Blood Detoxification by Membrane Plasma Filtration

Abstract

The recognition of macromolecule abnormalities in various metabolic or immunologic related disease states has led to the use of plasma exchange for therapeutics. Limitations of plasma exchange, however, exist. Membrane plasma filtration provides a practical alternative. Solute removal can be made selective by the choice of operating conditions as temperature and the selection of the membrane/module design. The optimal temperature range is a function of the plasma type, solute concentrations and membrane system. Operation at below physiologic temperature (cryofiltration) is particularly suited for the removal of cold aggregative solutes, while operation at near or above physiologic temperature is more suited for the separation of solutes having large size differences at normal physiologic temperature. Membrane filtration is simple and safe to perform, is more selective than plasma exchange, does not require plasma product infusion and is more versatile than selective sorption in its applications.

Current Topics on Cryofiltration Technologies

“…While therapeutic plasmapheresis has been widely used over the last 40 years, cryofiltration apheresis has only been developed in the past 20 years. However, over these last 20 years, advances in cryofiltration have been targeted to treat specific diseases such as cryoglobulinemia (1–5). As in traditional plasmapheresis, the plasma is separated from the whole blood components using either centrifugation or primary membrane plasma separators.…”

Membrane Processes for Plasma Separation and Plasma Fractionation: Guiding Principles for Clinical Use

“…Plasmas from different disease states vary in their concentration of macromolecular weight constituents that will affect performance. Using one membrane module type, Table 4 compares the results (53) of the plasma volume processed and mean sieving of select plasma solutes at a filtration temperature of 4°C, appreciably below ambient temperature. The volume of plasma processed to a transmembrane pressure of 300 mm Hg varied with the type of plasma.…”