Patent ID: 7067060

Claim:
In a blood dialysis system including a source of substitution fluid and a blood dialysis machine, a hemodiafiltration device comprising: a source of a first dialysate fluid having a first pH and a source of a second dialysate fluid having a second pH; a first dialyzer including: a first semi-permeable membrane partitioning said first dialyzer into: a first blood compartment having a first blood inlet which receives blood to be cleaned and a first blood outlet which expels partially diafiltered blood; and a first dialysate compartment having a first dialysate inlet connected to said source of the first dialysate fluid and a first dialysate outlet, said first dialysate inlet for accepting said first dialysate fluid having a first pH; a chamber for mixing said partially diafiltered blood with substitution fluid from said source to obtain a blood/substitution fluid mixture; and a second dialyzer including: a second semi-permeable membrane partitioning said second dialyzer into: a second blood compartment having a second blood inlet which receives said blood/substitution fluid mixture and a second blood outlet which expels diafiltered blood; and a second dialysate compartment having a second dialysate inlet connected to said source of the second dialysate fluid and a second dialysate outlet, said second dialysate inlet for accepting a second dialysate fluid having a second pH, said first pH of said first dialysate fluid being greater than said second pH of said second dialysate fluid.