Choosing a dialyzer: What clinicians need to know

Abstract

The objectives of hemodialysis have moved from the diffusive clearance of small molecular weight uremic toxins and achieving dialyzer urea adequacy targets to emphasis on improving clinical outcomes in end stage renal failure patients by increasing larger sized uremic toxin clearance. Clinical emphasis in the last few decades has focused on increasing middle molecule weight toxin clearance by hemodiafiltration. Although long‐term data is still lacking, short‐term outcomes appear promising. Advancements in nanotechnology have now introduction a new generation of medium cut‐off membrane dialyzers which allow diffusive clearance of similar middle molecular weight uremia toxin clearance as hemodiafiltration, without increased albumin losses. As these dialyzers have only recently been introduced into clinical practice, no long‐term outcomes are available to determine the relative benefits or advantages of this approach. As dialyzers are now designed to maximize diffusive or convective clearance, or provide a combination, then clinicians can now choose dialyzers tailored to the individual patient needs depending on clinical circumstances. We review the key important features in choosing a dialyzer for patients with end stage renal failure and acute kidney injury.

Slipping Through the Pores: Hypoalbuminemia and Albumin Loss During Hemodialysis

“… 34 Current membranes offer similar levels of biocompatibility and represent an improvement over early, regenerated cellulose (ie, Cuprophan ® ) membranes. 46 In addition to protein losses into dialysate (discussed below), protein adsorption to the membrane and tubing can occur. 1 , 29 , 47 …”

“…The ideal dialyzer facilitates removal of toxins from the blood while avoiding loss of physiologically beneficial molecules. 46 Until such a dialyzer is developed, the selection of dialyzers should suit the needs of a given patient, with additional consideration to the HD facility and to cost. 46 , 50 As will be discussed in greater detail, most membranes used for conventional HD can be broadly categorized as low flux or high flux.…”

The effect of thyme honey on anemia in hemodialysis patients

“…In the hemodialysis technique, many valuable and useful nutrients in the blood and many vitamins, especially water-soluble ones such as vitamin C, small molecules, and proteins that are unable to bind to proteins, are lost when performing exchanges between soluble substances in the patient's blood and hemodialysis fluid through the semipermeable membrane of the filters (28). When using high-flux membranes, depending on the type of filter, molecules with molecular weights between 10 and 50 kDa are also capable of passing through the membrane pores of these types of filters (29), so most compounds present in thyme honey that are capable of dissolving in water and having much lower molecular weight are easily wasted during hemodialysis.…”

The Dialyzer Identification Code (DIC): A filter characteristics codification for dialyzer choice in renal replacement therapy

“…A wider range of solute molecular weight (MW) removal has been obtained by both convective and diffusive modalities, a combination of them and the adsorption due to optimization of the multidimensional characteristics of membrane 6 . The filter choice resulting from the patient’s needs, based on such features, has been well described by Haroon and Davenport 7 . Today, in the clinical practice, the challenge is to find the best filter characteristics for a quick and easy assessment for the individual patient’s needs.…”