2019 March;49(1)
Diving Hyperb Med. 2019 March;49(1):2−8. doi: 10.28920/dhm49.1.2-8. PMID: 30856661. PMCID: PMC6526056.
The impact of diving on hearing: a 10–25 year audit of New Zealand professional divers
Chris Sames1, Desmond F Gorman1,2, Simon J Mitchell1,3, Lifeng Zhou4
1 Slark Hyperbaric Unit, Waitemata District Health Board, Auckland, New Zealand
2 Department of Medicine, University of Auckland, Auckland
3 Department of Anaesthesiology, University of Auckland
4 Health Funding and Outcomes, Waitemata and Auckland District Health Boards, Auckland
Corresponding author: Chris Sames, Slark Hyperbaric Unit, Waitemata District Health Board, PO Box 32051, Devonport, Auckland 0744, New Zealand
Key words
Audiology; Fitness to dive; Hearing loss; Medicals – diving; Occupational diving; Surveillance
Abstract
(Sames C, Gorman DF, Mitchell SJ, Zhou L. The impact of diving on hearing: a 10–25 year audit of New Zealand professional divers. Diving and Hyperbaric Medicine. 2019 March 31;49(1):2–8. doi: 10.28920/dhm49.1.2-8. PMID: 30856661. PMCID: PMC6526056.)
Introduction: Surveillance of professional divers’ hearing is routinely undertaken on an annual basis despite lack of evidence of benefit to the diver. The aim of this study was to determine the magnitude and significance of changes in auditory function over a 10−25 year period of occupational diving with the intention of informing future health surveillance policy for professional divers.
Methods: All divers with adequate audiological records spanning at least 10 years were identified from the New Zealand occupational diver database. Changes in auditory function over time were compared with internationally accepted normative values. Any significant changes were tested for correlation with diving exposure, smoking history and body mass index.
Results: The audiological records of 227 professional divers were analysed for periods ranging from 10 to 25 years. Initial hearing was poorer than population norms, and deterioration over the observation period was less than that predicted by normative data. Changes in hearing were not related to diving exposure, or smoking history.
Conclusion: Audiological changes over 10 to 25 years of occupational diving were not found to be significantly different from age-related changes. Routine annual audiological testing of professional divers does not appear to be justifiable.
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.
2019 March;49(1)
Diving Hyperb Med. 2019 March;49(1):9−15. doi: 10.28920/dhm49.1.9-15. PMID: 30856662. PMCID: PMC6526055.
Eustachian tube balloon dilation in treatment of equalization problems of freediving spearfishermen
Antonio AM Giunta1, Luca Liberati1, Cristina Pellegrino1, Giampietro Ricci2, Santino Rizzo1
1 ENT Department of Santa Maria Hospital of Terni, Viale Tristano di Joannuccio, Terni, Italy
2 ENT Department of Santa Maria della Misericordia of Perugia, Piazza Menghini 1, Perugia, Italy
Corresponding author: Antonio Alberto Maria Giunta, ENT Department of Santa Maria Hospital of Terni, Viale Tristano di Joannuccio, Terni, Italy
Key words
ENT; Ear barotrauma; Diving; Treatment; Outcome
Abstract
(Giunta AAM, Liberati L, Pellegrino C, Ricci G, Rizzo S. Eustachian tube balloon dilation in treatment of equalization problems of freediving spearfishermen. Diving and Hyperbaric Medicine. 2019 March 31;49(1):9–15. doi: 10.28920/dhm49.1.9-15. PMID: 30856662. PMCID: PMC6526055.)
Background: Eustachian tube balloon dilation is a minimally invasive surgical procedure used to treat Eustachian tube dysfunction which is not responsive to conventional therapies.
Methods: In this cohort intervention series we report the results of balloon dilation in treating refractory equalization problems in 20 freediving spearfishermen; in 19 cases the problem was unilateral and in one case bilateral. All the patients had already received medical and insufflation therapy and four patients had also had nasal surgery. None of these treatments or procedures had achieved improvement. We used a 20 mm x 3 mm disposable balloon catheter inserted through a 70-degree guide catheter and inflated up to 12 ATM three times at three different depths of insertion within the Eustachian tube. Every inflation lasted 120 seconds.
Results: Fifteen out of 20 patients improved. Ten patients reported a complete resolution of equalization problems, five showed improvement with persistence of a slight equalization delay on the treated side. Five patients did not report any improvement. Two complications occurred: subcutaneous emphysema of the parotid region in one case; and a mild high frequency (4–8 KHz) sensorineural hearing loss in another patient.
Conclusion: Balloon dilation of the Eustachian tube is an effective therapy in the treatment of equalization problems with a good success rate.
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.
2019 March;49(1)
Diving Hyperb Med. 2019 March;49(1):16−20. doi: 10.28920/dhm49.1.16-20. PMID: 30856663. PMCID: PMC6526054.
The effects of pressure in vitro on three methods of root canal obturation
Pooria Safai1, Babak Farzaneh1, Reza Fekrazad2,3
1 Department of Endodontics, Faculty of Dentistry, AJA University of Medical Sciences, Tehran, Iran
2 Department of Periodontology, Dental Faculty - Laser Research Center in Medical Sciences, AJA University of Medical Sciences, Tehran
3 International Network for Photo Medicine and Photo Dynamic Therapy (INPMPDT), Universal Scientific Education and Research Network (USERN), Tehran
Corresponding author: Babak Farzaneh, Department of Endodontics, Faculty of Dentistry, AJA University of Medical Sciences, Tehran, Iran
Key words
Barotrauma; Dental; Diving; Endodontics
Abstract
(Safai P, Farzaneh B, Fekrazad R. The effects of pressure in vitro on three methods of root canal obturation. Diving and Hyperbaric Medicine. 2019 March 31;49(1):16–20. doi: 10.28920/dhm49.1.16-20. PMID: 30856663. PMCID: PMC6526054.)
Introduction: The seal of root canal fillings depends on the anatomy of the root canal system and on the properties of filling materials and their bond to the walls of the root canal. Alterations in pressure may influence these properties. The current study investigated and compared microleakage in a tapered single-cone method versus lateral and vertical condensation after diving simulation.
Methods: One hundred and thirty five extracted single-rooted teeth were used. Following instrumentation and irrigation to #30.06 Mtwo rotary system, obturations were performed in three groups of 45 teeth: Group 1, tapered single-cone with Endoseal MTA sealer; Group 2, lateral condensation with AH26 sealer; Group 3, vertical condensation with AH26 sealer. Then all specimens were divided into three groups and incubated at ambient room pressure (101.3 kPa), 203 kPa or 304 kPa for 120 minutes respectively 20 times over one month to simulate diving conditions. Microleakage quantitative analysis was recorded by using a 2% Methylene blue dye for 24 hours.
Results: The amounts of microleakage increased with increasing pressure in all obturation groups; however, the differences were not statistically significant (P > 0.05). At all three pressures, the least microleakage was recorded in Group 3, vertical condensation. Although the differences between vertical condensation, lateral condensation, and tapered single-cone methods were statistically significant (P < 0.001), the vertical condensation and lateral condensation groups did not differ from each other (P > 0.05).
Conclusions: Vertical condensation may be the best technique, based on sealing ability, for people who frequently experience pressure alterations.
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.
2019 March;49(1)
Diving Hyperb Med. 2019 March;49(1):21−29. doi: 10.28920/dhm49.1.21-29. PMID: 30856664. PMCID: PMC6526051.
A 20-year analysis of compressed gas diving-related deaths in Tasmania, Australia
Juan Carlos Ascencio-Lane1, David Smart1,2, John Lippmann3,4
1 Department of Diving and Hyperbaric Medicine, Royal Hobart Hospital, Hobart, Tasmania, Australia
2 School of Medicine, University of Tasmania, Hobart
3 Divers Alert Network (DAN) Asia-Pacific, Ashburton,Victoria, Australia
4 Department of Public Health and Preventative Medicine at Monash University, Melbourne, Victoria
Corresponding author: Juan Carlos Ascencio-Lane, Department of Diving and Hyperbaric Medicine, Royal Hobart Hospital, GPO Box 1061, Hobart, Tasmania 7001, Australia
Key words
Diving deaths; Diving incidents; Incidents; Risk management; Root-cause analysis; Safety; Case reports
Abstract
(Ascencio-Lane JC, Smart D, Lippmann J. A twenty-year analysis of compressed gas diving-related deaths in Tasmania. Diving and Hyperbaric Medicine. 2019 March 31;49(1):21–29. doi: 10.28920/dhm49.1.21-29. PMID: 30856664. PMCID: PMC6526051.)
Introduction: This study reviews diving deaths that occurred in Tasmanian waters over a 20-year period.
Methods: Detailed analysis was undertaken of deaths that occurred from 01 January 1995 to 31 December 2014. The cases were collated from numerous sources. Utilising a chain of events analysis, factors were identified and assigned to predisposing factors, triggers, disabling agents, disabling injuries and cause of death. These were then scrutinised to ascertain regional variables, remediable factors and linkages which may benefit from targeted risk mitigation strategies.
Results: Seventeen deaths were identified across this 20-year period, which included one additional case not previously recorded. All were recreational divers and 15 were male. Five were hookah divers, 12 were scuba divers. Important predisposing factors identified included equipment (condition and maintenance), pre-existing health conditions, diver experience and training. These factors can now be used to promote public health messages for divers.
Conclusions: This 20-year study highlighted regional variations for Tasmanian deaths and presents opportunities for strategies to prevent diving deaths in the future. Of particular concern was the diving practice of ‘hookah’ diving, which has no governing regulations. The study highlighted the importance of applying a structured methodology such as chain of events analysis to scrutinise diving deaths.
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.
2019 March;49(1)
Diving Hyperb Med. 2019 March;49(1):30−40. doi: 10.28920/dhm49.1.30-40. PMID: 30856665. PMCID: PMC6526048.
Immersion pulmonary oedema: a cardiological perspective
Peter T Wilmshurst
Royal Stoke University Hospital, Stoke-on-Trent, ST4 6QG, United Kingdom
Key words
Cold; Exercise; Hypertension; Rebreathers; Renal artery stenosis; Takotsubu cardiomyopathy; Transpulmonary pressure; Case reports
Abstract
(Wilmshurst PT. Immersion pulmonary oedema: a cardiological perspective. Diving and Hyperbaric Medicine. 2019 March 31;49(1):30–40. doi: 10.28920/dhm49.1.30-40. PMID: 30856665. PMCID: PMC6526048.)
It is postulated that immersion pulmonary oedema (IPE) occurs because of combinations of factors that each increase the hydrostatic pressure gradient between the pulmonary capillaries and the alveoli. The factors, by definition, include the effects of immersion, particularly raised central blood volume and hence cardiac filling pressures. Breathing against a negative pressure is important but the magnitude of the effect depends on the relation of the diver’s lung centroid to the source of the breathing gas and the breathing characteristics of diving equipment. Other factors are cold-induced vasoconstriction, exertion and emotional stress, but variations of the responses of individuals to these stimuli are important. Hypertension is the most frequent cardiovascular disease predisposing to IPE but other medical conditions are implicated in some patients.
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.
2019 March;49(1)
Diving Hyperb Med. 2019 March;49(1):41−47. doi: 10.28920/dhm49.1.41-47. PMID: 30856666. PMCID: PMC6526049.
Diving and attention deficit hyperactivity disorder
Abraham L Querido1, Robert A van Hulst2
1 Praktijk Querido, Larenseweg 14, Hilversum, The Netherlands
2 Department of Experimental Intensive Care and Anaesthesiology/Hyperbaric Medicine, Academic Medical Center, Amsterdam
Corresponding author: Abraham L Querido, Praktijk Querido, Larenseweg 14, Hilversum, The Netherlands
Key words
ADHD; Medications; Fitness to dive; Diving medicine; Recreational diving; Side effects; Review article
Abstract
(Querido AL, van Hulst RA. Diving and attention deficit hyperactivity disorder. Diving and Hyperbaric Medicine. 2019 March 31;49(1):41–47. doi: 10.28920/dhm49.1.41-47. PMID: 30856666. PMCID: PMC6526049.)
Attention deficit hyperactivity disorder (ADHD) is a psychiatric condition that affects attention, concentration, impulse control and awareness. Not only these symptoms, but also the medications used to treat ADHD (psychostimulants) pose a risk to both the diver and his or her buddy. This article presents guidelines for recreational diving in combination with ADHD and psychostimulants. These guidelines are based solely on ‘expert’ opinion and were adopted at a meeting of the Dutch Association for Diving Medicine in 2017.
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.
2019 March;49(1)
Diving Hyperb Med. 2019 March;49(1):48−56. doi: 10.28920/dhm49.1.48-56. PMID: 30856667. PMCID: PMC6526050.
The performance of ‘temperature stick’ carbon dioxide absorbent monitors in diving rebreathers
Mårten Silvanius1,4, Simon J Mitchell2, Neal W Pollock3, Oskar Frånberg4, Mikael Gennser5, Jerry Lindén1, Peter Mesley6, Nicholas Gant7
1 Swedish Armed Forces Diving and Naval Medicine Centre, Karlskrona, Sweden
2 Department of Anaesthesiology, University of Auckland, Auckland, New Zealand
3 Department of Kinesiology, Université Laval Québec, QC, Canada
4 Blekinge Institute of Technology, Karlskrona, Sweden
5 School of Technology and Health, KTH Royal Institute of Technology, Stockholm, Sweden
6 Lust for Rust Diving Expeditions, Auckland
7 Department of Exercise Sciences, University of Auckland
Corresponding author: Nicholas Gant, Department of Exercise Sciences, Centre for Brain Research, University of Auckland, Auckland 1142, New Zealand
Key words
Hypercapnia; Monitoring; Technical diving; Soda lime; Equipment
Abstract
(Silvanius M, Mitchell SJ, Pollock NW, Frånberg O, Gennser M, Lindén J, Mesley P, Gant N. The performance of ‘temperature stick’ carbon dioxide absorbent monitors in diving rebreathers. Diving and Hyperbaric Medicine. 2019 March 31;49(1):48–56. doi: 10.28920/dhm49.1.48-56. PMID: 30856667. PMCID: PMC6526050.)
Introduction: Diving rebreathers use canisters containing soda lime to remove carbon dioxide (CO2) from expired gas. Soda lime has a finite ability to absorb CO2. Temperature sticks monitor the exothermic reaction between CO2 and soda lime to predict remaining absorptive capacity. We investigated the accuracy of these predictions in two rebreathers that utilise temperature sticks.
Methods: Inspiration and rEvo rebreathers filled with new soda lime were immersed in water at 19°C and operated on mechanical circuits whose ventilation and CO2-addition parameters simulated dives involving either moderate exercise
(6 MET) throughout (mod-ex), or 90 minutes of 6 MET exercise followed by 2 MET exercise (low-ex) until breakthrough (inspired PCO2 [PiCO2] = 1 kPa). Simulated dives were conducted at surface pressure (sea-level) (low-ex: Inspiration,
n = 5; rEvo, n = 5; mod-ex: Inspiration, n = 7, rEvo, n = 5) and at 3–6 metres’ sea water (msw) depth (mod-ex protocol only: Inspiration, n = 8; rEvo, n = 5).
Results: Operated at surface pressure, both rebreathers warned appropriately in 4 of 5 low-ex tests but failed to do so in the 12 mod-ex tests. At 3−6 msw depth, warnings preceded breakthrough in 11 of 13 mod-ex tests. The rEvo warned conservatively in all five tests (approximately 60 minutes prior). Inspiration warnings immediately preceded breakthrough in six of eight tests, but were marginally late in one test and 13 minutes late in another.
Conclusion: When operated at even shallow depth, temperature sticks provided timely warning of significant CO2 breakthrough in the scenarios examined. They are much less accurate during simulated exercise at surface pressure.
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: Technical report
Full article available here.
2019 March;49(1)
Diving Hyperb Med. 2019 March;49(1):57−60. doi: 10.28920/dhm49.1.57-60. PMID: 30856668. PMCID: PMC6526052.
Lion’s mane jellyfish (Cyanea capillata) envenoming presenting as suspected decompression sickness
Andrew Trevett1,2, Carolyn Sheehan1,2, Antony Wilkinson1,2, Inez Moss1,2
1 Orkney Hyperbaric Unit, Stromness, Orkney, Scotland
2 Stromness Surgery, John Street, Stromness, Orkney
Corresponding author: Andrew Trevett, Stromness Surgery, John Street, Stromness, Orkney, Scotland, KW16 3AD
Key words
Marine animals; Envenomation; Clinical toxicology; Diving incidents; Case reports
Abstract
(Trevett A, Sheehan C, Wilkinson A, Moss I. Lion’s mane jellyfish (Cyanea capillata) envenoming presenting as suspected decompression sickness. Diving and Hyperbaric Medicine. 2019 March 31;49(1):57–60. doi: 10.28920/dhm49.1.57-60. PMID: 30856668. PMCID: PMC6526052.)
Lion’s mane jellyfish stings are usually characterised by local inflammation, especially weals. Systemic symptoms are not widely described although there is a well known fictional description of a fatal reaction to envenoming. We describe five divers presenting with suspected decompression sickness, where the probable diagnosis was jellyfish envenoming.
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.
2019 March;49(1)
Diving Hyperb Med. 2019 March;49(1):61−63. doi: 10.28920/dhm49.1.61-63. PMID: 30856669. PMCID: PMC6526053.
Massive portal venous gas embolism after scuba diving
Romain Siaffa1, Marc Luciani2, Bruno Grandjean2, Mathieu Coulange3,4
1 Navy Medical Department, Naval base of Toulon, Toulon, France
2 Department of Hyperbaric Medicine, Notre-Dame de la Miséricorde Hospital, Ajaccio, France
3 Department of Hyperbaric Medicine, Sainte-Marguerite Hospital, APHM, Marseille, France
4 UMR MD2, Aix Marseille University and Institute of Biological Research of the Army, Marseille
Corresponding author: Romain Siaffa, Sainte-Anne Military Hospital, 2 Boulevard Sainte Anne, 83000 Toulon, France
Key words
Decompression sickness; Liver; Gastrointestinal tract; Hyperbaric oxygen therapy
Abstract
(Siaffa R, Luciani M, Grandjean B, Coulange M. Massive portal venous gas embolism after scuba diving. Diving and Hyperbaric Medicine. 2019 March 31;49(1):61–63. doi: 10.28920/dhm49.1.61-63. PMID: 30856669. PMCID: PMC6526053.)
Introduction: Portal venous gas from a diving injury is an infrequent finding and only a few cases are described. We report a case of severe decompression sickness (DCS) associated with a massive amount of gas in the portal and mesenteric veins.
Case report: A 49-year-old man suffered from DCS after two deep dives on the same day. He presented with cutaneous, neurological and pulmonary symptoms associated with hypoxaemia. He had no abdominal pain. A computed tomography (CT) scan showed large quantities of hepatic and portal venous gas and excluded other explanations for its presence. All symptoms disappeared with hyperbaric oxygen therapy and there were no further complications.
Discussion and conclusion: The role of portal venous gas in DCS is not obvious. Isolated portal venous gas seems to cause no obvious harm. Medical imaging should be considered for differential diagnosis and to prevent some complications, especially in divers presenting with abdominal pain.
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.
2019 March;49(1)
Diving Hyperb Med. 2019 March;49(1):64. doi: 10.28920/dhm49.1.64. PMID: 30856670. PMCID: PMC6526047.
Gas micronuclei that underlie decompression bubbles and decompression sickness have not been identified
David J Doolette
Corresponding author: David J Doolette, Associate Professor, Department of Anaesthesiology, The University of Auckland, Auckland, New Zealand
Key words
Letters (to the Editor); All other relevant keywords are in the title
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