THE EFFECTS OF SOME HYDROPHOBIC GASES ON THE PULMONARY SURFACTANT SYSTEM

1 Decompression from exposures to raised ambient pressure of sulphur hexafluoride, carbon tetra-fluoride, hexafluoro-ethane and nitrous oxide results in the formation of dense foam and pulmonary oedema. 2 The degree of pulmonary oedema produced is dependent on the exposure pressure, although the exposure time required is short in comparison to tissue saturation times. 3 The effect is not prevented by atropine, ephedrine or hydrocortisone. 4 The effect is also produced in vitro by saturated solutions of halothane, chloroform and ether. 5 It is suggested that the mechanism of action is physical with the physico-chemical factor involved being a differential partition of these gases within the surfactant: membrane complex.