Net ultrafiltration may not eliminate backfiltration during hemodialysis with highly permeable membranes.

Backfiltration of dialysis solution can occur during hemodialysis with highly permeable membranes. A method has recently been developed for determining backfiltration rates in vitro at low dialysate flow rates by measuring changes in the local dialysate concentration of a marker macromolecule via sampling ports added to the hemodialyzer housing. In the present study, the influence of net ultrafiltration on backfiltration rates was determined for five commercial dialyzers containing membranes with different water permeabilities. In vitro experiments were performed (n = 3) using freshly donated whole blood at blood flow rates of 200 and 340 ml/min and at a dialysate flow rate of 100 ml/min. At zero net ultrafiltration, backfiltration rates increased with increasing membrane water permeability and ranged from 0.9 to 6.9 ml/min. At a net ultrafiltration rate of 10 ml/min, backfiltration was eliminated for dialyzers containing membranes with water permeabilities of less than 30 ml/h/mm Hg but remained significant for dialyzers with higher membrane water permeabilities. Therefore, despite a significant net ultrafiltration rate, backfiltration may still occur during hemodialysis with highly permeable membranes.

[1]  N. Man,et al.  Dialysis-associated adverse reactions with high-flux membranes and microbial contamination of liquid bicarbonate concentrate. , 1988, Contributions to nephrology.

[2]  J. Vienken,et al.  Dialysate contamination and back filtration may limit the use of high-flux dialysis membranes. , 1989, ASAIO transactions.

[3]  H. Gurland,et al.  Effect of protein adsorption on diffusive and convective transport through polysulfone membranes. , 1985, Contributions to nephrology.

[4]  E. Ritz,et al.  Water quality--a neglected problem in hemodialysis. , 1987, Nephron.

[5]  C Ronco,et al.  Backfiltration in Clinical Dialysis: Nature of the Phenomenon, Mechanisms and Possible Solutions , 1990, The International journal of artificial organs.

[6]  C. Ronco Backfiltration: A Controversial Issue in Modern Dialysis , 1988, The International journal of artificial organs.

[7]  W. Schoeppe,et al.  Backfiltration in Hemodialyzers with Highly Permeable Membranes , 1984 .

[8]  H. Mann,et al.  Backfiltration in hemodialysis with highly permeable membranes. , 1985, Contributions to nephrology.

[9]  F. Port,et al.  The role of dialysate in the stimulation of interleukin-1 production during clinical hemodialysis. , 1987, American journal of kidney diseases : the official journal of the National Kidney Foundation.

[10]  E. Klein,et al.  Microbial and endotoxin contamination in water and dialysate in the central United States. , 2008, Artificial organs.

[11]  E. Streicher,et al.  The development of a polysulfone membrane. A new perspective in dialysis? , 1985, Contributions to nephrology.

[12]  J. Leypoldt,et al.  Measurement of backfiltration rates during hemodialysis with highly permeable membranes. , 1991, Blood purification.

[13]  E. Streicher,et al.  The Development of a Polysulfone Membrane , 1985 .