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Abstract: SA-PO557

Can Oral Phosphate Binders Be Added to Dialysate to Improve the Efficacy of Hemodialysis?

Session Information

Category: Dialysis

  • 801 Dialysis: Hemodialysis and Frequent Dialysis


  • Tehrani, Rouzbeh, Temple University, Philadelphia, Pennsylvania, United States
  • Gillespie, Avrum, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania, United States
  • Alderfer, Juliana, Temple University, Philadelphia, Pennsylvania, United States

Can commercially available polymeric phosphate binders, Sevelamer carbonate (SC), be added to the dialysate to improve diffuse clearance and reduce dialysate usage while decreasing blood-dialysate phosphate gradients? Sevelamer carbonate is an orally administered, non-absorbed phosphate-binding anion exchange resin. It is a buffered form of Sevelamer hydrochloride.


This is an in-vitro hemodialysis experiment using 1 liter of freshly collected Li-heparinized porcine blood with an average blood flow rate of 30 mL/min and dialysate flow of 50 mL/min, two peristaltic pumps, Fresenius Optiflux hemodialysis membranes, and CitraPure dialysate concentrate (Rockwell Medical) which was diluted and the pH adjusted using sodium bicarbonate (Solcart B, B.Braun). For the phosphate experiment, 3 tablets of SC were crushed and added to the dialysate, 2700 mg of active-SC/L. SC leaching to blood was tested by (i) examining blood specimens after prolonged 5-hour hemodialysis, (ii) using highly concentrated SC-added dialysate (5 to 10 g/L) and increased transmembrane pressure, and measuring the reverse filtrate for SC particles.


For the hyperphosphatemia experiment, the start serum phosphorus was 8 mg/dL. After 30 minutes of dialysis, the phosphorus was 5.5 mg/dL. SC was added and the phosphate dropped to 2.5 mg/dL at 100 minutes. SC was then added again and phosphate dropped to 2 mg/dL. No suspended particles were detected passing through the membrane from dialysate to blood.


The addition of Sevelamer Carbonate (SC) effectively lowered phosphate using recirculated dialysate and can be incorporated into a novel hemodialysis machine that can recirculate dialysate, reducing water consumption for both in-center and home hemodialysis. While SC effectively reduced phosphate levels, its addition to the dialysate has been found to influence the dialysate pH. Therefore, careful consideration must be given to pH adjustment when utilizing SC. Maintaining appropriate dialysate pH is crucial for ensuring patient safety and optimizing dialysis outcomes.