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Kidney Week

Abstract: PO0927

Clearance of Protein-Bound Uremic Toxins on the Tablo Hemodialysis System

Session Information

Category: Dialysis

  • 701 Dialysis: Hemodialysis and Frequent Dialysis


  • Rivas, Logan, Outset Medical, San Jose, California, United States
  • Hu, Dean, Outset Medical, San Jose, California, United States
  • Aragon, Michael A., Outset Medical, San Jose, California, United States

The Tablo Hemodialysis system (Tablo) is an all in one, easy-to-learn device. While clearance of small and middle molecules has been documented in modern dialysis, the clearance of Protein Bound Uremic Toxins (PBUTs) merits further exploration. Clearance of albumin bound toxins such as indoxyl sulfate (IS) and p-cresol sulfate (PCS) can be limited in dialysis where removal is based on molecular size. Although a clear association has yet to be demonstrated, PBUTs have been considered to be a possible cause of adverse outcomes in patients requiring renal replacement therapy.


A simulated hemodialysis treatment using Tablo was performed with solution of bovine serum albumin and urea. PCS and IS were added to the solution to maintain a constant concentration. A screening design of experiment was performed utilizing the factors of dialysis flow rate (Qd), blood flow rate (Qb), and ultrafiltration (UF). After each factor was changed and allowed to equilibrate, samples were collected from the venous, arterial and spent dialysate lines. Samples of Urea, PCS and IS were analyzed and compared to predicted values from previously published models.


The Tablo system cleared ICS and PCS as predicted or better at all conditions. See table and images for details.


The Tablo system aligned with the PBUT clearance model over the range of system flow settings. Continued investigation into the clinical benefits of PBUT removal is merited to better understand their impact on the overall quality of care for dialysis patients.

Clearance Data
Blood Pump Flow [ml/min]Dialysis Flow Rate [ml/min]Ultra-Filtration Rate [ml/min]Arterial IS Conc. [mg/dL]Spent Dial. IS Conc. [mg/dL]Predicted IS Rate
Actual IS Rate
Arterial PCS Conc. [mg/dL]Spent Dial. PCS Conc.
Predicted PCS Rate
Actual PCS Rate


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