Under the Sea - Heart Surgeon Dives Into Underwater Medicine 
(Posted 5/24/06)

By day, cardiothoracic surgeon Richard Sadler, M.D., spends hours in Genesis Operating Rooms, immersed in fighting heart and lung disease.  Get him on vacation, though, and you'll find him diving in some remote ocean location, immersed in the fascinating field of undersea medicine.  

His passion for diving began as a hobby at age 17, when he became a certified diver.  It grew into a sport shared by his entire family.  Over the past couple of years, it has become his medical sub-specialty. 

He has undergone extensive training and attained certification as a certified diving medical examiner.  This year, he's among an elite group of physicians to become board-certified in Undersea and Hyperbaric Medicine from the American Board of Preventive Medicine.  Only 223 such certifications have been issued since 2000, according to the board's Web site. 

"I love everything about being underwater and the high pressure, hyperbaric environment," Dr. Sadler says.  "My daughter dives.  My wife (internist Nancy Sadler, M.D.) dives. Fourteen of the 17 members of my extended family dive.  When everyone in your family dives, you want to know how to keep them safe and understand the medical implications." 

Make no mistake.  This isn't just diving first aid.  It's extreme medicine to prevent and treat illness and injury in environments of increased ambient pressure.  Add the science of hyperbaric oxygen therapy and the health threat of venomous sea creatures, and there's an ocean of challenging medical science to learn, Dr. Sadler says. 

Hyperbaric medicine deals with the use of high-pressure oxygen - via a hyperbaric chamber - to raise blood oxygen content and treat certain diseases, burns, tissue infections, problem wounds and carbon monoxide poisoning.  For divers, hyperbaric oxygen is the specific cure for decompression illness and the life-saving treatment for air embolisms. 

"Decompression illness or arterial gas embolisms occur because there are gases like nitrogen and oxygen saturating your blood," Dr. Sadler says.  "If you rapidly lower the pressure, the gases do not have a chance to slowly come out through the lungs.  Instead, they just fizz over into your bloodstream.  That "fizzing over" is what we call the bends or decompression illness.  Commercial and Navy divers actually call it fizzing. 

"The analogy is taking a bottle of soda pop, shaking it up and stimulating the gases and solution inside.  If you pop the top off all of a sudden, you decrease the pressure and 'boom' it explodes over.  That's exactly what happens in your bloodstream if you come up too fast or dangerously decompress." 

NOAA Diving Program
Two years ago, Dr. Sadler's intellectual pursuits landed him at the NOAA Diving Center in Seattle, a program administered by the U.S. Department of Commerce, National Oceanic and Atmospheric Administration.  There, along with classmates that included physicians from NASA and scientists from Japanese and Turkish space programs, he underwent an intense two-week, diving medical officer course.  He learned how to use hyperbaric chambers for diving accidents, interact with hostile sea life and treat poisoning from marine bites and stings. 

"Without a doubt it was the most intense and gratifying continuing medical education course I've ever taken," Dr. Sadler says.  "We went into pressurized tanks that simulated different ocean depths.  They took us down to 100 feet, and ran us on 1 percent oxygen to demonstrate that you can survive the pressure on low oxygen levels.  When you come up to the surface, you have to bring back the oxygen at a certain rate so that when you get back to the surface you don't kill yourself." 

Ask him how a doctor from Iowa can have much use for diving medicine, and he'll tell you about the time last summer that he, his wife and daughter participated in the rescue attempt of a 75-year-old woman who ultimately drowned off the coast of Maui.  Statistics show more and more U.S. diving injuries are occurring inland. 

"People dive on vacation in the South Pacific or Hawaii and then get right on a plane and don't realize that it's dangerous after diving," he says.  "They start having decompression sickness while they're in the plane, then they land at home and need medical attention." 

Aside from that, diving in pristine marine sanctuaries and the joy of learning more about the world are reasons enough, he says.  "The field of diving medicine and the whole physiology of diving are so fascinating and challenging that I wanted to keep pursuing it." 

-- Story by Linda Barlow, Genesis