In the 1600’s,
Robert Boyle discovered that as a pressure surrounding a gas is increased, its volume is decreased—the
relationship between pressure and gas are inversely proportional. Further expanding
on this, in the 1800’s, J. W. Henry proposed that the concentration of a solute gas (one
that is dissolved) in a solution is directly proportional to the partial pressure of that gas above the solution. In other words, when under an increase of pressure, gases dissolve in
liquids to form solutions at an equilibrium between the dissolution and the pressure. Greater pressure (ATA) directly
dissolves more gas (oxygen) in a liquid (plasma, other body fluids).
Charles' Law focuses on the relationship between temperature and volume, finding that a change in
temperature will cause a change in volume of a gas. If temperature increases, volume increases and as temperature
decreases, volume decreases.
Gay-Lussac
worked with Charles and found that the pressure of a confined gas is proportional to temperature or as the pressure increases, the temperature
increases.
Some people report that during a hyperbaric
oxygenation treatment, as the chamber is taken to pressure, they feel warmer inside the chamber until the prescribed
pressure is reached. The temperature then equalizes. As the pressure is decreased at the end of the treatment,
they feel cooler.
Pascal's Principle
states that a force on any part of a confined liquid or gas pushes uniformly on all of the liquid or gas. Pressure is transmitted
undiminished in an enclosed static fluid.
Dalton's Law describes
the relationship to the pressure of individual gases in a mixture of gases to the total pressure of the gas mixture. The
part of total pressure exerted by only one gas in a mixture is the partial pressure. The sum of all of the partial pressures
equals the total pressure.