Physical and Chemical Explanation of Decompression Illness and its solution.

In decompression sickness, the reverse process of Nitrogen Narcosis occurs. As the diver ascends to the surface the ambient pressure decreases and therefore the partial pressure of the nitrogen, causing it to go from liquid to gaseous state again. This causes no major complications, as only micro-bubbles of nitrogen travel through the bloodstream to the lungs to be exhaled. However, if the diver rises rapidly because of such a drastic change in pressure, the nitrogen bubbles will collect together forming larger bubbles in the bloodstream, which will later travel to different tissues causing problems.
This commonly occurs as a result of violating or approaching too closely the diving table limits.
When high levels of bubbles occur, complex reactions can take place in the body, usually in the spinal cord or brain. Numbness, paralysis and disorders of higher cerebral function may result.

Solution:
Treatment involves compression to a treatment depth, usually 60 feet, and breathing high oxygen fraction gases at an oxygen partial pressure of between 2.8 ATA (atmospheres) and 3.0 ATA.

References:
Thalmann, E. (2002). Decompression Illness: What Is It and What Is The Treatment?. 16/01/2017, de Divers Alert Network Sitio web: http://www.diversalertnetwork.org/medical/articles/Decompression_Illness_What_Is_It_and_What_Is_The_Treatment