ISSN:
1741-0444
Keywords:
Blood flow
;
Diffusion
;
Dispersion
;
Indicator dilution
;
Radioactive clearance
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Abstract The dispersion of I 131 and I 131 -HSA in plasma and whole pig's blood has been studied by observing the clearance of a well mixed bolus, containing the radioactive labelled solute, at a point downstream, during flow through flexible straight and curved tubes. The dispersion of I 131 -HSA in plasma flow through a straight tube is consistent with a mechanism of diffusion superimposed on a parabolic velocity profile. In curved tubes, secondary flows produce additional dispersion of I 131 -HSA in plasma. With whole blood additional dispersion of I 131 -HSA occurs in straight tubes owing to the tumbling and rolling of red blood cells near the vessel wall. The onset of secondary flows and increased dispersion in curved tubes requires a relatively high flow rate with whole blood owing to its increased viscosity at low shear rates. At high flow rates, above a velocity of 10 cm s−1, a phase separation of cells and plasma occurs, with the formation of a relatively stagnant cell-free plasma layer on the inner wall of the bend.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02441524
Permalink
