Raising the Dead: Nightline Fri

[Vtach]

I think that anyone pushing these sort of limits has an understanding of what MAY happen but it is still no less a tragedy especially when it's someting relatively simple that snowballed into a lethal event (which sounds like a common thread in many diving accidents).  It's an even bigger tragedy if no one learns anything from this unfortunate event. 

My first thought about this was, "DAMN, 880ft!"  But watching that video made me really think.  You can plainly see how a relatively simple task can turn into catastrophe.  Task loading, anxiety, respiratory rate, heart rate, oxygen demand, work of breathing, CO2 retention.....  This is an event that could happen to any diver.  Diver at 100 feet with low vis, add 1 poorly functioning regulator, add some tunnel vision, add some narcosis, throw in some exercise and VOILA! CO2 retention, now where it goes from here depends on the diver.  Now obviously 880 ft (27.6 ATA of pressure) will create a much quicker physiological response to this than 100ft (4 ATA) will, but if left to progress, the results will be similar. 

For those deep air divers (been there, done that, no more), I remember reading an abstract that described how our airway anatomy is unable to adequately hyperventilate partial pressures of air (21/79) over 7 ATA due to the density of the gas at those PP's.  So, no problem when things are going well and you have a normal respiratory rate, but start to work a bit and you could find yourself following the same track.  I looked for the link but couldn't find it. 

Here's another good one for those who like "technical" reading, enjoy.