Hollow Fiber Membrane Application for Blood Treatment

Hollow fiber membranes have been widely used for extracorporeal blood treatment ranging from an artificial kidney, plasmapheresis to oxygenator. In particular, the artificial kidney is currently an established therapeutic modality for renal failure. Hitherto, various hollow fiber membranes have been developed and become commercially available, and thus in Japan alone about 15 million-m2 hollow fiber membranes have come to be used a year. In view of such a trend, many studies are being carried out to elucidate the interactions between the membrane and blood, such as antithrombogenicity or complement activation. In addition, modification of membranes is being investigated in order to prevent complications of long-term dialysis patients. The hollow fiber membrane is also employed in therapeutic plasmapheresis which aims to treat intractable diseases by removing pathogenic macromolecules in plasma. There are several clinical procedures which enable selective removal of harmful substances in blood with a combination of some membranes of different pore sizes. The membrane oxygenator consisting of microporous, hydrophobic hollow fibers is routinely used as a temporary alternative to the patient lung during open-heart surgery. The membrane method is considered to be superior to the conventional bubble type oxygenator because of less deleterious effects on blood components. Also, extracorporeal membrane oxygenation has been developed as a long-term assist in the treatment of respiratory insufficiency patients.