Tuesday, June 9, 2009

Diving With Disabilities



Download pdf
A Real Diving Challenge

This page is written and maintained by
Ernest S Campbell, MD, FACS


Have you ever been on a night dive and had your lights go out? Or, imagine yourself doing a shore dive and you find that someone has tied your feet together; just imagine the difficulty of dragging yourself in and out of the water.

These are just two of the challenges that face disabled people who want to experience the serenity and beauty of scuba diving: the blind person is forever in pitch darkness, the paraplegic faces this wall every day.

In spite of these seemingly insurmountable obstacles, there are many disabled who are participating in scuba diving programs especially designed to assist them to experience our sport safely.

Below are listed various services and contacts for disabled persons who wish to learn more about diving:

Articles

  • Dive Training for the Disabled: What is it Worth? Diver Magazine, August 1997

  • "Soaring Below", by Vicki Stiefel.

  • 'Alert Diver', March/April 1996; a publication of
    DAN (Divers Alert Network)
  • "Diving With Care",

  • Training and Medical Aspects of Diving With Disabilities,
    Kimberly P. Walker, NREMT-P, DAN Training
    Alert Diver, March-April 1996, p. 40.
  • Scuba Diving With Disabilities Robinson, Jill. & A. Dale Fox:

  • (Champagne, Illinois: Leisure Press, a Division of Human
    Kinetics Publishers, Inc. Box 5076 Champagne, Il 61820. 1987)
    "A valuable supplement to any diving manual or class. For the disabled diver or the instructor who wants to teach disabled divers, the book is must reading."


Associations and Clubs and Training


Amazing Seals
amazingseals.com
St. Paul/ Minneapolis Minnesota
Masha Bowen coordinator
(651)263-9707
We have recently started this exiting new program and working with local rehabilitation centers providing scuba experience for disabled divers. We have PADI and HSA certified instructors.



Disabled Diver training in the San Diego area.

John Ellerbrock
PADI Master Instructor
Pinnacle Divers

PinnacleDiver@home.com
619.997.DIVE (3483)


Eels on Wheels Adaptive Scuba Club
Aron Waisman,
12338 Limerick Ave,
Austin, Texas, 78758
(512) 873-9121
awaisman@austin.rr.com
http://www.Eels.org

Article "Challenges of Diving With Disabilities", by Tammie Shelton
http://scuba-doc.com/DivingDisabilities.pdf



National Instructors Association for Divers with Disabilities (NIADD), Dorothy Shrout, P.O. Box 112223, Campbell; CA 95011-2223; (408) 379-6536, (408) 244- 8652 fax
NIADD, San Jose, CA. Contact Frank Degnan at Any Water Sports, (408)244-4433. Frank and Dorothy Shrout organize this.

Handicapped Scuba Association, Jim Gatacre, 1104 El Prado, San Clemente, CA 92672-4637, (714) 498-6128, HSA@HSASCUBA.COM


Houston Disabled Scuba Divers Association, 403 East Nasa Road 1, Suite 325, Webster TX 77598-5314, (713) 477-5556, swa@neosoft.com

Southern Wheelchair Adventurers Association of Galveston-Houston, 403 East Nasa Road 1, Suite 325, Webster TX 77598-5314, (713) 477-5556, (Lytle Seibert); swa@neosoft.com,



Canadian Scuba Diving Clubs for Divers with Disabilities
  • Club Challenge, 3108 Woodland Park Drive, Burlington, Ontario L7N 1L2 Canada; (905) 634-8234 (Joan Muir; Burlington), (905) 844-4160 (Annis Dixon; Oakville), (519) 658-5838 (Margaret Sanderson; Kitchener), (416) 485-7355 (Jerry Ford; Toronto)

  • Pacific Northwest Scuba Challenge Association, 14286 72nd Avenue, Surrey, British ColumbIa V3W 2R1 Canada; (604) 525-7149 (Ron Stead)

  • Persephone Scuba Diving Club, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec H4B 1R6 Canada; Louis Jankowski, Ph.D., (514) 848-3320 (office), (514) 630-1429 (home)



Diving With Disabilities
Bruce Van Hoorn
14960 Penitencia Creek Road
San Jose, CA 95132
(408)258-9789

Dis-A-Dive
Bart Schassoort
3530 Warrensville Center Road
Suite 200
Shaker Heights, OH 44122
(216)241-3483



Open Waters, Paul A. Rollins, Project Coordinator, or Steven Tremblay, Project Director, c/o Alpha One, 127 Main St., South Portland, ME 04106-2622; (800) 640- 7200 (voice or TTY) or (207) 767-2189 (voice or TTY), (207) 799-0355 fax, open_waters@alpha-one.org , http://www.alpha-one.org

The Australian Underwater Federation has published a booklet on teaching disabled divers. It can be obtained from theAUF Office,
PO BOX 1006,
Civic Square, ACT, 2608, Australia.



IAHD, is a non-profit organization for disabled divers.
www.iahd.org and www.iahd-americas.org



Norges handikapfellesskap in Norway,
Dive Training for the disabled.
www.handikap.no
e-mail:tomm.fredriksen@handikap.no

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Wednesday, June 3, 2009

Undercurrent Online Update for Subscribers

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

Dive News

June 3, 2009

You have received this message because you are a current paid subscriber to the print edition of Undercurrent (with subscriber number ,or are a current Online Member (username = ecscubadoc , expiring 2012-12-31 ). Removal instructions are below.

Read or download the current issue*

Check Out Our New Blogs and Forum: We've started running blogs on our website, with updates coming regularly. You can read original pieces by the likes of Burt Jones and Maurine Shimlock, Bret Gilliam, John Bantin, Doc Vikingo and even me, Ben Davison. Or go to our now-public online forum, post your questions, advise others, run your own commentary. Take advantage of the Undercurrent community at Undercurrent .


Belize Island Beachfront Acreage Available:
As Undercurrent has often reported, diving off Saint George's Caye is as good as it gets in Belize. Protected by the Barrier Reef, the nearby reefs are in fine shape with little diving pressure, though it's only a 20- minute boat ride from Belize City. Fred Good, who built the venerable Saint George's Lodge (one of our favorites) in 1977 and sold it in 2004, called to tell us he is selling a large beachfront parcel on St. George's. It's about three acres with 900 feet of beach frontage. It could accommodate a dive resort, up to three family compounds, or be subdivided into 12 building lots, and Fred is willing to actively consult or project-manage because he has already "been there" and "done that." There's a photo of the land above. For more photos and details, click on www.belizebeachfrontproperty.com

Stop Shark Finning in Palau: Diving the famed Blue Corner won't be the same if Palau's politicians approve Senate Bill SB8-44 to permit commercial fishing for sharks and shark finning. A follow-up punch is SB8-50, which would encourage commercial fisheries in Palau's waters by granting them a five-year tax exemption. This would gut the 2004 legislation that banned shark fishing by foreign fisheries, one of the most ironclad laws in the Asia-Pacific area. To stop this nonsense, sign the petition sponsored by SharkSavers.org to keep the bills from becoming law:
http://www.sharksavers.org/get-involved/sign-these-petitions/542-petition-to-palau-stop-senate-bill-8-44-on-shark-fishing.html .

Take a Great Trip on Fiji's Nai'a and Support the Coral Reef Alliance: Join CORAL to celebrate its 15th anniversary by taking a dive trip from November 21 to 28 aboard the Nai'a, the 120-foot luxury liveaboard sailing vessel that Undercurrent readers love. You'll visit spectacular sites near Lomaiviti, Bligh Water and the Namena Marine Reserve. CORAL senior program staff will interpret what's happening underwater and discuss reef ecology and Fijian culture. You'll visit a village where CORAL is working with the community to preserve its reefs. Experience some of the world's best diving while supporting the people who depend on reefs for daily survival. Visit http://www.coral.org/dive_trip to learn more or reserve your spot now - the folks at CORAL tell us the trip is filling quickly.

Divers, Pick Paper Over Plastic: Undercurrent subscriber Hilton Fitt-Peaster (Boulder, CO) told us about a slideshow done by the Pocono Record showing how plastic bags make their way to the ocean and seriously harm - and kill - marine life on the reefs we dive.
(http://www.poconorecord.com/apps/pbcs.dll/article?AID=/20080506/MULTIMEDIA02/80505016)

Are You Unsatisfied with an Equipment Warranty?: We want to know if divers are satisfied with their regulator or computer warranties. Ever have a problem and need to get it resolved under the warranty? Have you had a problem with an item purchased from an Internet seller? Did it or the manufacturer honor the warranty? Has your dive shop handled a warranty problem for you? Let me know your experience, good or bad, by e-mailing your story to me at EditorBenD@undercurrent.org.

Basic Underwater Photography: If you're just getting started or want a refresher course, for $5 you can download this just-published manual by writer and photographer Paul J. Mila. It's got everything you need to get good images by using just your camera's automatic settings. Get details and order the book at www.paulmila.com.

Malaysia Search Called Off for American Diver: Malaysian officials have called off the search for Kenneth Wayne, who disappeared at sea on May 24, because weather conditions were too dangerous for the rescue divers. Wayne, 62, was sailing his 65-foot yacht Sampai Jumpa when it collided with another vessel 31 miles off Kuantan. Wayne, another diver and the three-man Thai crew had to jump into the sea after being rammed by the other boat, which kept on going. The other four were rescued a few hours later by a fishing boat but officials believe Wayne is trapped in the boat, lying some 130 feet deep in the sea.

Florida's Newest Artificial Reef Is Ready For Diving: After a decade of planning and an $8.6 million price tag, the General Hoyt S. Vandenberg was finally sunk on May 27 and is now a public dive site. Forty-four explosive charges sent the 524-foot-long boat 140 feet to the bottom, seven miles south of Key West. The Vandenberg was used to transport WWII troops, bring refugees to freedom, and as a setting for the sci-fi movie Virus. The topmost portion of this former Air Force missile tracker is at 40 feet, making it accessible to divers of all levels. Minutes after it sank, a sea turtle, a pod of dolphins, barracudas and a hogfish checked out the ship. Contact any Key West dive shop for details.

New Flights to Bonaire: American Airlines canceled its weekly flight to Bonaire last month, but Insel Air has stepped in with a weekly Saturday nonstop from and to Miami, starting July 4. Check flight times and prices at www.fly-inselair.com .

Lembeh Straits: Been diving there recently? What did you think of the fish life, especially on muck dives? Was it up to your expectations? Let me know by e-mailing your comments to EditorBenD@undercurrent.org.

Coming Up in Undercurrent: Diving in Puerto Rico and on the Solomon Islands' Bilikiki: are they worth the trips . . . . . should you sauna before a dive? . . . where Hawaii's fish have gone - it's not just the fishermen taking them . . . how and where you can recycle used scuba gear . . . learn to master diving from a kayak . . . why what you eat affects how you dive . . . the best website for determining the dangers of certain overseas dive sites . . . and much more.

Ben Davison, editor/publisher
Contact Ben

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Tuesday, June 2, 2009

Secrets of the Deep


Here is an interesting article in the New York Magazine about diving along the waterfront of New York City. The entire article can be seen at http://nymag.com/news/features/56609/

What lies beneath the surface of New York Harbor? For starters, a 350-foot steamship, 1,600 bars of silver, a freight train, and four-foot-long cement-eating worms.


Commercial diver Lenny Speregen and NYPD detective John Drzal.
Illustrations by Mark Nerys
(Photo: Matt Hoyle)

The steady transformation of New York’s waterfront from wasteland to playground means more of us are spending time along the city’s edge. That can lead a person to wonder: What, exactly, is down there? Until recently, we had patchy knowledge of what lies beneath the surface of one of the world’s busiest harbors. What we did know came largely from random anecdotes, and depth soundings done the way Henry Hudson did them—by rope and lead sinker. This first GPS-era picture comes from the team at Columbia University’s Lamont-Doherty Earth Observatory, who have methodically swept the lower Hudson with state-of-the-art sonar. LDEO’s Dr. Frank Nitsche stitched together their data, along with several other researchers’ work, into this elegant color-keyed map, which we’ve supplemented by talking with sea captains, historians, and the divers pictured above. There’s a whole other city down there. Here and on the following pages is your guide.

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DAN Names New Head of Medical Department


Dr. Nicholas Bird Joins DAN Staff as New Head of Medicine Department

Anyone who has called the DAN® 24-Hour Diving Emergency Hotline or used the non-emergency Medical Information Line knows the outstanding caliber of those who comprise DAN’s medical department. That legacy now continues with the addition of Dr. Nicholas Bird, DAN’s incoming vice president of medical services.

Dr. Bird joins the DAN staff in June. He comes to DAN from the Dixie Regional Medical Center in St. George, Utah, where he currently serves as the medical director of hyperbaric medicine. His acceptance of his new position at DAN follows an intensive and exhaustive months-long search by the organization to find the right candidate for the job.

“We knew the incoming VP would have some large shoes to fill,” said Dan Orr, president and CEO of DAN. “Our retiring VP of Medical Services, Joel Dovenbarger, has served this organization for almost all of its 30 years, and his contributions to its success cannot be measured. We knew it would take a special person to succeed him, and Dr. Nick Bird is that person. He’s a highly qualified and capable physician with extensive experience in hyperbaric medicine. He’s a great fit for our culture and the needs of our medical department, and he’s an active diver who understands and enthusiastically supports our mission and philosophy. We couldn’t have asked for more.”

Dr. Bird’s qualifications include a medical degree from the Royal College of Surgeons in Ireland and the completion of his family medicine residency at the University of Washington at Vancouver, as well as a fellowship in diving and hyperbaric medicine at the University of California at San Diego. He is board certified in Family Practice and Undersea and Hyperbaric Medicine. He served in the U.S. Air Force as a Flight Surgeon and was honorably discharged with the rank of Major, but not before serving as the final Commander of the Base Hospital in Jordan during Operation Iraqi Freedom.

In addition to extensive credentials, Dr. Bird’s character was also highly admired and praised by the candidate selection committee. Said Dr. Brett Hart, a member of DAN’s Board of Directors and the selection committee: “[Our] decision to support Dr. Bird's selection as DAN's new Vice President of Medical Services came down to three things: honor, courage and commitment. Beyond being a capable physician, he consistently demonstrated the moral character necessary to 'do the right thing' in terms of supporting DAN and its mission."

Added Dick Clarke, president of National Baromedical Services and another member of the selection committee: “Dr. Nick Bird brings to DAN solid medical credentials, excellent interpersonal skills and great enthusiasm. DAN's membership will be that much better off as a result of Dr. Bird's close coordination of emergency evacuation and related medical care with all those who work globally on behalf of the injured diver.”

Although the start of Dr. Bird’s tenure at DAN is still a few weeks away, his enthusiasm for his new position is unmistakable. “DAN [is] integral to the diving community,” he said. “As a resource for information, a lifeline for injured divers, a conduit for research and a pioneer of safety training, DAN has distinguished itself as an industry leader.

“I am honored to have been chosen as the new VP of Medical Services and look forward to advancing DAN’s mission of dive safety. As a hyperbaric physician, I am especially interested in DAN’s goal both to establish and enhance the quality and integrity of medical care for divers in remote areas. I have joined DAN at an exciting time in the organization’s development and look forward to rolling up my sleeves and diving in.”

Dr. Bird’s addition to the DAN staff is certainly one reason it is an exciting time at DAN, and we hope you’ll join us in welcoming him both to DAN and the dive industry.

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Sunday, May 31, 2009

Undersea and Hyperbaric Medicine Board Review Course

The University of Pennsylvania School of Medicine (jointly sponsored by DAN) is conducting a Undersea and Hyperbaric Medicine Board Review Course in Philadelphia, PA on 8/21-8/23/2009.

Presented by the Institute for Environmental Medicine/Division of Hyperbaric Medicine, this conference is designed to prepare physicians eligible to take the ABPM of ABEM subspecialty exam in Undersea and Hyperbaric Medicine. Upon completion of the program, learners should be able to:

- Describe the physics of, and human physiological responses to, immersion and high-pressure environments
- Describe the pathophysiology and treatment of medical conditions resulting from diving accidents and injuries associated with changes in pressure
- Understand and describe the medical assessment of fitness for diving process
- Discuss the mechanisms of action, complications, and contraindications of hyperbaric oxygen therapy
- Describe the pathophysiology and treatment of medical conditions in which hyperbaric oxygen therapy is indicated
- Effectively use this overview to prepare for the subspecialty board examination in Undersea and Hyperbaric Medicine

To download a course brochure and registration form, please visit:
http://www.diversalertnetwork.org/Events/Event.aspx?EventID=704

Yours in diving safety,

DAN Medical Services

==================================================================

Saturday, May 30, 2009

To Pee or Not To Pee?

Here is an article that I wrote some years ago for Scuba Diving Magazine.


By Ernest S Campbell, MD

What Makes Divers Want to Pee While Diving?

When diving, I suddenly get the urge to pee, even though I voided only minutes before. Why do I need to pee so soon?
via e-mail

This physiological phenomenon is known as immersion diuresis, a fancy term for your body's response to feeling under pressure. Blood is shifted to your body's core, and the hypothalamus gland thinks this means your total fluid volume is too high and instructs your kidneys to make urine. What can you do to avoid immersion diuresis?

Avoid diuretics like caffeine before you dive.

Intentionally dehydrating yourself might seem like a good idea, but dehydration increases fatigue and predisposes you to decompression sickness.

Try to stay warm. A side effect of your body's response to cold is the production of urine. Wearing a hooded vest under your wetsuit may save you from having to empty your bladder when you least want to. On the boat, stay out of the wind, bundle up and wear a hat.

Be healthy, sober and rested. A variety of over-the-counter and prescription drugs can interfere with your body's heat conservation mechanisms, typically by preventing the constriction of blood vessels near the skin. Antihistamines are particularly suspect. Alcohol is worse.

Although adipose tissue insulates well, allowing fat people to tolerate cold water immersion longer than lean people, it's better to be physically fit.

The Science of Warming Your Wetsuit

You try to hold it in, but can't. Desperate, you pee in your wetsuit. You hope no one will notice. But what can you do? Drink less water?

No, drink more.

The Dehydration Factor

Deliberately dehydrating yourself, in the hope you can hold it until the surface interval, just makes the embarrassment problem worse.

Because of immersion diuresis and your involuntary reaction to cold, chances are you'll have to pee anyway.

Dehydration makes the result stronger in odor and color.

The Embarrassment Factor

There is a well-worn joke that divers belong to two schools regarding peeing in their wetsuit: Those who do and those who lie about it. If you do have to pee in your wetsuit, know this:

If you're well-hydrated, your urine will be nearly clear and odorless. Almost like water. So who's to know?

There's no health risk to peeing in your wetsuit. Most people don't realize that urine is sterile, unless you already have an infection of the urinary tract. The worst you have to fear is a case of diaper rash if the urine stays against your skin several hours, and this too is less of a problem when your urine is diluted. Solution: Open your wetsuit under water and rinse it between dives.

The Warmth Factor

True or false? Urinating in a wetsuit is a quick way to warm up. False, and here's why: You may feel warm initially, but it will actually lower your body's warmth. And, if you're wearing a tight-fitting wetsuit that doesn't flush easily, a semi-dry or dry suit, then this warming-up technique loses a lot of its appeal.

What To Do with a Wetsuit that Stinks

It couldn't be helped. You felt the urge to pee during a dive, and so you did. Now you're afraid your wetsuit will stink. What should you do?

Give it a hot rinse. This is the most important part of regular stink prevention. Walk right past the rinse tank where other divers are busy dunking their suits in the filth rinsed off other gear, and go back to your room at the resort or home and rinse it in hot, fresh water. The easiest way to do this is to take your suit in the shower with you. Hot water is better than lukewarm water for breaking down salts from the ocean and from your body.

Hang it. After rinsing, hang your suit to dry on a wide wooden or plastic hanger, preferably one made for wetsuits. Use a wide hanger to keep the front and back of the suit apart so it can dry more quickly.

Soap it. Every once in a while give your suit a soapy bath. Scrub it well inside and out. Use a sponge on the slick neoprene and a soft-bristled brush on any nylon linings. Just about any kind of soap will work to kill the odor, but some are better than others. The best soaps for the job are commercially available "wetsuit shampoos" (check your local dive store) or a gentle baby shampoo. Next best are regular bath soaps and shampoos. Dish and laundry soaps are too harsh to use regularly on your wetsuit, but will do the job in a pinch. Never have your suit dry cleaned.

Deodorize it. If your suit still reeks, you might want to deodorize it. "Sink the Stink" (www.flinet.com/gulfstream/sts.html) is an all-natural deodorizer made specifically for de-stinking wetsuits.

Friday, May 29, 2009

Diving With Cirrhosis and Ascites

Cirrhosis and Ascites

Here's a query from a scuba instructor:

57 year old male, history of alcoholism & suffering cirrohsis of the liver. Very large, distended belly ( has the largest "outie" belly button you've ever seen! ), but otherwise not obese. Passed the N.A.U.I. pool test better than most of his classmates. Claims his drinking days are past & has non-diving physician, unrestricted approval to participate. No other medical contraindications noted on the standard N.A.U.I. medical questionaire. He is an educated man ( prof. engineer ) with previous sport diving experience years ago... What is your advice?

Answer:
It is highly likely that your diver has ascites (large quantities of free fluid in his abdomen surrounding his organs). In addition to his umbilical hernia (which can rupture easily under these circumstances) which has occurred in response to the excess pressure of the fluid - it is also highly likely that he has esophageal varices or dilated blood vessels in the lower end of his gullet.
Due to the effects of immersion on the blood supply of the body, during a dive blood is shunted from the periphery into the blood vessels of the gastrointestinal tract, liver and spleen. This would cause dilation and possible rupture of the esophageal varices with massive hemorrhage. Add to this the acid reflux changes that occur about the cardia (lower end of the gullet and upper stomach) due to the action of Boyle's law during ascent and we have a set up for rupture of not only the varices but the stomach.

This not just a theoretical possibility but has been reported.

Massive variceal bleeding caused by scuba diving.
Am J Gastroenterol. 2000 Dec;95(12):3677-8.
Nguyen MH, Ernsting KS, Proctor DD.
http://snipurl.com/3s76

Finally, cirrhosis of the liver to the extent that it causes ascites can have significant mental effects of obtundation of the intellect. Hepatic encephalopathy can cause apathy, confusion, disorientation, drowsiness and slurred speech. This alone would be dangerous enough to disallow diving.


Because of what I consider significant risk, I would not certify this person as fit to dive.

Wednesday, May 27, 2009

Diving Accident Management

Diving Accident Management

GestiĆ³n de Accidentes de Buceo
A Power Point Presentation in Spanish


This page is compiled and maintained
by Ernest S Campbell, MD, FACS
scubadoc@scuba-doc.com
Introduction Rescue Resuscitation Position Oxygen
IV fluids Medications InWaterTreatment Transportation Summary

Introduction

It is desirable to have a standard approach to the initial management (i.e. first-aid) of an injured diver.

Coincidentally, a diver may have a non-diving related illness or injury, but in general, symptoms and signs following a dive are likely to be due to that dive.


Rescue

An injured diver must be removed from the water as quickly as possible. If the diver is unconscious and beneath the surface of the water, then they should be surfaced and decompressed in the head upright, normal anatomic position with special attention being paid by the rescuer to the maintenance of a patent airway. Surfacing feet first would delay the initiation of mouth to mouth for a short period. Air would continue to be forced from the lungs by ascent either way you raise the diver. PADI states that head up is the appropriate method. On the surface, the 'do-ci-do' left sided position is what is being taught for mouth to mouth initiation of breathing.

Getting the unconscious diver to the surface as fast as reasonably possible, head up and with the regulator in place would be my recommendation. NOAA does not address this in their new manual and I cannot find any reference to position of retrieval
in the Navy manual.

For other articles about diving safety see http://www.scuba-doc.com/dvsaf.html

A SCUBA diver in this context should have their regulator placed in their mouth, but no attempt at "purging" gas into the injured diver should be made. Divers using rebreathing systems, full-face masks, band masks or helmets should be "flushed-through' with fresh gas, preferably from an alternative emergency gas supply, before swimming them to the surface or recovering them to a platform or bell. Specific techniques for recovery of a diver into and resuscitation of a diver in a bell or hyperbaric rescue vessel are needed and must be practiced.

In the absence of such a platform, the injured diver should be made positively buoyant by removing their weight-belt and perhaps by inflating their buoyancy-compensator (providing it neither limits access for the rescuer nor causes the injured diver to float "face-down'). The injured diver's air tank should be left in-situ as it acts as a keel. The rescuer should adjust their own buoyancy by buoyancy-compensator inflation and not by dropping their weight-belt in case they lose hold of the injured diver and have to recover them again from underwater.

The utility of expired-air-resuscitation (EAR) in the water, either directly or via a snorkel, is debatable. Certainly there is a significant difference between conducting EAR in a swimming pool and in the ocean in this context, effective in-water EAR is only possible with continual practice in the ocean and, in general, an injured diver's best interests are usually served by protecting their airway and getting them out of the water as quickly as possible.


RESUSCITATION

Effective EAR and chest compression ( which obviously should not be attempted in the water ) are life-saving if cardiorespiratory arrest occurs, regardless of the cause of the injury.

Techniques should not vary between the diver who has drowned and the diver who has been envenomated, nor should it be altered for a hypothermic diver (in whom it must never be abandoned until after re-warming has been completed).


POSITION

If any form of decompression illness (DCI) is suspected, then the diver must be laid flat and not allowed to sit-up or stand as this may cause bubbles to distribute from the left ventricle and aorta to the brain. Although such posture-induced phenomena are unusual (rare), they have a very poor outcome. This posture must be maintained until the injured diver with DCI is inside a recompression chamber (RCC). A headdown posture is no longer advocated as it may increase the return of and subsequent "arterialization" of venous bubbles, it causes cephalic-venous engorgement such that subsequent middle-ear inflation (e.g. in a RCC during treatment) is very difficult, it limits access for resuscitation and assessment, and, in animal-model studies it actually retards the recovery of brain function in comparison to the horizontal posture.


OXYGEN

With the exception of oxygen toxicity, administration of 100% oxygen is useful in all diving accidents. Although divers who have pulmonary oxygen toxicity need to breathe a PiO2 of less than 0.6 Bars, many of those who have had an oxygen-induced convulsion will subsequently become hypoxic and need oxygen administration.

To administer 100% oxygen, a sealing anesthetic-type mask is needed (unless a mouthpiece and nose-clip in a conscious diver or an endotracheal tube is used) and a circuit with high gas flow-rates and a gas reservoir must be used. Air breaks, to retard pulmonary damage, may be needed, but should be minimized as must all other interruptions. This is one of the reasons why oral rehydration is not particularly useful.

It is noteworthy that administration of 100% oxygen is the definitive treatment of the salt-water aspiration syndrome and most pulmonary barotrauma, including the majority of pneumothoraces. Indeed, chest cannulation is rarely needed.


IV fluids

As with oxygen, aggressive intravenous rehydration is probably of benefit to all injured divers, even those who have drowned. Certainly, such therapy is of considerable benefit in DCI. Isotonic solutions should be used. Glucose solutions should be avoided as they have been shown to increase damage in neurological trauma.

An indwelling catheter should be inserted (filled with water, not air) and an accurate fluid balance is essential. A persistent poor urinary output despite adequate fluid replacement may indicate either persistent hemoconcentration or bladder dysfunction. Either indicates severe DCI and warrants both bladder catheterization and further fluid replacement.


Medications

There are no drugs of proven benefit in the treatment of DCI. Corticosteroids, anti-platelet drugs, aspirin have been tried without success. Lignocaine has been shown to improve neurological outcome of DCS, particularly when added to oxygen. Diazepam is used to prevent and treat oxygen convulsions and to control vestibular symptoms. It makes titration of treatment almost impossible because it masks the symptoms. Indomethacin is useful only when used in combination with prostaglandin and heparin.

Nasal decongestants and analgesics are useful in many divers with aural barotrauma, and, rarely, antibiotics may be indicated.

Some chemotherapy is useful for marine animal injuries. Many coelenterate (jelly-fish) tentacle nematocysts are inactivated by being doused with vinegar. Fish-sting pain is markedly reduced by immersion of the sting-site in hot water.

Box jellyfish stings
Box jelly fish injury

Box jellyfish
Box jelly fish

Compression-immobilization bandages should be used where possible. Analgesia often requires regional or local anesthetic-blockade and there are specific anti-venoms available for the box jelly fish (Sea wasp), the stone fish and for sea snakes



In-Water Treatment

In-water treatment of DCI is practiced and advocated by some, but is logistically difficult, requires dedicated and effective equipment (e.g. full-face mask; umbilical and breathing system cleaned for oxygen; cradle, chair or platform that can be lowered to the desired depth; warm, calm water without current and dangerous marine animals; and, adequate supplies of oxygen), and clearly should not be used for unconscious, confused or nauseated divers. In general, the diver should be retrieved as quickly as possible to a definitive treatment facility.


Transportation

As for any retrieval of an injured person, stabilization of the diver must precede transportation. This will include resuscitation, delivery of oxygen, insertion of an intravenous line, correction of hypothermia (in divers in the field this should be based on passive re-warming using dry clothes and blankets) or hyperthermia (most likely in closed-diving systems and again the response will need to be specifically developed and practiced), control of hemorrhage and splinting of fractures. A record of oxygen administration and fluid balance is essential.

If DCI is suspected, then the retrieval must not exceed 1000 ft above sea level. A transportable recompression chamber is ideal, but hyperbaric transportations are logistically difficult and considerable time-savings are needed to justify this activity. Many aircraft can be pressurized to "sea-level' during flight, although this usually limits the altitude at which they can fly (and hence makes the retrieval slower and more fuel-expensive). Unpressurized aircraft are intrinsically unsuitable and must fly at less than 1000 feet, which is often not possible. Road transport may also be inappropriate depending upon the road's altitude, contour and surface.


Summary
It is desirable to have a standard approach to the initial management (i.e. first-aid) of an injured diver. An injured diver must be removed from the water as quickly as possible. An injured diver usually requires oxygenation and rehydration. Attention to these, and early adequate retrieval can significantly improve outcome.

Management where no chamber is available

a. 100% O2 by tight-fitting mask in all cases. Continue to treat and transport even if becomes asymptomatic!
b. Oral fluids - 1 liter (non-alcoholic)per hour.
c. IV fluids as soon as possible. Avoid over-loading. One to 2 liters in first hour, then 100 cc per hour. Glucose containing fluids should not be given in the event of neurological DCS. Hyperglycemia increases the chance of neurological damage.
-Ringer's solution without dextrose. Hartmann's, Lactated Ringer's or Normal saline preferred.
-Normal saline
-LMW Dextran (Dextran 40, Rheomacrodex) in saline (alters the charge of the RBC, preventing Rouleaux formation). 500 cc twice daily. Beware of adverse effects of anaphylaxis and pulmonary edema.
d. Medications
1. Glucocorticoids in neurological DCS.
2. Diazepam (Valium) 10-15 mg IV or per rectum to control seizures and severe vertigo.
3. Aspirin is given by some.
4. Lidocaine is being used by some but is still not yet proven.
e. Catheterization for the paraplegic. Use water in the balloon rather than air. Protect pressure points.
f. Pleurocentesis, if indicated.
Transport, transport, transport! Fly in aircraft pressurized at sea level or as low as possible. Beware driving through mountain passes. Have diver accompanied by a person familiar with the facts.


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Monday, May 25, 2009

Immersion Hypothermia and Near-drowning


*This material can also be seen on the website, Scubadoc's Diving Medicine

What is hypothermia and near-drowning?

Hypothermia is a lowered body temperature less than 95 degrees F. Cold water near-drowning is considered a submersion accident often leading to unconsciousness or coma in water temperatures of 70 degrees F or less. A long submersion time is considered 4 to 6 minutes or greater. (See further discussion below)

Why is this important to scuba divers?

Decompression sickness or air embolism often lead to immersion hypothermia and cold water near-drowning as the natural consequences of these diving accidents.

How does this occur?

The body loses heat to the environment by:

  • Conduction, the transfer of heat by direct contact with the water, air or ground
  • Convection, the transfer of heat by air or water that moves away
  • Radiation, the transfer of energy by non-particulate means, heat loss from an unprotected head
  • Evaporation, conversion of water droplets (sweat) into water vapor, thereby absorbing calories of heat.

IMMERSION HYPOTHERMIA

Why is hypothermia dangerous?

Hypothermia may be mild, moderate, or severe. The presentation may range from shivering and piloerection ("goosebumps"), to profound confusion, irreversible coma and death. Significant hypothermia begins at temperatures of 95 degrees F and below. The lowering of the body temperature occurs as the body is robbed of heat by the surroundings. Water conducts body heat away up to 26 times faster than air of the same temperature. Normal body functions slow down with decreasing heart rate, decreasing respiratory and metabolic rate. Thinking is impaired and speech becomes confused. Reflexes are slowed and muscles become stiff and unusable. Then dangerous life-threatening heart rhythms develop which are hard to reverse.

What is a 'diving reflex'?

On immersion in very cold water, reflex actions occur right away. There is sudden hyperventilation, an involuntary gasp, and a varying amount of diving response follows. The diving response is more evident in the very young (infants and toddlers); it consists of a slowing of the heart beat, a decrease or cessation of respiration and a dramatic change in the circulation of the blood with circulation only to the most inner core of the body, the heart, lungs and brain. The casual observer sees this victim as cold, blue and not breathing. These victims appear dead. Cold water immersion victims have been fully resuscitated when treated carefully with a variety of rewarming techniques ranging from warm blankets to complete cardiopulmonary bypass techniques in major hospitals.

Differences in cooling rates occur depending on the age of the victim, sex, body weight, protection worn, nutritional status, general health, specific diseases, water temperature, length of exposure, areas of exposed heat loss, rough versus calm seas, circumstances of the immersion and the "will to live".

*Remember: Immersion hypothermia should be considered part of most dive accidents.

The body loses its temperature in a variety of ways: in the water, after removal and during transport. Cold water immersion victims may look dead but may be entirely resuscitatable.

How can hypothermia victims be recognized?

SYMPTOMS AND SIGNS

1. SHIVERING
2. LOWERED BODY TEMPERATURE
3. COLD BLUE SKIN
4. SLOW HEARTBEAT
5. SLOW RESPIRATION
6. SLURRED SPEECH
7. CONFUSION
8. MUSCLE STIFFNESS
9. CARDIOPULMONARY ARREST

What can be done to assist the hypothermic victim?

TREATMENT

The basic goals of early care are to prevent cardiopulmonary arrest, stabilize the core temperature, then carefully transport the victim to definitive medical care.
1. Removethe patient from the cold environment.
2. Check the ABC's of airway adequacy, breathing and circulation. If acceptable, then we add a "D" as in ABCD: DEGREES - what is the body temperature? A low reading thermometer is commercially available (most clinical thermometers read to 94 degrees F only) and this should be part of an emergency kit. As always, if the patient is not breathing and the heart not beating, standard cardiopulmonary resuscitation (CPR) should be started immediately.
3. Prevent further heat loss. This is done by removing wet clothing, gentle drying of the skin, remove or cut off suits, covering the high heat loss areas of the body, e.g., the head and neck (accounts for 50% of the heat loss), the lateral thorax and groin areas.
4. Gentle handling is a must. As the body rewarms it gets colder first for a short time; this is known as afterdrop.

Why is 'afterdrop' so dangerous?

During this period the heart is very vulnerable to developing life threatening rhythm disturbances. Immediately after rescue the victim should be removed horizontally from the water and kept that way. A litter or stretcher should be used to carry the victim since unnecessary exercising, jumping, climbing or exertion may trigger the heart rhythm disturbance.

Victims may deny they are ill and want to decline medical care, or want to climb into ambulances or helicopters on their own. Remember their judgement may be clouded, and yours should prevail.

Afterdrop can be worsened by certain types of "field treatments", such as a cigarette, a hot cup of coffee and a drink of alcohol, all time-honored treatments. These all prolong the afterdrop and may not help the hypothermic victim recover. They should not be given to hypothermic individuals with core temperatures below 95 degrees F.


COLD WATER NEAR-DROWNING

Are cold water near-drowning victims any different from warm water victims?

Submersion accidents which lead to unconsciousness in waters colder than 70 degrees F occur with regularity. Oxygen needs are much reduced when the body is cold, therefore a permanent brain damage from low oxygen states may not occur. A 60 minute cold water submersion victim has been fully resuscitated. Similar to the hypothermic victims above these nearly drowned individuals appear cold to touch, blue, with no respiration or evident circulation and their pupils are fixed and dilated.

What is the pathophysiology of drowning?

The principal physiologic consequence of immersion injury is prolonged low oxygen level in the blood (hypoxemia). After initial gasping, and possible aspiration, immersion stimulates hyperventilation, followed by voluntary cessation of breathing and a variable degree and duration of laryngospasm. This leads to hypoxemia. Depending upon the degree of hypoxemia and resultant acidosis, the patient may develop cardiac arrest and central nervous system (CNS) lack of blood supply (ischemia). Asphyxia leads to relaxation of the airway, which permits the lungs to fill with water in many individuals ("wet drowning"). Approximately 10-20% of individuals maintain tight laryngospasm until cardiac arrest occurs and inspiratory efforts have ceased. These victims do not aspirate any fluid ("dry drowning").

In young children suddenly immersed in cold water, the mammalian diving reflex may occur and produce apnea,
bradycardia, and vasoconstriction of nonessential vascular beds with shunting of blood to the coronary and cerebral circulation.

The target organ of submersion injury is the lung. Injury to other systems is largely secondary to hypoxia and ischemic acidosis. Fluid aspirated into the lungs produces vagally mediated pulmonary vasoconstriction and hypertension.

Freshwater moves rapidly across the alveolar-capillary membrane into the microcirculation. Surfactant destruction occurs, producing alveolar instability, atelectasis, and decreased compliance with marked ventilation/perfusion (V/Q) mismatching. As much as 75% of blood flow may circulate through hypoventilated lungs.

In salt water near drowning, surfactant washout occurs, and rapid exudation of protein-rich fluid into the alveoli and pulmonary interstitium is observed. Compliance is reduced, direct alveolar-capillary basement membrane damage is seen, and shunting occurs. This results in rapid production of serious hypoxia. Fluid-induced bronchospasm also may contribute to hypoxia.

What are some of the factors relating to surviving cold water near-drowning?

  • Age of the patient - the younger the better the prognosis
  • Length of submersion - the shorter the better
  • Water temperature - the colder the better the survival
  • CPR - if appropriately applied the better the survival
  • Water Quality - the cleaner the better the survival
  • Struggle - the more struggle the worse the results
  • Other injuries - burn, blast, fractures reduce the survival
*Remember: Cold water near-drowning is more survivable than previously thought. Submersions as long as an hour can in some circumstances be fully resuscitated. Cold water may be protective to some body systems as oxygen needs are markedly reduced.

How can I recognize cold water near-drowning?

SIGNS and SYMPTOMS

1. COUGH, CLEAR TO FROTHY RED SPUTUM
2. BLUE SKIN COLOR
3. SHORTNESS OF BREATH
4. CONFUSION TO COMA
5. RESPIRATORY ARREST
6. CARDIAC ARREST

What is the early management of the diver with cold water near-drowning?

Quick Response

1. Remove from the water

2. Do not do a Heimlich Maneuver, as it may induce vomiting and aspiration.

3. ABC's of resuscitation, begin CPR if indicated.

4. Oxygenate.

5. Remove wet or constricting clothing, wet suits, etc.

6. Transport to the nearest medical facility, noting that if this is a diving accident a recompression chamber will be necessary. Decompression sickness or air embolism may have led to the cold water near-drowning in the first place and full resuscitation should be done inside the chamber to be successful.




Thermal Protection and Hypothermia Considerations

Adapted from Martin J. Nemiroff, M.D.

Introduction

Thermal protection is paramount for undersea recreation, effective work, and military warfare needs. Heat loss is accentuated by many factors including the increased thermal conductivity of water as compared to air of the same temperature. The study of immersion hypothermia has increased survivability in downed pilots and aircrew, shipwreck victims, sport scuba enthusiasts, and near-drowned victims.

Where does the body lose heat ?

  • Head, neck, axilla, and inguinal region, for the most part
  • 50 % lost from the head and neck alone heat flux across the skull, blood vessels close to surface
  • Remember children lose heat quicker because of ratio of body mass to skin surface
How does the body lose heat ?
  • Conduction-the transfer of heat by direct contact with water, air or ground
  • Convection-the transfer of heat by air or water that moves away
  • Radiation-the transfer of energy by non-particulate means, heat loss from an unprotected head
  • Evaporation conversion of water droplets (sweat) Into water vapor, thereby absorbing calories of heat
How do we protect these heat-loss areas?
  • Create a micro-climate around body with insulators
    • Waders, gloves, hats, boots, shoes
    • Wet suits made of closed cell neoprene
    • Dry Suits and under garments
  • Clothing In layers, virtues are loose fitting, air trapping, no ligatures, belts, zippers
  • Head coverings
What are some of the factors affecting how fast we lose heat?
  • Water Temperature
  • Outside Air Temperature (OAT)
  • Wind, wind-chill
  • Wave action, sea state
  • Wet clothes versus dry (5 times greater loss)
  • Body habitus
  • Sexual differences
  • Age
  • Air versus water (water 25 times greater loss)
  • Breathing Gas, air helium
  • Activity level, breathing rate
  • Fear, panic
  • Tachycardia
  • Fight or flight
What are some medications and conditions that increase heat loss?
  • Beta blockers
  • Phenothiazines
  • Benzodiazepines
  • Barbiturates
  • Effect of alcohol
  • Cigarettes
  • Metabolic states, thyroid function, or other medications
  • Sepsis
  • Nutritional state
  • Adaptation, "Polar Bear Clubs"
  • Ability to shiver
Have there been any studies about cold immersion?

Modern studies

  • University of Victoria "U-VIC" physical education majors; Determinants of effective working suits,
  • U S Coast Guard Cape Disappointment and Cape May, New Jersey Studies; Special considerations for survival suits, flying suits
Prognostic Factors recently published:
  • JAMA October 10, 1990 Vol 264, No. 14, Hyperkalemia a Prognostic Factor During Acute Severe Hypothermia
  • JAMA ibid above. Editorial Some People Are Dead When They Are Cold And Dead.
*Outlines from Lectures presented at Medical Seminars, May, 1991
*Adapted from M.J. Nemiroff, M.D.

Links
Antarctica Marine Research
Ice Rescue Training
SARBC - Hypothermial
Survival in Cold Water; Minnesota Sea Grant
Drowning

Diving in Polluted Waters


This material can also be seen on the website, Scubadoc's Diving Medicine

Water Pollution

As our rivers, lakes and shorelines become more heavily populated, our diving population has to become more aware of the potentially hazardous presence of pollution in the water. Collectively, our waterways and the sea have been traditional dumping grounds for pollutants of many types and degrees of danger. In 1991, a Los Angeles Times article indicated that 2000 U.S. beaches were closed due to sewage spills. California, as always, a leader had 745 closures with 588 occurring just in southern California. This was quite probably only a fraction of the closures that would have occurred if consistent and regular monitoring was being done across the board. The lack of any standardized program for monitoring our waterways is clearly a problem.



Flush Areas?

Areas of special concern are harbors and similar areas which do not "flush" well; rivers, especially those with high levels of industry on the shores; sewage outfalls which go out to sea but are often overloaded and areas which have their deposits of soft, silty materials dropped as the currents reduce their velocities in dispersal areas. Heavy metal contamination, for example, has caused a major problem with the dredging of a large marina entrance due to the fact that hazardous levels of contaminants including heavy metals, have been identified in the silt and the material cannot be pumped or dumped deeper into the sea as is commonly done. It has been estimated that there are on the order of 15,000 chemical spills that enter our water areas each year in the U.S. alone. The contaminated areas are growing and now include many recreational diving areas as well as scientific study sites and search and rescue operations.

The health consequences of the water pollution have not been quantified by careful study but many local health professionals are concerned with infectious and immunosuppressed patients who are ocean swimmers, lifeguards and divers. Until adequate epidemiologic data is available the recourse would appear to be logically focused upon conservative practices in selecting dive sites and conditions.

This increase in areas of pollution is a worldwide problem and has effected many diving operations. Diving in polluted water requires additional precautions and, in many instances, sophisticated equipment and procedures. Avoiding diving in areas with high potential for pollution, particularly after heavy rains is fundamental in urban or industrialized areas.


Microbial and Chemical Hazards

The problem centers around the fact that microbial and chemical hazards can affect the human body by skin contact, entry through orifices and invasion through the skin. The number of specific hazards and their relative severity is beyond the scope of this presentation. The following list was produced in the NOAA Manual and the details were obtained from the medical literature.

Vibrio - 34 species of this family of bacteria are known and cholera and El Tor vibriones are among those known to be pathogenic to man. Cholera vibriones have recently been found in Santa Monica Bay in California and have raised concerns although it is not known to have produced any disease. Other vibriones may be anaerobic and produce disease states such as purulent otitis, mastoiditis, and pulmonary gangrene. V. Proteus found in human fecal material is a common cause of diarrheal disease. V. Vulnificus is found in sea water.

Enterobacteria
Escherichia - found widely in nature, occasionally pathogenic to man, produces carotenoid pigments and can often be recognized by the orangish pus. E. coli, which has some pathogenic strains is often found in fecal material, and can produce urinary tract infection and epidemic diarrheal disease.

Shigella - produces dysentery
Salmonella - 1000 serotypes, ingestion can produce gastroenteritis including food poisoning, typhoid and paratyphoid.
Klebsiella - can produce pneumonia, rhinitis, respiratory infection.

Legionella - causes Legionnaires disease and Potomac fever. Perhaps inhibited in salt water.

Actinomycetes - causes a "ray fungus" actinomycosis an infectious disease in man which inflames lymph nodes, develops abscesses, can drain into the mouth causing damage to the peritoneum, liver and lungs.

Pseudomonas - pathogenic to man, "blue pus" formed by some pseudomonas infections can lead to a wide variety of infections including wound sepsis, endocarditis, pneumonia, meningitis. It is known to flourish in dark, warm, damp places, i.e. inside hoses, bladder compartments and similar places that are not cleansed after being infiltrated by contaminants.

Cryptosporidiosis is a gastrointestinal disease caused by the parasite Cryptosporidiumparvum, It causes severe diarrhea from getting the parasite in the mouth while drinking or swimming.

Viruses - infectious agents which can result in fevers (frequently severe), mononucleosis, and a wide range of disease states.

There are seven currently recognized hepatic viruses:

Type of virus
Route of Transmission
Comments
A
Fecal-oral
Common, no chronic component
B
Blood-borne
DNA virus, 5-10% chronic
C
Blood-borne
RNA virus, 50-80% chronic
D
Blood-borne
RNA, needs prior Hep B to exist
E
Fecal-oral
Asian, rare USA
F
Fecal-oral
Existence debated
G
Blood-borne
Being evaluated clinically
Parasites - many types with all manner of effects, all bad, can are found in polluted water. Cercaria, shistosomes are examples.

Chemicals - There are over 15,000 chemical spills in the U.S. waterways each year and many of these are releasing chemicals that are incompatible with man and the equipment that is worn.

As detailed information becomes available on this issue the divers will become sensitized to the need for preventive measures before, during and after diving. At present the scientific and public safety diving communities are developing techniques for isolating the diver from the potential problems and decontaminating all exposed elements of the diving equipment. It appears eminent that the recreational community will feel the need to exert greater care in the future.

It is becoming increasingly important to develop an understanding of the variations in the local conditions to which individuals expose themselves. Some areas become particularly hazardous following heavy rains, hot weather and windstorms. Local health authorities can usually be called for advice regarding any tests that have been performed and the results. They should also be able to identify areas of high concentrations of pollutants that should be avoided.


What Measures can be taken?

When diving in areas where pollution is suspected or expected the following issues are worthy of evaluation.

1. The individual diver should consider the need for appropriate vaccinations and inoculations. Many of the diseases can be avoided if the individual has taken the appropriate "shots". Some that should be considered are:
Hepatitis A, B and C. (There is no vaccine currently available for Hepatitis C).
Cholera,
Polio
Tetanus.
Typhoid, Smallpox and Diphtheria

2. Pollution and filth are often associated. If the water contains obvious trash and garbage it is quite probably an unhealthful diving environment and another location should be selected. If the water looks nasty it probably is nasty!!

3. Many diseases have an incubation period before they exhibit symptoms. Medical advice is as close as the phone and early diagnosis and treatment can sometimes be improved if the Doctor understands that an individual may have been submerged in polluted water.

4. Information on chemical spills can be obtained from the Chemical Transportation Emergency Center (1 800 424 9300 US).

5. "When in doubt- Check about"


What does NOAA recommend?

A basic procedure if one has to dive in high risk water involves reducing the exposure of the diver. NOAA has pioneered a sophisticated SOS (suit over suit) system that will virtually isolate the diver from any contact with the water. This system is somewhat complex inasmuch as it requires complete system integrity from the times the diver dresses out until the system has been decontaminated following the dive. Strict procedures are followed to ensure that the divers body does not contact the fluid in which it is immersed.

Previously, many public safety divers wore a single dry suit and a full face mask during their dives. However, Stephen Barsky now states that "Full-face masks only provide minimal protection and should only be used in environments where the pollutants are known, and do not pose a threat of death or permanent disability. In environments where the pollutants are not known, or where they lead to death or permanent disability, a helmet should be worn connected to a mating dry suit with mating dry gloves. This is considered the standard today." (See Reference below)

If good seals are involved and the diver is effectively rinsed, scrubbed down and rinsed again prior to breaking any existing seals, the probability of exposure to the pollutants can be minimized. Special care must be taken to clear hoses and fittings that interface with the life support system. A failure to rinse bladders and hoses which may later be linked to the divers mouth or lungs could provide a path to the host days after the dive. The use of snorkels, alternate air sources, oral inflation devices and hose connections should all be given careful attention since the can carry contaminants directly into the mouth. Positive pressure, "self bailing" breathing systems have definite advantages in that they resist flooding.

Recreational divers maybe well advised to place their regulator in their mouth and their mask over their nose before entering suspect water and keeping it there until they have safely exited the water where they can remove the regulator without needing to replace it.

Polluted water is a fact of our lives. The degree of pollution can only be mitigated through education and the "upstream" elimination of the sources of the contaminants. The attitude that careful rinsing of diving gear is a waste of time "cuz its just going to get wet again next time it is used" should probably be replaced with the attitude that one should begin every dive with clean gear.


References:
Glen Egstrom, Ph.D

Medical Seminars, Inc. 1992

Colwell, et.al. Microbial Hazards Of
Diving In Polluted Waters, Maryland Sea Grant
Publication UM-SG-TS-82-01.

Diving in High-Risk Environments, 3rd Edition
by Steven M. Barsky
Amazon.com
Paperback - 197 pages 3rd edition (December 15, 1999)
Hammerhead Press; ISBN: 0967430518