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

• Effect of Increased Dialysate Flow Rate on KoA for Urea Between 4 Dialyzers With Different Membrane Packing Densities. [ Time Frame: During the third treatment with each dialyzer (one time during each trial period week) ] [ Designated as safety issue: No ]
  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. [ Time Frame: During the third treatment with each dialyzer (one time during each trial period week) ] [ Designated as safety issue: No ]
• Effect of Increased Dialysate Flow Rate on KoA for Phosphorus Between 4 Dialyzers With Different Membrane Packing Densities. [ Time Frame: During the third treatment with each dialyzer (one time during each trial period week) ] [ Designated as safety issue: No ]
• Effect of Increased Dialysate Flow Rate on Whole Blood Phosphorus Clearance Between 4 Dialyzers With Different Membrane Packing Densities. [ Time Frame: During the third treatment with each dialyzer (one time during each trial period week) ] [ Designated as safety issue: No ]
• Effect of Increased Dialysate Flow Rate on KoA for b2-microglobulin Between 4 Dialyzers With Different Membrane Packing Densities. [ Time Frame: During the third treatment with each dialyzer (one time during each trial period week) ] [ Designated as safety issue: No ]
• Effect of Increased Dialysate Flow Rate on Whole Blood B2-microglobulin Clearance Between 4 Dialyzers With Different Membrane Packing Densities. [ Time Frame: During the third treatment with each dialyzer (one time during each trial period week) ] [ Designated as safety issue: No ]

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.

• Chronic Kidney Disease
• Chronic Renal Disease

• Device: Polyflux HD-C4 Big
  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.
  Other Names:

  • Gambro Polyflux HD-C4 Big dialyzer
  • Gambro Revaclear MAX
• Device: HD-C4 Small
  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.
  Other Names:

  • Gambro Polyflux HD-C4 Small dialyzer
  • Gambro Revaclear dialyzer
• Device: Optiflux 160NR
  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.
  Other Name: Fresenius Optiflux 160NR
• Device: Optiflux 200NR
  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.
  Other Name: Fresenius Optiflux 200NR

• HD-C4 Big
  3 consecutive treatments with the HD-C4 Big dialyzer.
  Intervention: Device: Polyflux HD-C4 Big
• HD-C4 Small
  3 consecutive treatments with the HD-C4 Small dialyzer.
  Intervention: Device: HD-C4 Small
• F160NR
  3 consecutive treatments with the F160NR dialyzer.
  Intervention: Device: Optiflux 160NR
• F200NR
  3 consecutive treatments with the F200NR dialyzer.
  Intervention: Device: Optiflux 200NR

• Bhimani JP, Ouseph R, Ward RA. Effect of increasing dialysate flow rate on diffusive mass transfer of urea, phosphate and beta2-microglobulin during clinical haemodialysis. Nephrol Dial Transplant. 2010 Dec;25(12):3990-5. Epub 2010 Jun 13.
• Leypoldt JK, Cheung AK, Agodoa LY, Daugirdas JT, Greene T, Keshaviah PR. Hemodialyzer mass transfer-area coefficients for urea increase at high dialysate flow rates. The Hemodialysis (HEMO) Study. Kidney Int. 1997 Jun;51(6):2013-7.
• Ouseph R, Ward RA. Increasing dialysate flow rate increases dialyzer urea mass transfer-area coefficients during clinical use. Am J Kidney Dis. 2001 Feb;37(2):316-20.
• Michaels AS. Operating parameters and performance criteria for hemodialyzers and other membrane-separation devices. Trans Am Soc Artif Intern Organs. 1966;12:387-92. No abstract available.
• Leypoldt JK, Cheung AK, Carroll CE, Stannard DC, Pereira BJ, Agodoa LY, Port FK. Effect of dialysis membranes and middle molecule removal on chronic hemodialysis patient survival. Am J Kidney Dis. 1999 Feb;33(2):349-55.
• Leypoldt JK, Cheung AK, Chirananthavat T, Gilson JF, Kamerath CD, Deeter RB. Hollow fiber shape alters solute clearances in high flux hemodialyzers. ASAIO J. 2003 Jan-Feb;49(1):81-7.
• Ward RA, Ouseph R: Modification of membrane characteristics allows a reduction in dialyzer membrane area without loss of performance. J Am Soc Nephrol 18:453A, 2007.
• Chen PS, Toribara TY, Warner H. Microdetermination of phosphorus. Anal Chem 1956; 28: 1756-1758

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