A nonthrombogenic diffusion membrane for continuous in vivo measurement of blood gases by mass spectrometry

Abstract
A heparinized silicone rubber diffusion membrane covering a 22-gauge stainless steel intravascular cannula allows continuous in vivo measurement of blood gas tensions by mass spectrometry in an unheparinized animal or patient. This system has been tested in the aortas of a series of five dogs for periods up to 24 hr, and nonheparinized controls have been used in two dogs. The controls showed evidence of membrane coagulation, but the heparinized membranes were non-thrombogenic and provided quantitatively accurate measurements of Po2 and Pco2 throughout. nonthrombogenic materials; blood gas tensions; oxygen; carbon dioxide; monitoring devices Submitted on July 18, 1969