Comparative Effects Of Dialysate Flow Rate And Membrane Packing On The Performance Of Dialyzers Used For Hemodialysis

Comparative Effects Of Dialysate Flow Rate And Membrane Packing On The Performance Of Dialyzers Used For Hemodialysis

Effect Of Dialysate Flow Rate On Mass Transfer Coefficient - Area (KoA) In Dialyzers With Different Membrane Packing Densities

The purposes of this study are to determine if the performance of a dialyzer depends on how tightly the hollow fiber membranes are packed in the housing of the dialyzer (the membrane packing density) and if that dependence is a function of the dialysate flow rate. The study will examine how efficiently three different sized molecules pass through a dialyzer membrane at different dialysate flow rates in dialyzers with different membrane packing densities. Transfer of urea, phosphorus and beta-2-microglobulin from blood to dialysate will be measured during clinical hemodialysis using four different dialyzers, each used at three different dialysate flow rates. The data derived from these measurements may provide insight into the importance of membrane packing density as a design parameter for hemodialyzers and if changing the membrane packing density might provide equivalent performance at a lower dialysate flow rate.

Three consecutive treatments with the HD-C4 Big. During the third treatment, dialyzer clearances of urea, phosphorus and β2-microglobulin will be determined at a blood flow rate of 400 mL/min and dialysate flow rates of 350 mL/min, 500 mL/min and 800 mL/min.

Three consecutive treatments with the HD-C4 Small. During the third treatment dialyzer clearances of urea, phosphorus and β2-microglobulin will be determined at a blood flow rate of 400 mL/min and dialysate flow rates of 350 mL/min, 500 mL/min and 800 mL/min.

Three consecutive treatments with the HD-C4 Small. During the third treatment dialyzer clearances of urea, phosphorus and β2-microglobulin will be determined at a blood flow rate of 400 mL/min and dialysate flow rates of 350 mL/min, 500 mL/min and 800 mL/min.

Three consecutive treatments with the HD-C4 Small. During the third treatment dialyzer clearances of urea, phosphorus and β2-microglobulin will be determined at a blood flow rate of 400 mL/min and dialysate flow rates of 350 mL/min, 500 mL/min and 800 mL/min.

Effect of Increased Dialysate Flow Rate on KoA for Urea Between 4 Dialyzers With Different Membrane Packing Densities.

KoA is a constant that describes the efficiency of a dialyzer in removing urea. KoA is determined by surface area of the membrane, the thickness of the membrane and pore size.

Effect of Increased Dialysate Flow Rate on Whole Blood Urea Clearance Between 4 Dialyzers With Different Membrane Packing Densities.

Effect of Increased Dialysate Flow Rate on KoA for Phosphorus Between 4 Dialyzers With Different Membrane Packing Densities.

Effect of Increased Dialysate Flow Rate on Whole Blood Phosphorus Clearance Between 4 Dialyzers With Different Membrane Packing Densities.

Effect of Increased Dialysate Flow Rate on KoA for b2-microglobulin Between 4 Dialyzers With Different Membrane Packing Densities.

Effect of Increased Dialysate Flow Rate on Whole Blood B2-microglobulin Clearance Between 4 Dialyzers With Different Membrane Packing Densities.

Inclusion Criteria: Stable hemodialysis patients dialyzing through a native fistula or Gore-Tex graft. The access must be capable of delivering a stable blood flow of 400 ml/min. Age older than 18 years. Fluid removal requirement less than 3 liters per treatment. Exclusion Criteria: Noncompliance with dialysis regimen. Hematocrit less than 28%. Active infection

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