Plasma Filtration Detoxification on Hepatic Patients: Its Optimal Operating Conditions

Abstract

Since 1974 [8], the system of on-line plasmapheresis by membranes with the treatment of plasma by various reactors has been studied extensively in vitro [1, 4], ex vivo on animals [10, 11], and recently has been applied clinically [2, 3]. A similar system was also applied clinically on hepatic failure patients by Yamazaki and Inoue in 1977 [12]. To date, eight patients have been treated with this method at the Cleveland Clinic Foundation. Three patients were suffering from hepatic failure, two from intense pruritus due to primary biliary cirrhosis, and the remaining three had hepatic failure secondary to complications following cardiac surgery. Thirty procedures were performed for a total of 211 hours with treatment times ranging from 1 to 12 h. Detailed clinical results will be reported separately. Cellulose acetate hollow fiber (CAHF) filters (Asahi Medical Co., Ltd., Tokyo, Japan) have been used as the plasma filters, and both 90 gm dry weight of an anion exchange resin denoted BR-601 and 250 gm dry weight of coated charcoal (Hemosprba, Asahi Medical Co.) were used as sorbents. Over the course of our investigations various styles of the CAHF plasma filters have been studied. The membrane has the following nominal properties: inside diameter 370 microns, outside diameter 690 microns, porosity 84% and nominal pore size of 0.2 microns. Three major styles of devices have been available for study: the S-type, N-type, and Plasmaflo that differ in module dimensions and the number of fibers. Present work is being done exclusively with the Plasmaflo devices.