Theoretical and Experimental Analysis of Hematocrit Distribution in Microcirculatory Networks
Many investigators have reported that capillary hematocrits in a variety of tissues are substantially lower than corresponding systemic hematocrits (Johnson, 1971; Klitzman and Duling, 1979; Lipowsky et al., 1980). Part of this apparent discrepancy is due to the Fahraeus effect in individual segments (Fahraeus, 1928), tube hematocrit (volume fraction of red cells within a vessel) being lower than discharge hematocrit (volume fraction of red cells in blood flowing through a vessel). However, in vitro measurements and theoretical arguments indicate that this effect alone is not sufficient to explain the observed hematocrit reduction.
KeywordsCovariance Eter Hema Timothy
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- Chien S, Usami S, Skalak, R (1984) Blood flow in small tubes. In Renkin EM, Michel CC (eds) Handbook of Physiology, Sec 2, The Cardiovascular System. Vol IV, Pt 1. American Physiological Society, Bethesda, MD, pp 217–249.Google Scholar
- Conte SD, de Boor C (1981) Elementary Numerical Analysis. McGraw-Hill, New York.Google Scholar
- Desjardins C, Duling BR (1987) Microvessel hematocrit: Measurement and implications for capillary oxygen transport. Am J Physiol 252: H494–H503.Google Scholar
- Johnson PC (1971) Red cell separation in the mesenteric capillary network. Am J Physiol 221: 99–104.Google Scholar
- Klitzman B, Duling BR (1979) Microvascular hematocrit and red cell flow in resting and contracting striated muscle. Am J Physiol 237: H481–H490.Google Scholar
- Papenfuss H-D, Gross JF (1986) Mathematical simulation of blood flow in microcirculatory networks. In Popel AS, Johnson PC (eds) Microvascular Networks: Experimental and Theoretical Studies. Karger, Basel.Google Scholar
- Pries AR, Kanzow G, Gaehtgens P (1983) Microphotometric determination of hematocrit in small vessels. Am J Physiol 245: H167–H177.Google Scholar
- Pries AR, Ley K, Gaehtgens P (1986) Generalization of the Fahraeus principle for microvessel networks. Am J Physiol 251: H1324–H1332.Google Scholar
- Pries AR, Ley K, Classen M, Gaehtgens P (submitted for publication) Red cell distribution at microvascular bifurcations. Microvasc Res.Google Scholar