COMPOSITE, HOLLOW FIBER MEMBRANE OXYGENATION DEVICE

THE ACCEPTANCE OF EXTRACORPOREAL OXYGENATION DEVICES BASED ON GAS TRANSFER THROUGH A MEMBRANE WILL DEPEND TO A LARGE EXTENT ON THE AVAILABILITY OF SIMPLER, EASIER TO USE, SAFER,AND LOWERCOST DEVICES. OXYGENATORS USING MICROPOROUS HOLLOWFIBERS HAVE COME INTO WIDER USE THE LAST FIVE YEARS. THEY PRESENT MORE MEMBRANE SURFACE TO BLOOD AND GAS PHASES FOR EQUIVALENT VOLUME AND DO NOT REQUIRE A SUPPLEMENTAL SECONDARY FLOW FOR ADEQUATE GAS TRANSFER. THESE DEVICES DO,HOWEVER, SUFFER FROM THE REAL AND POTENTIAL PROBLEMS ASSOCIATED WITH ALL MEMBRANE OXYGENATORS MADE FROM MICROPOROUS MATERIALS-POSSIBLE BLOOD DAMAGE DUE TO MICROBUBBLE INTRUSION, EXCESSIVE WATER TRANSPORT AND SEEPAGE, AND A LACK OF SELECTIVITY IN EXCHANGING OXYGEN AND CARBON DIOXIDE. THIS PROPOSAL SUGGESTS AN IMPROVEMENT TO THE PRESENT STATE-OF-THE-ART, MICROPOROUS-BASED HOLLOW-FIBER OXYGENATORSTHAT ELIMINATES ALL THE ABOVE PROBLEMS BY DEVELOPING A COMPOSITE PERMSELECTIVE/MICROPOROUS HOLLOW FIBER DEVICE OF OPTIMUM GEOMETRY AND MEMBRANE CHARACTERISTICS. THE OPTIMIZED HOLLOW-FIBER GEOMETRY WILL BE COMBINED WITH PAS MATERIALS THAT HAVE BEEN SHOWN TO HAVE SUPERIOR PERMEABILITYTO CARBON DIOXIDE AND OXYGEN AND HIGH BIOCOMPATIBILITY WITH BLOOD.