The single pass
albumin dialysis (
SPAD) was reported to be an alternative to the Molecular Adsorbent Recirculating System (MARS) for the effective removal of
protein bound substances in
liver failure. Three
SPAD experiments using different
albumin concentrations and
dialysate flow rates were performed. In each experiment, 1000 ml human donor plasma, spiked with 250 mg unconjugated
bilirubin, 200 mg
sulfobromophthalein (BSP) and 115 mg
glycocholic acid (N-[3alpha,7alpha,12alpha-trihydroxy-24-oxycholan-24-yl]
glycine) - a conjugated
bile acid (BA), circulated in a closed loop with 150 ml/min and was dialysed against
albumin solution. These substances are bound to the different binding sites of
albumin and have different association constants. For the comparison, the standard MARS experiment was performed using the same plasma flow rate of 150 ml/min. Moreover, the clearances of
bilirubin for MARS and
SPAD during clinical treatments were calculated using own data and those reported by Seige, Kreymann, Jeschke, et al. in Transplant Proc 1999; 31: 1371-5. The concentrations of
bilirubin, BSP and BA were measured in plasma and
dialysate and for these substances clearances (Cl) were calculated. It is known that the elimination rate of
bilirubin is not very high during
albumin dialysis in comparison to other substances, like
bile acids, due to the high association constant. An increase of
albumin concentration or the flow rate improved the efficacy but also raised the costs substantially. In this study, we have shown that MARS is the more effective kind of
albumin dialysis for the important substances like
bile acids. By
SPAD an improvement of efficacy can be reached only by dramatic increase of the costs. Also, the earlier experiments showed that MARS is safer because of the removal of the stabilizers, which are normally included in the commercial
albumin solutions.