Optimum Albumin Concentration of Supplementation Fluid for Double Filtration Plasmapheresis

Abstract

Until recently, the albumin concentration of supplementation fluid for double filtration plasmapheresis (DFPP) has been empirically determined. Inadequate albumin infusion often leads to hypoproteinemic symptoms such as edema. In the current study, an aimed condensation coefficient (CCaimed) was introduced in an attempt to estimate the appropriate plasma albumin level for each patient. This coefficient is theoretically derived from a one-compartment model for the patient's plasma albumin: CCaimed = CS/CD = 1 - (1 - CR)/[1 - exp(- CC.VR)] where CD and CS are albumin concentrations in discarded plasma and supplementation fluid. CR is the change ratio of albumin concentration in the patient's plasma during a DFPP treatment, and VR(= VS/VP) is the ratio of supplementation fluid volume (VS) to the patient's total plasma volume (VP). And CC denotes the albumin condensation coefficient in a DFPP line, which depends on the filtration fraction of the plasma fractionator (FFPF) and the sieving coefficients of both the plasma separator (SCPS) and the plasma fractionator (SCPF): CC = CD/CP = SCPS.(1 - FFPF.SCPF)/(1 - FFPF) where CP is the albumin concentration of the patient's plasma. From the above relations, CS can be determined as follows: CS = CC.CCaimed.CP Because many kinds of proteins are removed during a single DFPP treatment, a slightly higher albumin concentration in the supplementation fluid is needed to maintain an appropriate plasma level. Therefore, the CR value should be more than unity. For a patient with hematocrit (HCT) of 30%, body weight (BW) of 50 kg, and CP of 3.0 g/dl, who is receiving a DFPP treatment using AP-05H (SCPS of 0.970) and Evaflux 2A (SCPF of 0.526) under FFPF of 0.8 with VS of 500 ml, VP = BW(1- HCT/100)/13 = 50 x (1 - 30/100)/13 = 2.69 L, VR = 500/(2.69 x 1,000) = 0.186, CC = 2.81, and CCaimed = 1.25 assuming 1.1 for CR. Therefore, CS = 2.81 x 1.25 x 3.0 = 10.5 g/dl using the above equations.

The safety measures for double filtration plasma apheresis (DFPP) before ABO-incompatible kidney transplantation

“…We considered this fact could prevent adverse effects, such as hypotension, internal shunt occlusion, fall down, etc., that was supposed to be related with intravascular dehydration due to the decrease of plasma oncotic pressure during DFPP treatment (Table 1). Mineshima et al also reported that inadequate infusion of albumin solution in DFPP treatment might lead to hypoproteinemic symptoms such as edema [11,12]. Like these patients' condition should be the hamper for the safety transplant operation.…”

“…Until now, albumin concentration as supplementation fluid was determined empirically in the each institution [4]. In our country from 7% to 8% albumin solution that was akin to the concentration of serum total protein has been normally used for DFPP treatment.…”

Effects of Operating Conditions on Selectivity of a Plasma Fractionator in Double Filtration Plasmapheresis

“…Mineshima et al (5,6) introduced a theoretical model for albumin transport in the partially discarded DFPP to determine the optimum albumin concentration and optimum amount of the supplementation fluid base. The albumin SC value, however, is constant during the treatment in this model.…”

Theoretical Basis of Pathogenic Substance Removal During Plasmapheresis

“…Actually, DFPP has no stringency for the subclass in removal and there is no limit to the volume that can be processed while the column does not clot; therefore, the conditions in which plasma adsorption is unsuitable can be the target of DFPP. However, DFPP cannot use FFP, which has a lower oncotic pressure than plasma, as a supplementary fluid because DFPP requires supplementary fluids with a higher oncotic pressure—usually an albumin solution with a concentration of about 10% (18). Substances with a low production rate can sometimes be decreased considerably during DFPP, as described above; therefore, patients with active bleeding, those expecting an operation, or those with active infections are appropriately treated using simple plasma exchange with FFP supplementation.…”