Changing Emphasis in Modern Hemodialysis Therapies: Cost-Effectiveness of Delivering Higher Doses of Dialysis

Abstract

This paper describes the clinical experience of a therapy concept involving advanced functions of a new dialysis machine system (5008 Therapy System, Fresenius Medical Care, Bad Homburg Germany) that is able to provide adequate Kt/V for patients, while consuming lower amounts of dialysate, water and energy during the treatment. The novel “AutoFlow” function of this therapy system adjusts automatically the dialysate flow rate according to the effective blood flow rate of the individual patient without compromising the dose of dialysis the patient receives. The new therapy system of Fresenius Medical Care enables a more widespread application of advanced convective treatment modalities in a more affordable manner. (Int J Artif Organs 2007; 30: 577–82)

A Model to Predict Optimal Dialysate Flow

“…Our results showed that the AutoFlow function has the potential to save osmosis water, the concentration of acid and of bicarbonate, and the energy that is normally required to heat the dialysate, without compromising the dose of dialysis. This finding was postulated also by Kult and Stapf (9). Saving the bicarbonate powder can perform the dialysis session without incident of conductivity and on‐line production, especially when it is extended.…”

Dialysate saving by automated control of flow rates: Comparison between individualized online hemodiafiltration and standard hemodialysis

“…The optimization of dialysate consumption and dialysis dose by the AutoFlow and AutoSub functions has been investigated earlier in a proof‐of‐principle study of eight patients at a single center, in which oHDF with these functions was compared to HD . During HD, the dialysate flow rate was also 500 mL/min, and an AutoFlow factor of 1.2 was also chosen for oHDF.…”

“…The optimization of dialysate consumption and dialysis dose by the AutoFlow and AutoSub functions has been investigated earlier in a proof-of-principle study of eight patients at a single center, in which oHDF with these functions was compared to HD. 20 During HD, the dialysate flow rate was also 500 mL/min, and an AutoFlow factor of 1.2 was also chosen for oHDF. However, all mean flow rates were slightly lower during oHDF in the proofof-principle study than in our study (blood: 314 mL/min vs. 331 mL/min, dialysate: 377 mL/min vs. 398 mL/min, substitution fluid: 67 mL/min vs. 72 mL/min).…”

“…However, high filtration rates (if not appropriately adjusted to the blood flow rates) may result in undesirable hemoconcentration at the dialyzer membrane, and transmembrane pressure alarms of the dialysis monitor. For the maximum filtration fraction (often 25–30% of the blood flow rate), the individual blood parameters hematocrit and total plasma protein must be taken into account; however, in clinical routine, it is not always possible to determine this filtration fraction precisely. At the start of treatment, the treatment parameters blood flow rate and ultrafiltration rate are input parameters for the dialysis monitor.…”

The Removal of Protein-Bound Solutes by Dialysis

“…Indeed, for most patients, target urea removal values can be obtained at reduced monetary cost by using submaximal dialysate flows. 7,8 However, modern dialyzers and dialysis prescriptions, which clear most of the urea from blood passing through the dialyzer, still provide only limited clearances of bound solutes. Only the free portion of such solutes is available for diffusion from the plasma to dialysate, so the gradient driving diffusion is low compared with the total solute concentration (Fig.…”