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Coastguard Release Diving Statistics With Video Podcast

Numbers of diving related incidents remained at low levels last year, according to Coastguard statistics released today.

During 2008, the UK Coastguard dealt with 166 diving-related incidents, including cases of decompression illness, medical emergencies and broken down vessels. Eight fatalities were recorded. The greatest single type of incident is still decompression illness (DCI) which accounts for 65 incidents. A further 33 incidents are attributed to rapid ascent, which may have developed into DCI.

“Make sure that you are well qualified and experienced before diving,” Ken Bazeley, National Diving Liaison Officer for Her Majesty’s Coastguard, has advised. “Keep a close eye on the weather and sea conditions and make personal fitness a top priority for safe diving. Familiarize yourself with new or different gear before diving and ensure that you dive within your limits.

If you would like to remind yourself about key safety points visit our website (www.mcapodcasts.co.uk) and watch our diving video podcast.”

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Undersea Hyperb Med. 2008 Nov-Dec;35(6):393-406.Links

Common causes of open-circuit recreational diving fatalities.

Denoble PJ, Caruso JL, Dear Gde L, Pieper CF, Vann RD.

Divers Alert Network, Duke University Medical Center, Durham, NC 27710, USA.

Diving fatalities causes were investigated in 947 recreational open-circuit scuba diving deaths from 1992-2003. Where possible, cases were classified at each step of a four step sequence: trigger, disabling agent, disabling injury, cause of death (COD).

The most frequent adverse events within each step were: (a) triggers 41% insufficient gas, 20% entrapment, 15% equipment problems; (b) disabling agents–55% emergency ascent, 27% insufficient gas, 13% buoyancy trouble; (c) disabling injuries–33% asphyxia, 29% arterial gas embolism (AGE), 26% cardiac incidents; and (d) COD–70% drowning, 14% AGE, 13% cardiac incidents. We concluded that disabling injuries were more relevant than COD as drowning was often secondary to a disabling injury.

Frequencies and/ or associations with risk factors were investigated for each disabling injury by logistic regression. (The reference group for each injury was all other injuries.)

Frequencies and/or associations included: (a) asphyxia–40% entrapment (Odds Ratio, OR > or = 30), 32% insufficient gas (OR = 15.9), 17% buoyancy trouble, 15% equipment trouble (OR = 4.5), 11% rough water, drysuit (OR = 4.1), female gender (OR = 2.1); (b) AGE–96% emergency ascent (OR > or = 30), 63% insufficient gas, 17% equipment trouble, 9% entrapment; (c) cardiac incidents–cardiovascular disease (OR = 10.5), age > 40 (OR = 5.9).

Minimizing the frequent adverse events would have the greatest impact on reducing diving deaths.

PMID: 19175195 [PubMed - indexed for MEDLINE]

Related Articles

• Scuba diving deaths: a review and approach for the pathologist. [Leg Med Annu. 1977]
• ReviewRecreational scuba diving, patent foramen ovale and their associated risks. [Swiss Med Wkly. 2001]
• ReviewDiving and marine medicine review part II: diving diseases. [J Travel Med. 1999]
• Investigation of scuba deaths. [J Sports Med. 1974]
• Skin diving fatalities in New Zealand. [N Z Med J. 1979]

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Aviat Space Environ Med. 2009 Jan;80(1):2-4.Links

Cerebral white-matter lesions in asymptomatic military divers.

Erdem I, Yildiz S, Uzun G, Sonmez G, Senol MG, Mutluoglu M, Mutlu H, Oner B.

Department of Radiology, Taksim Teaching and Research Hospital, Taksim, Istanbul, Turkey.

INTRODUCTION: There is some concern that over a period of years, diving may produce cumulative neurological injury even in divers who have no history of decompression sickness. We evaluated asymptomatic divers and controls for cerebral white-matter lesions using magnetic resonance imaging (MRI).

METHODS: The study enrolled 113 male military divers (34.4 +/- 5.6 yr) and 65 non-diving men (33.1 +/- 9.0 yr) in good health. Exclusion criteria included any condition that might be expected to produce neurological effects. Patent foramen ovale was not assessed. A questionnaire was used to elicit diving history. A 1.5-T MRI device was used to acquire T1, T2-weighted, and fluid attenuated inversion recovery (FLAIR) images of the brain. A lesion was counted if it appeared hyperintense on both T2-weighted and FLAIR images. RESULTS: MRI revealed brain lesions in 26 of 113 divers (23%) and in 7 of 65 (11%) controls, a difference that was statistically significant. There was no significant difference between the groups with respect to blood pressure, smoking history, or alcohol consumption, and no subject reported a history of head trauma or migraine. There was no relationship between MRI findings and age, diving history, or lipid profile in divers.

DISCUSSION: The higher incidence of lesions in the cerebral white matter of divers confirms the possibility that cumulative, subclinical injury to the neurological system may affect the long-term health of military and recreational divers.

PMID: 19180851 [PubMed - indexed for MEDLINE]

Related Articles

• Does diving damage the brain? MR control study of divers’ central nervous system. [Acta Radiol. 2000]
• Incidence of ischemic brain lesions in hyperbaric chamber inside attendants. [Adv Ther. 2006]
• Dysbaric osteonecrosis screening in Turkish Navy divers. [Aviat Space Environ Med. 2008]
• ReviewRecreational scuba diving, patent foramen ovale and their associated risks. [Swiss Med Wkly. 2001]
• ReviewDysbaric disorders: aseptic bone necrosis in tunnel workers and divers. [Baillieres Clin Rheumatol. 1989]

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J Appl Physiol. 2009 Jan;106(1):298-301.

Selective vulnerability of the inner ear to decompression sickness in divers with right-to-left shunt: the role of tissue gas supersaturation.

Mitchell SJ, Doolette DJ.

Dept. of Anesthesiology, University of Auckland, Auckland, New Zealand. dr.m@xtra.co.nz

Inner ear decompression sickness has been strongly associated with the presence of right-to-left shunts. The implied involvement of intravascular bubbles shunted from venous to arterial circulations is inconsistent with the frequent absence of cerebral symptoms in these cases. If arterial bubbles reach the labyrinthine artery, they must also be distributing widely in the brain. This discrepancy could be explained by slower inert gas washout from the inner ear after diving and the consequent tendency for arterial bubbles entering this supersaturated territory to grow because of inward diffusion of gas. Published models for inner ear and brain inert gas kinetics were used to predict tissue gas tensions after an air dive to 4 atm absolute for 25 min. The models predict half-times for nitrogen washout of 8.8 min and 1.2 min for the inner ear and brain, respectively. The inner ear remains supersaturated with nitrogen for longer after diving than the brain, and in the simulated dive, for a period that corresponds with the latency of typical cases. It is therefore plausible that prolonged inner ear inert gas supersaturation contributes to the selective vulnerability of the inner ear to short latency decompression sickness in divers with right-to-left shunt.

PMID: 18801958 [PubMed - indexed for MEDLINE]

Related Articles

• Review Recreational scuba diving, patent foramen ovale and their associated risks. [Swiss Med Wkly. 2001]
• Biophysical basis for inner ear decompression sickness. [J Appl Physiol. 2003]
• Embolic inner ear decompression illness: correlation with a right-to-left shunt. [Laryngoscope. 2003]
• Association between right-to-left shunts and brain lesions in sport divers. [Aviat Space Environ Med. 2003]
• Review The physiological kinetics of nitrogen and the prevention of decompression sickness. [Clin Pharmacokinet. 2001]

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Undercurrent — Consumer Reporting for
the Scuba Diving Community since 1975
www.undercurrent.org

Dive News

March 10, 2009

Rebreather Dive Hose Recall: Silent Diving Systems (SDS) has recalled approximately 820 scuba diving hoses that may have been made without crimps, posing a potential drowning hazard. They can allow gas to leak or water to into the re-breather unit. The hoses were sold for Inspiration, Evolution and Evolution Plus rebreathers between January 2007 through August 2008. SDS president Mike Fowler tells Undercurrent that because the company carried a list of each buyer, it was able to contact each person within three days. If you do own one of these SDS models, check the dive hose. If it’s uncrimped, call SDS at 603-447-2600 or e-mail service@silentdiving.com. Fowler, by the way, recently played an underwater bad guy on CSI Miami, filling in for a stuntman who was too short for the director’s taste.

The Best of PNG Diving on The Star Dancer, Plus A $500 Airfare Credit: We like to keep you apprised of deals from dive operators our readers approve of, and here’s a good one. Peter Hughes e-mailed to say that he’s so pleased about the refurbishing of the Star Dancer that he’s personally directing in Papua New Guinea, he’ll rebate $500 of your airfare if you sign up for a trip — that applies even if you book the flight yourself or use frequent-flyer miles. “Tell Undercurrent subscribers and their friends to come diving on our beautifully updated and completely renovated Star Dancer for the best diving in the Coral Triangle. Amazing reefs and marine life at the Witu Islands and Father’s Reef, and luxury they won’t believe.” Anyone who signs up for a cruise and mentions Undercurrent will get a free safety sausage along with the $500 refund/credit. Call 1-800-9-DANCER or 305-669-9391. You must book before May 15, 2009 for travel done by Dec. 31, 2009. See Peter Hughes’ website (www.peterhughes.com )for more details.

Google Earth Now Has Amazing Ocean Satellite Data: Free Google Earth software now lets you explore ocean-floor topography. Famed oceanographer Sylvia Earle met Google Earth manager John Henke in 2006 and joked that the software should be called “Google Dirt” because it ignored the parts of the planet covered by water. Since then, the pair worked to add ocean data, like descriptions of aquatic ecosystems, changing ocean surface temperatures and migration patterns of the great white shark. Download Google Earth 5.0 for free at http://earth.google.com and get closeups of everything from the Florida Keys to Raja Ampat

What Happened To Innovations In The Dive Industry?: Bret Gilliam, who has had jobs of more impact than any five people in the dive industry, takes no prisoners as he challenges industry leaders in the current issue of Undercurrent. “I lament the days when manufacturing companies were run by real divers. What happened to the spirit of innovation? Where are the new products that should be emerging from this exciting technological period?” Read Bret’s outspoken opinion — and his pointed suggestions for improvement — online at Undercurrent. On the home page, go to “The March Issue” and click on “A Personal Perspective on Dive Innovation.”

Shark Shields In Australia: Police in New South Wales may make these shark-deterring devices mandatory for its divers after a spate of shark attacks in the territory (five so far this year, compared to eight for all of 2008). One of the most recent victims was Navy diver Paul de Gelder, who lost an arm and a leg after being attacked on February 11 by presumably a bull shark during a training exercise in Sydney Harbour. The makers of Shark Shield (http://www.sharkshield.com/Content/Home) say they have seen a massive rise in demand for the device, a small black box with an antenna emitting strong electrical impulses supposedly painful to sharks, with a 200 percent increase in inquiries from Australian dive and surf shops over the past two months.

Step Zero: Getting Started on a Scuba Photo Trip: Seven days on an underwater photography trip to a resort or on a liveaboard requires twice as many days to plan and organize, so if you haven’t done it completely and correctly you can waste a bundle of time and money and shed buckets of tears over missed shots. Not only does this 80 page book by Dennis Adams and Cathy and Peter Swan provide a full 17 page checklist of everything you will need to travel and shoot, but it provides an orderly planning and procurement schedule and scores of insider’s tips. Its an essential book for anyone planning a first time photo safari, but just as useful for any of us who have spent a week kicking ourselves about leaving home that one crucial item and having to beg, borrow and jury rig while out of the water missing that once-in-a-lifetime opportunity below. You can buy it at Undercurrent at a low price offered by Amazon.com, and our profits for the sale — in fact, our profit from any purchase you make while there — will go directly to projects helping to save coral reefs. (88 pages)

Cannons Stolen From St. Kitts Dive Site: White House Bay is no longer such a memorable wreck site because its main attraction, five historical cannons, was apparently stolen overnight. The cannons were from a sunken 18th-century English troop ship lying in 10 feet of water, and were left behind when other artifacts were removed for preservation. Divers reported seeing them until late December, when they suddenly were no longer there. St. Kitts has other wreck sites, but White House Bay is the only one to have been surveyed and studied so far.

Photo Experts Recommend “Shooting Magic” DVD: The pros at Wetpixel.com recommend this 90-minute DVD for underwater photographers wanting to perfect their technique using filters. It follows photographer Alex Mustard during six dives in the Red Sea, three shooting with his digital single-lens reflex camera and three with his compact camera. Mustard demonstrates and describes the techniques needed to produce excellent light photographs, using special filters he co-designed. The DVD is for sale on his Magic Filters website (http://www.magic-filters.com/dvd.html) for $23, plus $4 shipping.

New ‘Psychedelic’ Frogfish Discovered: If you want to see the latest fish confirmed as a new species, go diving with Toby of Maluku Divers, the land-based dive shop in Ambon, Indonesia. He was the guy who discovered the Histiophryne psychedelica, a frogfish that hops rather than swims. Not seeing the fish in its ID books, Maluku Divers turned to Ted Pietsch, a fishery sciences expert at the University of Washington. Pietsch and team confirmed the new species and gave it the psychedelic name because of “the cockamamie way these fish swim, some with so little control they look intoxicated and should be cited for DUI”. Watch a video of this frogfish’s swimming style here: http://www.eurekalert.org/multimedia/pub/12517.php

Divers Find Intact Hotel 300 Feet Deep in Lake: The Attakulla Lodge stands at the bottom of Lake Jocassee, a manmade lake in upstate South Carolina. It was the last building standing in a neighborhood washed away in 1973 by a dam that flooded Jocassee Valley. The lodge’s owner fought the dam development and was able to keep his building from being demolished, but not from having it eventually flooded. CNN did a story on a woman who grew up in Attakulla Lodge and the technical divers who found her childhood home underwater. Watch the video here: http://www.cnn.com/video/#/video/bestoftv/2009/02/23/ntm.lake.jocassee.cnn

Read The Current Issue Online: Did you know that any subscriber/member of Undercurrent can read the current issue online? You can use this link (http://www.undercurrent.org/members/UCnow/currentissue.pdf) about the first of each month to download the issue using your registered username and password (go to http://www.undercurrent.org/subscribers/UCnow/SubOMSignup.php if you’re a subscriber and haven’t yet registered). Not the November/December issue, however - that’s the Chapbook, which is available in the Travel section pages.

Coming Up In Undercurrent: Riding Rock Inn in San Salvador, Bahamas: worth the puddle-jumper ride from Miami? . . .Wananavu Beach Resort, Fiji: an updated report on this divers’ favorite . . .part two of ‘Why Divers Die’: overweighting and uninflated BCDs . . . pros and cons of organizing a group dive trip . . . the anatomy of free flow . . .does argon help with drysuit warmth? . . .Mike Ball explains his new device to recover lost divers . . . should you sauna before a dive? . . .how you can dive for free and for a good purpose . . . and much more

Ben Davison, editor/publisher
Contact Ben

Note: Our travel writers never announce their purpose, are unknown to the destination, and receive no complimentary services or compensation from the dive operators or resort. Dive trips listed in our emails must be offered by a well-regarded operation that has been reviewed positively by our readers. The operator must include a special offer for Undercurrent subscribers and supporters. Undercurrent is a 501 (c)(3) not-for-profit organization and in some cases the operator has made a donation.

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FOR IMMEDIATE DISTRIBUTION

09 March 2009

Main Title:  DAN Gets the Hat Trick with a THIRD New Member Benefit

Subtitle:  DAN offers online training seminars free to members

DURHAM, NC –  First came the Worldcue^®Planner Travel Intelligence^® Resource.  Then came AlertDiver.com.  Now, Divers Alert Network^® (DAN^®) brings its Members a third new membership benefit with free online training seminars.

The DAN Online Training Seminars are informative, web-based seminars that allow divers to learn about diving and dive medicine from the comfort of home.  Current topics include ears and diving, diabetes and diving, and decompression illness.  Additional seminars will be made available throughout the year.

“DAN knows the value of information and how it can increase a diver’s safety,” says Dan Orr, DAN President and CEO. “So to be able to bring our Members a third new benefit that provides information, especially at the high-quality level of a DAN program, is really exciting.”

All online seminars are free to DAN Members, and access is automatically included with DAN Membership.  Non-members are welcome to take the seminars at a cost of $25 per seminar.

“What’s great is that any diver can benefit from these seminars, from the newest diver to the pro,” says Orr. “So to be able to provide them as an automatic part of DAN Membership just reinforces the organization’s dedication to increasing diver safety. These first few seminars are just the start, and we’re really looking forward to expanding this program.”

To access the seminars, simply visit the link and log in as a DAN Member (or follow the instructions if you’re not and need to provide payment).

It’s a great time to be a DAN Member.  The Online Training Seminars create the hat trick of new benefits, but it’s the DAN Members who really score.

For additional information, please visit www.DiversAlertNetwork.org or call (800) 446-2671.

Chapter 8 of the serial adventure short story Frog Head Key is now online and ready for download. If you haven’t been following along, there is still time to catch up before the exciting conclusion. Forward this to all your friends so they know about it too!

On the website, you can also check out a special offer on signed copies of Eric’s books.

Chapter 8

Kia tends to the hole in Jackson’s leg from the shotgun blast while Littlebear makes arrangements to go back after Snake and his men.

Download the PDFs from Eric Douglas’s website www.booksbyeric.com, download the audio files, or subscribe to the podcast on iTunes and have the files downloaded automatically directly to your computer. http://itunes.apple.com/WebObjects/MZStore.woa/wa/viewPodcast?id=305343610

Eric Douglas
Author of Cayman Cowboys, Flooding Hollywood, Scuba Diving Safety and now Guardian’s Keep
www.booksbyeric.com

Aviat Space Environ Med. 2009 Jan;80(1):15-9.

Bubble formation and endothelial function before and after 3 months of dive training.

Pontier JM, Guerrero F, Castagna O.

Medicine Department, French Navy Diving School, Toulon Army, France. jm.pontier@free.fr

INTRODUCTION: It has been suggested that repeated compression-decompression cycles reduce diver susceptibility to decompression sickness (DCS). This study examined whether intensive scuba dive training would reduce bubble formation and modulate endothelial function as shown by skin circulation.

METHODS: There were 22 military divers who were studied before and after a 90-d program of physical training and open-sea air diving (mean 67 dives total). Skin blood flow in the forearm was measured at rest (baseline), during post-occlusive hyperemia (endothelium-dependent vasodilatation), and with local heating to 42 degrees C (maximal vasodilatation). Subjects were also examined by pulsed Doppler for venous bubbles 30, 60, and 90 min after surfacing from a hyperbaric exposure to 400 kPa (30 msw) for 30 min in a dry chamber.

RESULTS: None of the divers experienced DCS during the training period. There was no change in weight, body mass index, maximal oxygen uptake, or endothelial function. Bubble grades by the Kisman Integrated Severity Score were significantly decreased immediately after the diving training period (3.6 +/- 9.2 vs. 16.4 +/- 14.3) and increased 3 mo after this period (10.3 +/- 13.9 vs. 3.6 +/- 9.2).

DISCUSSION: The results highlight that repeated scuba dives and regular physical exercise activity reduce bubble formation and probably have a protective effect against DCS risk. Although this phenomenon has been observed for decades, the mechanism remains complex and the results cannot elucidate the effects of physical exercise and NO production. Bubble formation could activate the stress response which could be the basis for diving acclimatization.

PMID: 19180853 [PubMed - indexed for MEDLINE]

Related Articles

• Aerobic exercise 2 hours before a dive to 30 msw decreases bubble formation after decompression. [Aviat Space Environ Med. 2005]
• Exogenous nitric oxide and bubble formation in divers. [Med Sci Sports Exerc. 2006]
• Venous bubble count declines during strenuous exercise after an open sea dive to 30 m. [Aviat Space Environ Med. 2006]
• ReviewRecreational scuba diving, patent foramen ovale and their associated risks. [Swiss Med Wkly. 2001]
• ReviewPatent foramen ovale and diving. [Cardiol Clin. 2005]