Calculation of the reflection coefficient from measurements of endogenous vascular indicators.

Title

Calculation of the reflection coefficient from measurements of endogenous vascular indicators.

Creator

Maron M B; Pilati C F

Publisher

Journal of applied physiology (Bethesda, Md. : 1985)

Date

1988
1988-04

Description

The solvent drag reflection coefficient (sigma) for total proteins can be estimated by comparing the relative degrees of concentration of erythrocytes and plasma proteins that occur during fluid filtration in an isolated perfused organ. In this analysis, we evaluated the accuracy of equations proposed by Pilati and Maron [Am. J. Physiol. 247 (Heart Circ. Physiol. 16): H1-H7, 1984] and Wolf et al. [Am. J. Physiol. 253 (Heart Circ. Physiol. 22): H194-H204, 1987] to calculate sigma from these concentration changes. We calculated sigma with each equation using data generated from a mathematical model of fluid and solute flux in membranes with known sigma's. We found that the equation of Wolf et al. provided the closest approximation to the true sigma over the entire range of filtration fractions tested (0.1-0.6), with the differences between the two equations increasing with filtration fraction. At low filtration fractions, the difference in sigma obtained using either approach was found to be inconsequential. At larger filtration fractions, a closer approximation of the true sigma can be obtained using the equation of Wolf et al.

Subject

Animals; Blood Proteins/*analysis; Blood Volume; Capillary Permeability; Filtration; Humans; Mathematics; Methods; Models; Theoretical

Rights

Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).

Pages

1746–1748

Issue

4

Volume

64

Citation

Maron M B; Pilati C F, “Calculation of the reflection coefficient from measurements of endogenous vascular indicators.,” NEOMED Bibliography Database, accessed March 29, 2024, https://neomed.omeka.net/items/show/4639.