from
The Collaborative International Dictionary of English v.0.48
Caisson disease \Cais"son dis*ease"\ (Med.)
A disease frequently induced by remaining for some time in an
atmosphere of high pressure, as in caissons, diving bells,
etc. It is characterized by neuralgic pains and paralytic
symptoms. It is caused by the release of bubbles of gas,
usually nitrogen, from bodily fluids into the blood and
tissues, when a person, having been in an environment with
high air pressure, moves to a lower pressure environment too
rapidly for the excess dissolved gases to be released through
normal breathing. It may be fatal, but can be reversed or
alleviated by returning the affected person to a high air
pressure, and then gradually decreasing the pressure to allow
the gases to be released from the body fluids. It is a danger
well known to divers. It is also called {the bends} and
{decompression sickness}. It can be prevented in divers by a
slow return to normal pressure, or by using a breathing
mixture of oxygen combined with a gas having low solubility
in water, such as helium.
[Webster 1913 Suppl. +PJC]