Dialysis practice art
dialyzer Membrane performance
Membrane performance, as determined by the effectiveness of solute clearance and biocompatibility, is of greatest concern when choosing a dialyzer. Technological advances in membrane design, chemical composition, and sterilization methods have led to enhanced performance and versatility to the extent that dialyzer choice may reduce morbidity and prolong survival.
High performance membrane (HPM) is a classification used in Japan to identify hollow fiber dialyzers with an advanced level of performance.
The criteria for HPM
- excellent biocompatibility
- effective clearance of target solutes
- pore size larger than conventional hemodialysis (HD) membranes
- HPM should also have a high molecular weight cut-off
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The Japanese Society of Dialysis Therapy (JSDT) also recommends that the pore size in HPM be large enough to allow slight losses of albumin, at a rate of less than 3 g/session with a blood flow rate of 200 ml/min and a dialysate flow rate of 500 ml per min. A larger pore size approximates the glomerular filtration of uremic toxins and albumin in the human kidney, while some protein leakage may enhance albumin turnover.
Some list of high performance membranes
Dialyzer molecular weight
- Each membrane has a molecular weight cut-off for the largest molecule that can pass through it.
- Knowing this parameter allows nephrologists some specificity in the ability to more effectively remove solutes of particular concern in an individual patient.
- Dialyzers have molecular weight cut-offs ranging from 3,000 Da to more than 15,000 Da.
- The new generation of super highflux membranes have cut-offs closer to 65,000 Da.
- Nanotechnology has improved the uniformity of pore size, in contrast to earlier membranes that had a wide range of pore sizes, with fewer large pores produced, and thus limited removal of middle molecular weight uremic toxins.
- Membranes with a homogeneous pore size and a narrow pore size distribution have a sharper cut-off in the sieving coefficient,thus leading to improved passage of low molecular weight proteins while reducing the loss of albumin.