DCS What is Undeserved in “Undeserved Decompression Sickness”?
by Neal W. Pollock, PhD
This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.
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Divers still seek comfort in the notion of the “underserved” hit to explain unexpected incidents of decompression sickness. “Hey, my computer said I was fine.” NOT. Here diving physiologist Dr. Neal Pollock exposes the fault in this notion. While decompression algorithms take into account the divers’ profiles, i.e., time and pressure, there are a multitude of factors that can potentially impact divers’ decompressions, as the author explains. Once divers’ reject the escapism that accompanies the ‘undeserved’ label, they can get on with the important business of diving and giving adequate consideration in their deco planning.
Spoiler Alert: the most undeserved element in the title is the word “undeserved.”
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Describing cases of decompression sickness as “undeserved” generally speaks more from an emotional perspective than a rational one. The driving factors are typically faith in imperfect tools and a desire (conscious or unconscious) to shift responsibility.
Decompression algorithms rely almost exclusively on pressure and time data to predict effects. Enticing pictures can be painted on the authority of any algorithm, but the reality is that all rely on limited input to interpret complex situations for people who are not uniform. Modern decompression models are important constructs that can help us to dive safely, but the products are rudimentary from a physiological perspective, without sufficient sophistication to deserve unquestioned trust.
The dive profile is almost certainly the most important determinant of gas uptake and elimination, but the truth is that we do not yet have sufficient data to quantify the impact of many of the variables that can influence outcomes (Pollock 2016). Instead, algorithms rely on simple measures and mathematical bracketing with the hope of covering the contributing factors. The problem is not in doing this; the problem is in being surprised when the outcome is not what was expected.
For the remainder of this GUE In Depth article use the link below.
What is Undeserved in "Undeserved Decompression Sickness"? - InDepth (gue.com)
