Hollow fiber-type artificial lung having enclosed heat exchanger

Claim 1

A hollow fiber-type artificial lung having an enclosed heat exchanger comprising: (a) an oxygenator section, said oxygenator section including: a first housing; a bundle of a multiplicity of hollow fibers for gas exchange, said hollow fibers having mean pore sizes of 200 to 2,000 angstroms and being gas permeable and liquid impermeable, said hollow fibers being physically separated from one another and arranged side by side within and along the longitudinal direction of said first housing; first and second walls liquid-tightly carrying said hollow fibers at the end portions of said hollow fibers with said end portions of said hollow fibers left open, said first and second walls defining an oxygen chamber with the inner wall of said first housing and outer wall surfaces of said hollow fibers; oxygen inlet and outlet means communicating with said oxygen chamber; and a first blood circulation opening communicating with an interstitial space of said hollow fibers externally of said first wall; (b) a multiple tube-type heat exchanger section, said heat exchanger section including: a second housing; a multiplicity of tubes physically separated from one another and arranged side by side within and along the longitudinal direction of said second housing; third and fourth walls liquid-tightly carrying said tubes at the end portions of said tubes, with said end portions of said tubes left open, said third and fourth walls defining at heat exchange medium chamber with the inner wall of said second housing and the outer wall surfaces of said tubes; heat exchange medium inlet and outlet means communicating with said heat exchange medium chamber; and a second blood circulation opening communicating with an interstitial space of said tubes externally of said fourth wall; and (c) a blood chamber defining means defining a blood chamber and coupling said oxygenator section directly to said heat exchanger section in substantially coaxial relation and with said open ends of said hollow fibers in face-to-face relation with said open ends of said heat exchanger tubes, said blood chamber being interposed between said second wall of said oxygenator section and said third wall of said heat exchanger section and said second and third walls defining end walls of said blood chamber, said blood chamber communicating said oxygenator and heat exchanger by facing end openings in said hollow fibers carried by said second wall and end openings in said tubes carried by said third wall, and said blood chamber serving as a blood flow buffer chamber so that the processing capability of said oxygenator section and that of said heat exchanger section may be determined independently of each other.