Diving and Hyperbaric Medicine The Journal of the South Pacific Underwater Medicine Society and the European Underwater and Baromedical Society Volume 44 No. 4 December 2014 Inner ear barotrauma Controversies in hyperbaric medicine – Réunion2013 Submarine escape – the CO2-off effect and Valsalvas Variations in no-stop times among dive computers Holter 12-lead ECG monitoring of scuba divers Print Post Approved PP 100007612 ISSN 1833-3516, ABN 29 299 823 713 Diving and Hyperbaric Medicine Volume 44 No. 4 December 2014 PURPOSES OF THE SOCIETIES To promote and facilitate the study of all aspects of underwater and hyperbaric medicine To provide information on underwater and hyperbaric medicine To publish a journal and to convene members of each Society annually at a scientific conference SOUTH PACIFIC UNDERWATER EUROPEAN UNDERWATER AND MEDICINE SOCIETY BAROMEDICAL SOCIETY OFFICE HOLDERS OFFICE HOLDERS President President David Smart <[email protected]> Costantino Balestra <[email protected]> Past President Vice President Mike Bennett <[email protected]> Jacek Kot <[email protected]> Secretary Immediate Past President Karen Richardson <[email protected]> Peter Germonpré <[email protected]> Treasurer Past President Peter Smith <[email protected]> Alf Brubakk <[email protected]> Education Officer Honorary Secretary David Wilkinson <[email protected]> Peter Germonpré <[email protected]> Chairman ANZHMG Member-at-Large 2014 John Orton <[email protected]> Robert van Hulst <[email protected]> Committee Members Member-at-Large 2013 Denise Blake <[email protected]> Pierre Lafère <[email protected]> Simon Mitchell <[email protected]> Member-at-Large 2012 Janine Gregson <[email protected]> Lesley Blogg <[email protected]> Webmaster Liaison Officer Joel Hissink <[email protected]> Phil Bryson <[email protected]> ADMINISTRATION ADMINISTRATION Membership Honorary Treasurer & Membership Secretary Steve Goble <[email protected]> Patricia Wooding <[email protected]> 16 Burselm Avenue, Hainault, Ilford MEMBERSHIP Essex, IG6 3EH, United Kingdom For further information on SPUMS and to complete a membership Phone & Fax: +44-(0)20-85001778 application, go to the Society’s website: <www.spums.org.au> The official address for SPUMS is: MEMBERSHIP c/o Australian and New Zealand College of Anaesthetists, For further information on EUBS and to complete a membership 630 St Kilda Road, Melbourne, Victoria 3004, Australia application, go to the Society’s website: <www.eubs.org> SPUMS is incoprorated in Victoria A0020660B DIVING and HYPERBARIC MEDICINE <www.dhmjournal.com> Editor: Editorial Board: Michael Davis <[email protected]> Costantino Balestra, Belgium c/- Hyperbaric Medicine Unit Michael Bennett, Australia Christchurch Hospital, Private Bag 4710 Alf Brubakk, Norway Christchurch, New Zealand David Doolette, USA Phone: +64-(0)3-364-0045 or (0)3-329-6857 Peter Germonpré, Belgium Fax: +64-(0)3-364-0817 or (0)3-329-6810 Jane Heyworth, Australia European (Deputy) Editor: Jacek Kot, Poland Lesley Blogg <[email protected]> Simon Mitchell, New Zealand Editorial Assistant: Claus-Martin Muth, Germany Nicky McNeish <[email protected]> Neal Pollock, USA Journal distribution: Monica Rocco, Italy Steve Goble <[email protected]> Martin Sayer, United Kingdom Journal submissions: Erika Schagatay, Sweden Submissions should be sent to <[email protected]> David Smart, Australia Robert van Hulst, The Netherlands Diving and Hyperbaric Medicine is published jointly by the South Pacific Underwater Medicine Society and the European Underwater and Baromedical Society (ISSN 1833-3516, ABN 29 299 823 713) Diving and Hyperbaric Medicine Volume 44 No. 4 December 2014 185 Editorials Hydrophobicity: the link between bubbles, bubblers and autoimmunity? Costantino Balestra, President EUBS Some data show that divers can be divided into two groups: autoimmune diseases and to decompression stress (bubblers ‘bubblers’ and ‘non-bubblers’; no hypothesis has proposed vs. non-bubblers). The presence of hydrophobic spots and a generally accepted explanation for such a phenomenon. the availability of certain proteins may determine the timing of onset of the autoimmune disease. This might explain the Hills demonstrated on electron microscopy an oligolamellar early appearance of Type I diabetes and the later onset of lipid lining on the luminal aspect of ovine blood vessels.1 other diseases. He also provided evidence of hydrophobicity, using the measured angle to a small (5μl) drop of water. The This explanation of the bubblers and non-bubblers division hydrophobicity was reduced by rinsing these vessels with is consistent with the ‘de-nucleation’ processes as applied to chloroform, which led to this lining being identified as humans before diving and explains why mechanical energy phospholipids. Hills suggested that the deposition of lung such as vibration, oxygen breathing (at a time interval before surfactants created this hydrophobic lining. Arieli and diving that is incompatible with desaturation), thermal Marmur demonstrated clearly defined areas on the surface ‘energy’ and possibly exercise before diving all appear to of blood vessels that fit the suggestion of hydrophobic spots be protective for bubble production.6–9 Once again, science at which bubbles nucleate and grow after decompression and research in diving show increasingly wider applications from higher pressure.2 Tiny, flat gas nanobubbles measuring and connections with other physiological and pathological 5–100 nm form spontaneously when a smooth hydrophobic processes. surface is submerged in water containing dissolved gas.3 One might suggest, therefore, that a permanent layer of References nanobubbles covers these hydrophobic intra-vascular spots. 1 Hills BA. A hydrophobic oligolamellar lining to the vascular Protein interactions lumen in some organs. Undersea Biomedical Research. 1992;19:107-20. The chain of amino acids in a protein may include 2 Arieli R, Marmur A. Ex vivo bubble production from ovine large blood vessels: Size on detachment and evidence of hydrophobic acids, and the -helices are also the most α “active spots”. Resp Physiol Neurobiol. 2014;200:110-7. common structural elements of the protein to cross biological 3 Arieli R, Marmur A. Dynamics of gas micronuclei formed on membranes. Because hydrophobicity is high for a gaseous a flat hydrophobic surface, the predecessors of decompression phase, the hydrophobic regions in proteins will react with the bubbles. Resp Physiol Neurobiol. 2013;185:647-52. gaseous phase. In contact with a gas phase, the configuration 4 Philp RB, Inwood MJ, Warren BA. Interactions between of a protein will be altered and the denatured protein will gas bubbles and components of the blood: implications in change its immunochemical properties. This process occurs decompression sickness. Aerospace Med. 1972;43:946-53. with bubbles in the blood.4 5 Vadasz Z, Haj T, Kessel A, Toubi E. Age-related autoimmunity. BMC medicine. 2013;11:94. 6 Germonpre P, Pontier JM, Gempp E, Blatteau JE, Deneweth S, Surfactants act against proteins and cause autoimmune Lafere P, et al. Pre-dive vibration effect on bubble formation diseases after a 30-m dive requiring a decompression stop. Aviat Space Environ Med. 2009;80:1044-8. Large protein molecules are probably carried in different 7 Castagna O, Gempp E, Blatteau JE. Pre-dive normobaric quantities and with different timing in the blood. When a oxygen reduces bubble formation in scuba divers. Eur J Appl large molecule containing a hydrophobic domain encounters Physiol. 2009;106:167-72. the strong hydrophobicity of the nanobubble layer at a 8 Blatteau JE, Gempp E, Balestra C, Mets T, Germonpre P. surfactant spot, it will adhere to the spot and its altered Predive sauna and venous gas bubbles upon decompression configuration will be recognized as a foreign molecule, from 400 kPa. Aviat Space Environ Med. 2008;79:1100-5. 9 Madden D, Thom SR, Yang M, Bhopale VM, Ljubkovic M, setting in motion an autoimmune response. Autoimmunity Dujic Z. High intensity cycling before SCUBA diving reduces 5 increases with age, which is itself considered a risk factor post-decompression microparticle production and neutrophil for decompression sickness (DCS) in human divers. If the activation. Eur J Appl Physiol. 2014;114:1955-61. hydrophobically active spots increase in area and number with age, when added surfactants are deposited, this may E-mail: <[email protected]> explain the concomitant increase in the risk of DCS and in autoimmune diseases. Key words Bubbles, decompression sickness, endothelium, surfactant, A large variability in the prevalence of hydrophobic editorial spots in humans may explain differences in sensitivity to 186 Diving and Hyperbaric Medicine Volume 44 No. 4 December 2014 David Smart, President SPUMS of journal processes so that communication is enhanced. Since my last report, the SPUMS Executive has completed At the time of writing there was still some uncertainty a rewrite of the Purposes and Rules to comply with the new regarding the ANZCA Certificate in Diving and Hyperbaric Consumer Affairs Victoria Model Rules Structure. At a Medicine. Commenced over a decade ago, this qualification Special General Meeting on 01 November in Sydney, these is regarded as the highest level achievable in the field of were adopted unanimously. The completion of this tedious diving and hyperbaric medicine in Australia