I wholly agree with Dr. Bill. The reality is that, although descended from inhabitants of the sea -- we are no long physiologically sea creatures . . .
From today's NYT article (http://www.nytimes.com/2013/11/19/s...t-fate-72-meters-down.html?src=me&ref=general):
"Francisco Ferreras-Rodriguez of Cuba, who set a world record for diving without the aid of breathing gear, plunged in 1996 to a depth of 436 feet. Studies later showed that the seas pressure at 400 feet compressed his chest size by more than half lowering it from a circumference of 50 inches at the surface down to 20 inches.
Marine mammals that routinely dive deep have lungs that can collapse entirely. Some have chests built like accordions designed to fold. Whales, seals, and other deep-diving mammals store oxygen not in their lungs but in networks of powerful muscles."
and,
"Blood from the legs and arms gets forced into the heart and chest cavity, which in humans is kept from total collapse by the bony rib cage and other chest structures. Typically, the body of an adult male holds roughly five liters of blood, and studies have shown that the outer pressure on divers can send up to one liter of excess blood flowing into the chest cavity.
At first, that pooling of blood around the heart and lungs is a good thing, supplying the diver with life-giving oxygen. But as the pressures rise, the fragile human body gets transformed into a kind of pressure cooker that is squeezed hard on all sides by extreme water pressure on the outside and blood pressure on the inside.
Dr. Ponganis said the added pressure in the circulatory system radiated through the lungs and could force blood vessels and capillaries in the lungs to burst and bleed in the worst case, slowly filling the lungs with blood.
This doesn't seem to me to be a matter of mere physical training, conditioning, or acclimatization -- but more so, one of the limits of our human physiology.
Nonetheless, this is a tragic outcome and my condolences to Mr. Mevoli's many friends and his family.
