Diving and Hyperbaric Medicine The Journal of the South Pacific Underwater Medicine Society (Incorporated in Victoria) A0020660B and the European Underwater and Baromedical Society Volume 40 No. 1 March 2010 Extreme breath-hold diving - Part II Perfluorocarbons – promise in decompression sickness? Nitric oxide as a marker of inflammation in diving Instrumenting the breath-hold diver In-dive rehydration for the working diver ISSN 1833 3516 Print Post Approved ABN 29 299 823 713 PP 331758/0015 Diving and Hyperbaric Medicine Volume 40 No. 1 March 2010 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 Mike Bennett <[email protected]> Peter Germonpré <[email protected]> PastPresident Vice President Chris Acott <[email protected]> Costantino Balestra <[email protected]> Secretary Immediate Past President Sarah Lockley <[email protected]> Alf Brubakk < a l f . b r u b a k k @ e u b s . o r g > Treasurer Past President Jan Lehm <[email protected]> Noemi Bitterman <[email protected]> Education Officer Honorary Secretary David Smart <[email protected]> Joerg Schmutz < j o e rg . s c h m u t z @ e u b s . o rg > Public Officer Member at Large 2009 Vanessa Haller <[email protected]> Andreas Møllerløkken <[email protected]> Chairman ANZHMG Member at Large 2008 David Smart <[email protected]> Dr Peter Knessl < p e t e r. k n e s s l @ e u b s . o r g > Committee Members Member at Large 2007 Glen Hawkins <[email protected]> Phil Bryson < p h i l . b r y s o n @ e u b s . o r g > Scott Squires <[email protected]> Guy Williams < g u y w @ i m a p . c c > ADMINISTRATION ADMINISTRATION Membership Honorary Treasurer & Membership Secretary Steve Goble < a d m i n @ s p u m s . o r g . a u > Patricia Wooding <[email protected]> Editorial Assistant 16 Burselm Avenue, Nicky McNeish < s p u m s j @ c d h b . g o v t . n z > Hainault, Ilford Essex, IG6 3EH MEMBERSHIP United Kingdom For details of the different types of SPUMS membership Phone & Fax: +44-(0)20-85001778 and further information on the Society, or to complete a membership application, go to the Society’s website: MEMBERSHIP <www.spums.org.au> For further information on EUBS and to complete a membership application go to the Society’s website: The official address for SPUMS is: <www.eubs.org> c/o Australian and New Zealand College of Anaesthetists, 630 St Kilda Road, Melbourne, Victoria 3004, Australia DIVING and HYPERBARIC MEDICINE The Journal of the South Pacific Underwater Medicine Society and the European Underwater and Baromedical Society Editor and Publisher: Editorial Board: Michael Davis < e d i t o r @ d h m j o u r n a l . c o m > Mike Bennett, Australia c/- Hyperbaric Medicine Unit Alf Brubakk, Norway Christchurch Hospital, Private Bag 4710 Peter Germonpré, Belgium Christchurch, New Zealand Jacek Kot, Poland Phone: +64(0)33640045 or (0)3-329-6857 Simon Mitchell, New Zealand Fax: +64(0)3364-0817 or (0)3-329-6810 Neal Pollock, USA European Editor: David Smart, Australia Peter Müller <[email protected]> Diving and Hyperbaric Medicine Volume 40 No.1 March 2010 1 competitions. Linked to this work and reported in this The Editor’s offering issue, is the development of miniaturised, computer-based, pressure-resistant technology that will allow physiological Since Peter Germonpré wrote his Presidential message, monitoring of the free-swimming diver. Those of you in the further tragedy has struck from earthquake in Chile, severe Antipodes who follow cricket will have been entertained by floods and storms, and, at the other extreme, drought and the ‘Heart Tracker’ monitoring on TV of individual players famine in many parts of the world. I am aware of a number of during international matches and marvelled at the ability of members of both societies who are involved in helping with young athletes to take their heart rate into the 200s during the human suffering consequent on these natural disasters, play, especially if they are a fast bowler! Such technology, and I am sure that I speak for all in wishing them success of course, has a far more important role in advancing our and safety in their emergency medical work. understanding in both physiological research and clinical medicine, and is likely to become increasingly sophisticated Heparin, steroids, anti-platelet drugs, non-steroidal anti- in the future. inflammatories (NSAIDs) and lignocaine have all been investigated and enthusiastically advocated by some in the In editing this journal, we draw satisfaction from helping search for effective drug-based treatments of decompression authors to clarify their writing. Now that we are receiving illness (DCI). Only NSAIDs, in a single randomised a steadily increasing number of submissions from authors controlled study (RCT) that has not been replicated, have whose first language is not English, this has assumed greater shown any potential benefit as an adjunctive therapy to importance. Even if you are not confident with written hyperbaric oxygen, and then only in terms of reducing English, this office is happy to assist once a paper has been the number of hyperbaric treatments required (by at least provisionally accepted for publication. Often, the reviewers, one, NNT of five patients) to reach a plateau of recovery, as well as critiquing the content of papers, contribute to rather than any improvement in recovery itself. Even fluid this. Language is a dynamic, constantly changing beast, and resuscitation has no convincing evidence to support its use, English is no exception. A recent example for me is having though this is a bit like saying that mechanical ventilation in to abandon (with much heartache!) “apnoea” in favour of the critically ill patient with acute respiratory failure has not the Americanised spelling, “apnea”, which is now used in proved to be life-saving! Other interventions have almost no well over 80% of all publications in this field. clinical outcome evidence of any sort. Adjunctive therapy has been reviewed recently for us by Richard Moon, and in The executive committees of EUBS and SPUMS have a Cochrane review by Michael Bennett et al.1,2 recently reached agreement on their continued cooperation in the publication of this journal. The writer has been appointed The remarkable gas-carrying properties of perfluorocarbons as Editor for a further three years through 2012. I hope to offer new and exciting prospects for acute medicine in serve the societies well and to the best of my abilities, and I several clinical situations. The long history of their research look forward to hearing the views of any of our readers. development and current theoretical and experimental evidence for their use in DCI are provided by Bruce Spiess References in two articles in this issue. What is not mentioned are the very considerable difficulties that present themselves in 1 Moon RE. Adjunctive therapy for decompression illness: developing a meaningful, multi-centre, prospective RCT a review and update. Diving and Hyperbaric Medicine. protocol to assess their role in treating DCI, just as was the 2009;39(2):81-6. case with lignocaine.3 These agents have only been tested 2 Bennett MH, Lehm JP, Mitchell SJ, Wasiak J. Recompression in DCI in animal models and may carry a potential for an and adjunctive therapy for decompression illness (Cochrane Review). In: The Cochrane Library (Issue 2, 2006). increased risk of acute oxygen toxicity with hyperbaric CD005007. oxygen therapy. Nevertheless, we now have the prospect 3 Francis J. A randomised prospective trial of lignocaine in the of a useful adjunctive therapy for the future, particularly in management of acute neurological decompression illness – an severe cases and for first aid treatment in remote sites. update. SPUMS Journal. 2002;32(2):97-105. 4 Schagatay E. Predicting performance in competitive apnea Predicting the future is a risky pastime. In her first review of diving. Part I: static apnea. Diving and Hyperbaric Medicine. extreme breath-hold diving, Professor Schagatay calculated 2009;39(2):88-99. that the likely limit to static apnea duration was probably around 11 minutes plus, but cautioned that not all the Michael Davis potential contributing factors had been accounted for in this estimate.4 Soon after, the static apnea world record was pushed out to 11:35 min, with elite divers predicting that Front page photo of a diver performing a static apnea at the final limit may be in excess of 13 minutes! Her second the 2008 World Championships was taken by Mr Kimmo article probes the physiology of breath-hold swimming Lahtinen of Finland. Kimmo is the current President exercise (without diving to depth), and reviews the safety of AIDA International and has a photographic website procedures in place during these swimming-pool-based <www. freediving.pictures.fi> well worth viewing. 2 Diving and Hyperbaric Medicine Volume 40 No. 1 March 2010 The Presidents’ pages Peter Germonpré group of medical specialists actually has written a scientific President, EUBS paper, but surely 100% could make the effort? You will find that, once you have written one, it is easier to write the Dear friends, second. Just look over the contributions in this and previous issues and convince yourself that you can do this too.