Structure and hemodynamics of microvascular networks: Heterogeneity and correlations

A. R. Pries, Timothy W Secomb, P. Gaehtgens

Research output: Contribution to journalArticle

105 Citations (Scopus)

Abstract

The objective of this study was to quantify the heterogeneity of topological, morphological, and hemodynamic parameters in microvascular networks and to identify functionally relevant correlations among these parameters. Seven networks in the rat mesentery (383913 vessel segments per network) were examined, and measurements were made of segment generation, diameter, length, and hematocrit in all segments (n = 3,129) and of flow velocity (only in 3 networks, 1,321 segments). In addition, hematocrit, flow rate, and pressure were derived for all segments from a mathematical simulation. All parameters obtained exhibit heterogeneous distributions with coefficients of variation ranging from 0.28 (capillary diameter) to > 1.5 (volume flow and pressure gradient). Several strong correlations exist between parameters, e.g., discharge hematocrit increases with vessel diameter, and shear rate increases with intravascular pressure. Because of such correlations, the extrapolation from average values for 'typical vessels' to network properties can lead to substantial errors. For example, the mean network transit time estimated based on averaged quantities is 6.5 s, which is about 60% higher than the true value (4.08 s). Simplified models of the vascular bed may therefore be inadequate to describe functional properties of the microcirculation.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Volume269
Issue number5 38-5
StatePublished - 1995
Externally publishedYes

Fingerprint

Microvessels
Hematocrit
Hemodynamics
Pressure
Mesentery
Microcirculation
Blood Vessels

Keywords

  • hematocrit
  • pressure
  • shear rate
  • topology
  • volume flow

ASJC Scopus subject areas

  • Physiology

Cite this

Structure and hemodynamics of microvascular networks : Heterogeneity and correlations. / Pries, A. R.; Secomb, Timothy W; Gaehtgens, P.

In: American Journal of Physiology - Heart and Circulatory Physiology, Vol. 269, No. 5 38-5, 1995.

Research output: Contribution to journalArticle

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