Hemofiltration refers to the use of a transmembrane hydrostatic pressure (THP) gradient to induce filtration of plasma water across the membrane of the hemofilter. The solute accompany their solvent (solvent drag) across the membrane resulting in the convective transport of small and medium-molecules (< 50000 Da). Haemofiltration is an alternative form of renal replacement therapy where solute removal is activated only by convection, rather than diffusion as in haemodialysis Hemofiltration has superior ´middle-molecules´ clearance but poor clearance of small molecules compared with diffusive hemodialysis
Several studies have shown that synthetic membrane materials are more effective than cellulosic materials and that hemofiltration is more effective than hemodialysis