Solubilidad, molaridad y actividad osmótica de los gases / Solubility, molar and act Osmotic activity in the gases

ABSTRACT

The principles of gas-induced osmosis, demonstrated in the 1979's, may indicate the orgin of fluid shifts between the intraa and extravascular compartments of an organism that is experiencing changes in atmosperic pressure (e.g. during the compression and decompression of deep-sea divers) or switching the inert gas of a breathing mixture even though there is no change in environmental pressure. In phisiological conditions there exists a permanent gradient of CO2 and O2 between the peripheric tissues and the blood which produces a "pulling" of fluids in opposite directions. The osmotic pressure of O2 respirated at 100 and at 2 ATA of pressure, the equivalent of 8,4 of the osmotic pressure of plasmatic proteins, is a value not compensated by CO2. The potencial for osmotic pressure to be induced by O2 is elevated with an increase in capilar permeability. This entails the loss of macromolecules at the instertital space, which diminishes the oncotic pressure of the plasma and makes the fall of O2 in the tissue even more evident by the efects of oedema. In these cases, gas-induced osmosis could have a decisive importance in the reabsoption of the oedema in the soft tissues, effectively breaking the vicious cycle between hypoxia and oedema