| Imported post
Phill gives an answer in terms of dissolved nitrogen exchange between tissues which may be part of the picture. Decompression illness is complicated and not fully understood, so categorical answers are not possible. Modern thinking is that microbubbles form on most ascents. Once formed on the first ascent, they will be squeezed by a subsequent descent, but may not be completely dissolved. Microbubbles are thought to affect nitrogen absorption and release and to act as seeds for larger bubbles on a subsequent ascent. In addition, the capillaries in the lungs are thought to trap and filter out microbubbles from the blood. A further danger is therefore that microbubbles trapped in the lung capillaries may be compressed by a subsequent descent to allow them to pass through the lungs to the heart to be pumped into the arterial circulation direct to the tissues, particularly the brain, possibly clumping together on the way.
Ian W |