Abstract
A previous communication described the peculiar motion of the plasma trapped between erythrocytes in a capillary (bolus flow). In this paper the effect of this motion on capillary resistance to flow, as well as on dissipative effects associated directly with the cells, are described. The resistance that would be associated with plasma in bolus flow at high Reynolds numbers (relative to a capillary value of 0.01) was studied in a model, in which air bubbles, separated by short segments of water, passed along a glass tube. The resistance to flow, especially with short boluses, was at least ten times greater than that associated with Poiseuille flow. In a second series of experiments at lower Reynolds numbers, a single bolus of liquid was forced by air pressure along a glass tube. In these latter experiments, which more closely simulate biological conditions, the mean resistance to flow was only 30 per cent greater than that associated with Poiseuille flow. In the final series of experiments human blood and plasma, diluted in acid-citrate dextrose (A.C.D.) in varying degrees, were forced through glass micropipettes of capillary dimensions. The mean apparent viscosity of whole blood was found to exceed that of plasma by only about 5 per cent, thus verifying a conjecture to this effect made by Fahraeus and Lindqvist in 1931.
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Selected References
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- BLOCH E. H. Visual changes in the living microvascular system in man and experimental animals as they are related to thrombosis and embolism. Angiology. 1959 Dec;10:421–425. doi: 10.1177/000331975901000604. [DOI] [PubMed] [Google Scholar]
- HAYNES R. H. Physical basis of the dependence of blood viscosity on tube radius. Am J Physiol. 1960 Jun;198:1193–1200. doi: 10.1152/ajplegacy.1960.198.6.1193. [DOI] [PubMed] [Google Scholar]
- PROTHERO J. W., BURTON A. C. The physics of blood flow in capillaries. III. The pressure required to deform erythrocytes in acid-citrate-dextrose. Biophys J. 1962 Mar;2:213–222. doi: 10.1016/s0006-3495(62)86850-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- PROTHERO J., BURTON A. C. The physics of blood flow in capillaries. I. The nature of the motion. Biophys J. 1961 Sep;1:565–579. doi: 10.1016/s0006-3495(61)86909-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- STEHBENS W. E. Turbulence of blood flow. Q J Exp Physiol Cogn Med Sci. 1959 Jan;44(1):110–117. doi: 10.1113/expphysiol.1959.sp001365. [DOI] [PubMed] [Google Scholar]
- WELLS R. E., Jr, MERRILL E. W. Shear rate dependence of the viscosity of whole bllod and plasma. Science. 1961 Mar 17;133(3455):763–764. doi: 10.1126/science.133.3455.763. [DOI] [PubMed] [Google Scholar]