Structural Delineation of the Exeltra Plus 210 Hemodialyzer’s Capillary Pores as Targets to Ameliorate Its Filtration
Assem Hedayat *
College of Dentistry, University of Saskatchewan, 105 Wiggins Road, Saskatoon, SK, Canada S7N 5E4, Canada.
Hamdi Elmoselhi
Saskatchewan Transplant Program, St. Paul’s Hospital, University of Saskatchewan, Saskatoon, SK, Canada S7M 0Z9, Canada.
Ahmed Shoker
Saskatchewan Transplant Program, St. Paul’s Hospital, University of Saskatchewan, Saskatoon, SK, Canada S7M 0Z9, Canada. & Division of Nephrology, Department of Medicine, University of Saskatchewan, 103 Hospital Drive, Saskatoon, SK, Canada S7N 0W8, Canada.
*Author to whom correspondence should be addressed.
Abstract
Aim: To examine potentials to improve solute flux of selected uremic toxins across EXELTRA Plus 210 membrane.
Methodology: Scanning electron microscopy was used to measure the inner and outer fenestrations of the membrane. We selected endothelin, β2-microglobulin, and complement factor D as uremic toxins for this study. The effective diffusivities of these molecules, Deff, were estimated using the equation Deff = Kdiff Do, under different conditions of fenestration densities and capillary diameters, where the hindrance factor, Kdiff, was calculated using the equation Kdiff = (ε / 2 - ε)2.
Results: We estimated the innermost and outermost fenestrations mean pore densities to be 2.71% and 12.06%, respectively. Provided that the fenestrations’ density of the inner walls remained constant, doubling of the capillaries’ diameter and reducing their numbers by half, reduced Kdiff. Applying an electric potential across the outer surface of the capillaries increases the flux of the uremic toxins.
Conclusion: The potential to improve the diffusive transport of uremic toxins through the capillaries’ walls could be enhanced by doubling the inner diameters of the capillaries, increasing the fenestrations density on the inner walls, and applying an electric potential.
Keywords: EXELTRA Plus 210, hemodialysis, capillary, fenestrations, hindrance, effective diffusivity