Selective Removal of Plasma Proteins by Double-Filtration Plasmapheresis in Canine Blood: An Ex Vivo Study and Retrospective Report of In Vivo Clinical Treatments in Three Dogs

Double-filtration plasmapheresis (DFPP) is a plasma-exchange modality that allows selective clearance of high-molecular-weight proteins, potentially minimizing albumin loss and the need for volume replacement. Reports concerning DFPP use in dogs are scarce. This study evaluates the quantitative net loss of different plasma proteins fractions in an ex vivo model using canine blood processed via DFPP. DFPP treatment with INUSpheresis® processing 1.5, 2, and 3 plasma volumes (PVs) was performed. Plasma proteins fractions were measured in the reservoir blood bag at baseline (pre-treatment) and in the effluent bag at the end of each target PV exchanged to calculate the net loss of selected plasma proteins. At 1.5 PV, net globulin and albumin loss was 41 and 25% respectively. At 3 PV, net globulin and albumin loss was 47 and 40%, respectively. Fibrinogen concentration was unmeasurable low in the reservoir blood bag after processing 1.5 PV. INUSpheresis® allows selective plasma proteins removal, with a sparing effect on albumin at 1.5 PV. Selectivity is, however, progressively reduced with incremental target PV. A description of five DFPP treatments in three dogs is additionally presented. Semi-selective protein removal was also demonstrated in vivo, with a significantly lower percentage reduction in albumin compared to total globulin (p = 0.01) and fibrinogen (p = 0.007).