers with neurological decompression sickness
Jean-Eric Blatteau1, Kate Lambrechts2, Jean Ruffez3
1 Department of Diving and Hyperbaric Medicine, Sainte-Anne Military Hospital, Toulon, France
2 Environmental Occupational and Ageing Physiology Laboratory, Haute Ecole Bruxelles-Brabant, Brussels, Belgium
3 Program of Assistance to Vietnamese Fishermen Divers, Association Francophone d’Entraide et de Promotion des Sciences de la Vie, Section Paris, Ile de France, Maison des Associations du XIe, France
Corresponding author: Professor Jean-Eric Blatteau, Service de Médecine Hyperbare et d’Expertise Plongée (SMHEP), Hôpital d’Instruction des Armées Sainte-Anne, 2 boulevard Sainte-Anne, BP 600 Toulon cédex 9, France
Key words
Diving; Bubbles; Decompression sickness; Fisherman diver; Neurologic sequelae; Hyperbaric oxygen; In-water recompression
Abstract
(Blatteau JE, Lambrechts K, Ruffez J. Factors influencing the severity of long-term sequelae in fishermen-divers with neurological decompression sickness. Diving and Hyperbaric Medicine. 2020 March 31;50(1):9–16. doi: 10.28920/dhm50.1.9-16. PMID: 32187612. PMCID: PMC7276269.)
Introduction: Numerous studies have been conducted to identify the factors influencing the short-term prognosis for neurological decompression sickness (DCS). However, the long-term sequelae are rarely assessed. The purpose of this study to investigate the factors likely to influence the long-term prognosis.
Methods: Twenty-seven Vietnamese fishermen-divers who on average 9 (SD 6) years beforehand had presented with neurological DCS and ongoing sequelae, were questioned and examined. The severity of the initial clinical profile was quantified using a severity score. The long-term sequelae were clinically evaluated by looking for a motor or sensory deficit or muscular spasticity, and by applying a severity score for the sequelae which focussed on gait and sphincter disorders.
Results: An initial severity score of ≥ 15 is significantly associated with a risk of serious long-term sequelae [OR = 13.7 (95% CI 2.4 to 79.5)]. Furthermore, certain treatment practices such as in-water recompression to depths > 17 metres’ seawater breathing air are significantly associated with more serious sequelae. The practice of intensive non-standardised hyperbaric oxygen sessions over prolonged durations (median 30 days [IQR 19.5]) delayed after the initial accident (median 4 days [IQR 6]) also seems unfavourable.
Conclusion: This study establishes a link between the initial DCS severity and the long-term sequelae causing severe gait disorders and sphincter incontinence. Furthermore, this work suggests that certain detrimental treatment practices should be modified. During this field study, we also found that it was possible to reduce sequelae of these divers by offering them an individual programme of self-rehabilitation.
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
Full article available here.
2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):17–23. doi: 10.28920/dhm50.1.17-23. PMID: 32187613. PMCID: PMC7276266.
Measurement of peripheral arterial tonometry in patients with diabetic foot ulcers during courses of hyperbaric oxygen treatment
Morten Hedetoft1, Niels V Olsen1, Isabel G Smidt-Nielsen1, Anna M Wahl1, Anita Bergström2, Anders Juul3,4, Ole Hyldegaard1,3
1 The Hyperbaric Oxygen Treatment Unit, Department of Anaesthesia, Centre of Head and Orthopaedics, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
2 Center for Functional and Diagnostic Imaging and Research, Hvidovre Hospital, University of Copenhagen, Denmark
3 Department of Clinical Medicine, University of Copenhagen, Denmark
4 Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Denmark
Corresponding author: Dr Morten Hedetoft, The Hyperbaric Oxygen Treatment Unit, Department of Anaesthesia, Centre of Head and Orthopaedics, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
Key words
Endothelium; Diabetes; Hyperbaric Research; Wounds
Abstract
(Hedetoft M, Olsen NV, Smidt-Nielsen IG, Wahl AM, Bergström A, Juul A, Hyldegaard O. Measurement of peripheral arterial tonometry in patients with diabetic foot ulcers during courses of hyperbaric oxygen treatment. Diving and Hyperbaric Medicine. 2020 March 31;50(1):17–23. doi: 10.28920/dhm50.1.17-23. PMID: 32187613. PMCID: PMC7276266.)
Introduction: Treatment of diabetic foot ulcers is complex and often protracted. Hyperbaric oxygen treatment (HBOT) improves wound healing in diabetic ulcers and serves as an important adjunct to regular diabetic wound care. Endothelial dysfunction plays a central role in diabetes-related vascular complications and may be evaluated by a non-invasive technique called peripheral arterial tonometry which measures a reactive hyperaemia index (RHI). We hypothesized that endothelial function measured by peripheral arterial tonometry is impaired in diabetic foot ulcer patients and that HBOT might improve endothelial function.
Methods: Endothelial function was prospectively assessed by peripheral arterial tonometry in 22 subjects with diabetic foot ulcers and 17 subjects without diabetes during courses of HBOT. Endothelial function was evaluated before first (baseline) and 30th treatments, and at 90-day follow-up. Serum insulin growth factor-I (IGF-I) concentrations were determined by immunoassay. Results were compared to 23 healthy subjects.
Results: No baseline differences were found in endothelial function between subjects with diabetes, HBOT patients without-diabetes and healthy control subjects (RHI; 1.26, 1.61 and 1.81, respectively). No significant changes in RHI were found in patients with (P = 0.17) or without (P = 0.30) diabetes during courses of HBOT. At 90-day follow-up IGF-I was significantly reduced in the subjects with diabetes (P = 0.001) and unchanged in the group without diabetes (P = 0.99).
Conclusions: We found no significant differences in RHI between subjects with diabetic foot ulcers and patients without diabetes, nor improvement in endothelial function assessed by peripheral arterial tonometry during courses of HBOT.
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
Full article available here.
2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):24–27. doi: 10.28920/dhm50.1.24-27. PMID: 32187614. PMCID: PMC7276274.
Haemoconcentration, not decreased blood temperature, increases blood viscosity during cold water immersion
Kaitlyn A Rostomily1, Douglas M Jones1, Carina M Pautz1, Danica W Ito1, Michael J Buono1
1 San Diego State University, San Diego CA, USA
Corresponding author: Dr Michael J Buono, MC-7251, San Diego State University, San Diego, CA 92182, USA
Key words
Blood viscosity; Cold; Hemoconcentration; Hypothermia; Ice; Physiology; Stress
Abstract
(Rostomily KA, Jones DM, Pautz CM, Ito DW, Buono MJ. Haemoconcentration, not decreased blood temperature, increases blood viscosity during cold water immersion. Diving and Hyperbaric Medicine. 2020 March 31;50(1):24–27. doi: 10.28920/dhm50.1.24-27. PMID: 32187614. PMCID: PMC7276274.)
Introduction: Prolonged cold-water immersion (CWI) has the potential to cause significant hypothermia and haemoconcentration; both of which have previously been shown to independently increase blood viscosity in vitro. The purpose of this study was to determine the effect of CWI on blood viscosity and examine the relative contribution of decreased blood temperature and haemoconcentration.
Methods: Ten healthy volunteers were immersed to mid-sternum in 10°C water for 90 minutes. Gastrointestinal (GI) temperature, haematocrit (Hct), and blood viscosity were measured pre- and post-CWI.
Results: CWI caused mean (SD) GI temperature to decrease from 37.5 (0.3)°C to 36.2 (0.7)°C (P < 0.05). CWI also caused mean Hct to increase from 40.0 (3.5)% to 45.0 (2.9)% (P < 0.05). As a result of the haemoconcentration and decreased GI temperature during CWI the mean blood viscosity increased by 19% from 2.80 (0.28) mPa·s-1 to 3.33 (0.42) mPa·s-1 (P < 0.05). However, when the pre-CWI blood sample was measured at the post-CWI GI temperature (36.2°C) there was no significant difference in the blood viscosity when compared to the pre-CWI (37.5°C) blood sample (2.82 (0.20) mPa·s-1 and 2.80 (0.28) mPa·s-1 respectively). Furthermore, the changes in Hct and blood viscosity during CWI were significantly correlated with an r = 0.84.
Conclusion: The results of the current study show that prolonged, severe CWI causes a significant 19% increase in blood viscosity. In addition, the results strongly suggest that almost all of the increased blood viscosity seen following CWI is the result of haemoconcentration, not decreased blood temperature.
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
Full article available here.
2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):28–33. doi: 10.28920/dhm50.1.28-33. PMID: 32187615. PMCID: PMC7276272.
Professional diver routine health surveillance and certification: an internet-based satisfaction survey of New Zealand divers
Chris Sames1, Des F Gorman2, Simon J Mitchell1,3,4, Lifeng Zhou5
1 Slark Hyperbaric Unit, Waitemata District Health Board, Auckland, New Zealand
2 Department of Medicine, University of Auckland, Auckland, New Zealand
3 Department of Anaesthesiology, University of Auckland, Auckland, New Zealand
4 Department of Anaesthesia, Auckland City Hospital, Auckland, New Zealand
5 Planning, funding and outcomes, Waitemata and Auckland District Health Boards, Auckland, New Zealand
Corresponding author: Dr Chris Sames, Slark Hyperbaric Unit, PO Box 32051, Devonport, Auckland, New Zealand
Key words
Diving industry; Fitness to dive; Health surveillance; Medicals – diving; Occupational diving; Occupational health; Survey
Abstract
(Sames C, Gorman DF, Mitchell SJ, Zhou L. Professional diver routine health surveillance and certification: an internet-based satisfaction survey of New Zealand divers. Diving and Hyperbaric Medicine. 2020 March 31;50(1):28–33. doi: 10.28920/dhm50.1.28-33. PMID: 32187615. PMCID: PMC7276272.)
Introduction: Professional divers, like many other specialised occupational groups, are subject to regulatory constraints that include mandatory initial medical certification and routine recertification. The New Zealand system of diver certification and health surveillance has undergone modifications in recent years, but its acceptance among end-users has never been formally assessed. Because of the wide variety of tasks, circumstances and personalities encountered in the diving industry, unanimous satisfaction is an unrealistic expectation, but establishing the current mood of divers in this regard and canvassing opinions on possible improvements is an important step towards optimising the certification process.
Method: A multi-choice satisfaction questionnaire was added, as a quality assurance measure, to the on-line health questionnaire completed annually by all New Zealand professional divers. A complete 12-month dataset was analysed to determine levels of satisfaction, areas of dissatisfaction and suggestions for improvement. Comparison of the opinions of various diver groups was achieved by stratification into employment-type sub-groups and those working locally, overseas or both.
Results: The responses of 914 divers who completed the survey established an 85% satisfaction rate with the existing diver certification system. Dissatisfaction was independent of diving locality. Compliance cost was the most common area of dissatisfaction, particularly among recreational diving instructors.
Conclusions: Most New Zealand professional divers consider the current certification system satisfactory. Effective communication between the regulating authority and divers was identified as an important area for further development.
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
Full article available here.
2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):34–42. doi: 10.28920/dhm50.1.34-42. PMID: 32187616. PMCID: PMC7276271.
Comparison of tissue oxygenation achieved breathing oxygen using different delivery devices and flow rates
Denise F Blake1,2, Melissa Crowe3, Daniel Lindsay4, Annie Brouff 5, Simon J Mitchell6,7, Peter A Leggat4, Neal W Pollock8,9
1 Emergency Department, The Townsville Hospital, Townsville, Queensland, Australia
2 Marine Biology and Aquaculture, James Cook University, Townsville, Queensland, Australia
3 Sport and Exercise Science, James Cook University, Townsville, Queensland, Australia
4 College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland, Australia
5 Hyperbaric Medicine Unit, The Townsville Hospital, Townsville, Queensland, Australia
6 Department of Anaesthesiology, University of Auckland, Auckland, New Zealand
7 Department of Anaesthesia, Auckland City Hospital, Auckland, New Zealand
8 Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
9 Service de médecine hyperbare, Centre de médecine de plongée du Québec, Levis, Québec, Canada
Corresponding author: Dr Denise Blake, IMB 23, Emergency Department, The Townsville Hospital, 100 Angus Smith
Drive, Douglas, Queensland Australia, 4814
Key words
Decompression sickness; Decompression illness; First aid; Masks; Medical kits; Oxygen; Transcutaneous oximetry; Scuba diving
Abstract
(Blake DF, Crowe M, Lindsay D, Brouff A, Mitchell SJ, Leggat PA, Pollock NW. Comparison of tissue oxygenation achieved breathing oxygen using different delivery devices and flow rates. Diving and Hyperbaric Medicine. 2020 March 31;50(1):34–42. doi: 10.28920/dhm50.1.34-42. PMID: 32187616. PMCID: PMC7276271.)
Introduction: Divers with suspected decompression illness require high concentration oxygen (O2). There are many different O2 delivery devices, with few data comparing their performance. This study evaluated O2 delivery, using tissue O2 partial pressure (PtcO2), in healthy divers breathing O2 via three different delivery devices.
Methods: Twelve divers had PtcO2 measured at six limb sites. Participants breathed O2 from: a demand valve using an intraoral mask with a nose clip (NC); a medical O2 rebreathing system (MORS) with an oronasal mask and with an intraoral mask; and a non-rebreather mask (NRB) at 15 or 10 L·min-1 O2 flow. In-line inspired O2 (FIO2) and nasopharyngeal FIO2 were measured. Participants provided subjective ratings of device comfort, ease of breathing, and overall ease of use.
Results: PtcO2 values and nasopharyngeal FIO2 were similar with the demand valve with intraoral mask, MORS with both masks and the NRB at 15 L·min-1. PtcO2 and nasopharyngeal FIO2 values were significantly lower with the NRB at 10 L·min-1. The NRB was rated as the most comfortable to wear, easiest to breathe with, and overall the easiest to use.
Conclusion: Of the commonly available devices promoted for O2 delivery to injured divers, similar PtcO2 and nasopharyngeal FIO2 values were obtained with the three devices tested: MORS with an oronasal or intraoral mask, demand valve with an intraoral mask and NRB at a flow rate of 15 L·min-1. PtcO2 and nasopharyngeal FIO2 values were significantly lower when the flow rate using the NRB was decreased to 10 L·min-1.
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
Full article available here.
2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):43–48. doi: 10.28920/dhm50.1.43-48. PMID: 32187617. PMCID: PMC7276270.
Manned validation of a US Navy Diving Manual, Revision 7, VVal-79 schedule for short bottom time, deep air decompression diving
Brian T Andrew1, David J Doolette1
1 Navy Experimental Diving Unit, Panama City Beach, Florida, USA
Corresponding author: Dr Brian T Andrew, Navy Experimental Diving Unit, 321 Bullfinch RD, Panama City Beach, Florida, USA
Key words
Military diving; Decompression sickness; Decompression illness; Decompression tables; Diving research; Echocardiography; Venous gas emboli
Abstract
(Andrew BT, Doolette DJ. Manned validation of a US Navy Diving Manual, Revision 7, VVal-79 schedule for short bottom time, deep air decompression diving. Diving and Hyperbaric Medicine. 2020 March 31;50(1):43–48. doi: 10.28920/dhm50.1.43-48. PMID: 32187617. PMCID: PMC7276270.)
Introduction: The US Navy air decompression table was promulgated in 2008, and a revised version, calculated with the VVal-79 Thalmann algorithm, was promulgated in 2016. The Swedish Armed Forces conducted a laboratory dive trial using the 2008 air decompression table and 32 dives to 40 metres' seawater for 20 minutes bottom time resulted in two cases of decompression sickness (DCS) and high venous gas emboli (VGE) grades. These results motivated an examination of current US Navy air decompression schedules.
Methods: An air decompression schedule to 132 feet seawater (fsw; 506 kPa) for 20 minutes bottom time with a 9-minute stop at 20 fsw was computed with the VVal-79 Thalmann algorithm. Dives were conducted in 29°C water in the ocean simulation facility at the Navy Experimental Diving Unit. Divers dressed in shorts and t-shirts performed approximately 90 watts cycle ergometer work on the bottom and rested during decompression. VGE were monitored with 2-D echocardiography at 20-minute intervals for two hours post-dive.
Results: Ninety-six man-dives were completed, resulting in no cases of DCS. The median (IQR) peak VGE grades were 3 (2–3) at rest and 3 (3–3) with limb flexion. VGE grades remained elevated two hours post-dive with median grades 1 (1–3) at rest and 3 (1–3) with movement.
Conclusions: Testing of a short, deep air decompression schedule computed with the VVal-79 Thalmann algorithm, tested under diving conditions similar to earlier US Navy dive trials, resulted in a low incidence of DCS.
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
Full article available here.
2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):49–53. doi: 10.28920/dhm50.1.49-53. PMID: 32187618. PMCID: PMC7276276.
Diving with hypertension and antihypertensive drugs
Peter E Westerweel1,2, Rienk Rienks2,3,4,5, Ahmed Sakr6, Adel Taher6
1 Department of Internal Medicine, Albert Schweitzer Hospital, Dordrecht, the Netherlands
2 Dutch Society for Diving Medicine
3 Central Military Hospital, Utrecht, the Netherlands
4 Military Hospital 'Queen Astrid', Brussels, Belgium
5 CardioExpert Outpatient Clinic, Amsterdam, the Netherlands
6 Hyperbaric Medical Center of Sharm el Sheikh and Dahab, Egypt
Corresponding author: Dr Peter E Westerweel, Albert Schweitzer Hospital, Department of Internal Medicine, Albert Schweitzerplaats 25, 3318 AT Dordrecht, the Netherlands
Key words
Diving medicine; Hypertension; Drugs; Fitness to Dive; Medicals – diving
Abstract
(Westerweel PE, Rienks R, Sakr A, Taher A. Diving with hypertension and antihypertensive drugs. Diving and Hyperbaric Medicine. 2020 March 31;50(1):49–53. doi: 10.28920/dhm50.1.49-53. PMID: 32187618. PMCID: PMC7276276.)
Hypertension is a common condition, which is highly prevalent amongst scuba divers. As a consequence, a substantial proportion of divers are hypertensive and/or on antihypertensive drugs when diving. In this article, we review available literature on the possible risks of diving in the presence of hypertension and antihypertensive drugs. Guidelines are presented for the diving physician for the selection of divers with hypertension suitable for diving, along with advice on antihypertensive treatment best compatible with scuba diving.
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
Full article available here.
2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):54–65. doi: 10.28920/dhm50.1.54-65. PMID: 32187619. PMCID: PMC7276267.
The current use of wearable sensors to enhance safety and performance in breath-hold diving: A systematic review
Giovanni Vinetti1,2, Nicola F Lopomo2, Anna Taboni3, Nazzareno Fagoni1, Guido Ferretti1,3
1 Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
2 Department of Information Engineering, University of Brescia, Brescia, Italy
3 Department of Anesthesiology, Pharmacology, Intensive Care and Emergencies, University of Geneva, Geneva, Switzerland
Corresponding author: Dr Giovanni Vinetti, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11–25123, Brescia, Italy
Key words
Physiology; Patient monitoring; Telemetry; Computers; Equipment; Training
Abstract
(Vinetti G, Lopomo NF, Taboni A, Fagoni N, Ferretti G. The current use of wearable sensors to enhance safety and performance in breath-hold diving: A systematic review. Diving and Hyperbaric Medicine. 2020 March 31;50(1):54–65. doi: 10.28920/dhm50.1.54-65. PMID: 32187619. PMCID: PMC7276267.)
Introduction: Measuring physiological parameters at depth is an emergent challenge for athletic training, diver’s safety and biomedical research. Recent advances in wearable sensor technology made this challenge affordable; however, its impact on breath-hold diving has never been comprehensively discussed.
Methods: We performed a systematic review of the literature in order to assess what types of sensors are available or suitable for human breath-hold diving, within the two-fold perspective of safety and athletic performance.
Results: In the 52 studies identified, sensed physiological variables were: electrocardiogram, body temperature, blood pressure, peripheral oxygen saturation, interstitial glucose concentration, impedance cardiography, heart rate, body segment inertia and orientation.
Conclusions: Limits and potential of each technology are separately reviewed. Inertial sensor technology and transmission pulse oximetry could produce the greatest impact on breath-hold diving performances in the future.
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: Reviewl article
Full article available here.
2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):66–69. doi: 10.28920/dhm50.1.66-69. PMID: 32187620. PMCID: PMC7276275.
Pulmonary barotrauma: a case report with illustrative radiology
Sarah Bigeni1, Mario Saliba1
1 Hyperbaric Unit, Gozo General Hospital, Malta
Corresponding author: Dr Sarah Bigeni, Medical Consultant, Hyperbaric Unit, Gozo General Hospital, Ghajn Qatet Street, Victoria VCT2520, Malta
Key words
Pulmonary barotrauma; Diving; Pneumothorax; CT scan
Abstract
(Bigeni S, Saliba M. Pulmonary barotrauma: a case report with illustrative radiology. Diving and Hyperbaric Medicine. 2020 March 31;50(1):66–69. doi: 10.28920/dhm50.1.66-69. PMID: 32187620. PMCID: PMC7276275.)
A case of a 24-year-old gentleman who had pulmonary barotrauma (PBT) after diving is reported. He presented with chest pain after the second of two uneventful shallow SCUBA dives. Computerized tomography (CT) scan confirmed the diagnosis and he was treated conservatively. Relevant radiology and a discussion of PBT are presented.
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
Ful article available here.
2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):70–74. doi: 10.28920/dhm50.1.70-74. PMID: 32187621. PMCID: PMC7276268.
Symptoms of central nervous system oxygen toxicity during 100% oxygen breathing at normobaric pressure with increasing inspired levels of carbon dioxide: a case report
Mirit Eynan1,2, Yehuda Arieli1,2, Boris Taran3, Yoav Yanir4
1 Israel Naval Medical Institute, Israel Defense Forces Medical Corps, Haifa, Israel
2 Department of Military Medicine, Hebrew University, Jerusalem, Israel
3 Israel Navy Medical Branch, Israel Defense Forces Medical Corps, Haifa, Israel
4 Department of Otolaryngology-Head and Neck Surgery, Carmel Medical Center, Haifa, Israel
Corresponding author: Dr Mirit Eynan, The Israel Naval Medical Institute (INMI), Box 22, Rambam Health Care Campus, P.O. Box 9602, 3109601 Haifa, Israel
Key words
Case reports; Carbon dioxide; Diving; Diving medicine; Hypercapnia; Oxygen; Pressure
Abstract
(Eynan M, Arieli Y, Taran B, Yanir Y. Symptoms of CNS-oxygen toxicity during 100% oxygen breathing at normobaric pressure with increasing inspired levels of carbon dioxide: a case report. Diving and Hyperbaric Medicine. 2020 March 31;50(1):70–74. doi: 10.28920/dhm50.1.70-74. PMID: 32187621. PMCID: PMC7276268.)
The greatest danger faced by divers who use oxygen-enriched gas mixtures is central nervous system oxygen toxicity (CNS-OT). CNS-OT is characterised by convulsions resembling grand-mal epileptic seizures, which may terminate in drowning and death. Elevated arterial levels of carbon dioxide (CO2) (hypercapnia) represent a major risk factor for CNS-OT when breathing hyperoxic gas mixtures. To reduce the risk of a diver being involved in a CNS-OT incident due to hypercapnia, candidates for combat diving are examined at our institute using a routine physiological training procedure, in which they are tested for CO2 detection and retention. We present the case of a candidate for combat diving, who unexpectedly exhibited signs typical of CNS-OT while breathing pure oxygen under normobaric conditions with > 3 kPa inspired CO2. Severe headache and nausea, as well as facial muscle twitching, appeared during one of these routine tests. Subsequent medical examination including neurological tests, magnetic resonance imaging and an electroencephalogram were unremarkable. To the best of our knowledge, an event such as this has never previously been published in the medical literature. We present a discussion of the case, and a review of the relevant literature regarding CO2 as a risk factor for the development of CNS-OT.
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
Full article available here.
2020 March;50(1)
Diving Hyperb Med. 2020 March 31;50(1):75–76. doi: 10.28920/dhm50.1.75-76. PMID: 32187622. PMCID: PMC7276277.
Effect of an air break on the occurrence of seizures in hyperbaric oxygen therapy may be predicted by the power equation for hyperoxia at rest
Ran Arieli
The Israel Naval Medical Institute, Israel, Defence Forces Medical Corps, Haifa, Israel; Eliachar, Research Laboratory, Western Galilee Medical Centre, Nahariya, Israel
Address for correspondence: Dr Ran Arieli, 12 Klil-Hakhoresh, Rakefet, D.N. Misgav 2017500, Israel
Key words
CNS Oxygen toxicity; Recovery; Resting conditions; Prediction; Letter (to the editor)
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Publication Type: Letter to the Editor
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