Influence of vessel diameter on red cell distribution at microvascular bifurcations

R T Carr1, L L Wickham

  • 1Department of Chemical Engineering, University of New Hampshire, Durham 03824-3591.

The uneven distribution of red blood cells (RBCs) to daughter branches at microvascular bifurcations, often referred to as "plasma skimming," has been characterized in previous studies by comparisons of flux-flow plots of red cell flow fraction (F*) versus volumetric flow fraction (Q*) at single junctions. Comparisons of flux-flow plots for single bifurcations with differing daughter/parent vessel diameter ratios (Dd/Dp = 1.0 vs 0.5) have been made to reveal the influence of vessel size on red cell distribution at vessel junctions of four different geometries (100 x 100, 50 x 50, 100 x 50, 50 x 25 microns). Experimental data determined by effluent collection were compared to those from video fluorescence microscopy experiments, as well as to numerical computations from theoretical models. Statistical comparisons using a likelihood ratio test indicate that vessel diameter ratio, Dd/Dp, has no detectable influence on RBC distribution in these microvascular bifurcations.

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