It has been shown by Clowes that the construction of a membrane oxygenator is practicable and that thin Teflon membranes permit greater passage of oxygen than any others now available.1 Clinical studies with the membrane oxygenator have utilized a polyethylene membrane 0.0008 in. thick. In such an oxygenator the passage of both oxygen and carbon dioxide apparently were satisfactory. According to Clowes, carbon dioxide was found to diffuse from blood through Teflon at rates proportional to oxygen uptake. Limited studies in the laboratory with a small modified Clowes oxygenator led us to the belief that carbon dioxide, at reasonable pressures, diffuses to an inadequate degree through Teflon membranes. This belief appears to be substantiated by the following studies.
Materials and Methods
Oxygen transfer through Teflon membranes 0.00025 to 0.004 in. thick was studied by means of a platinum polarograph. The Clark electrode2 was used, and the amplified electrode