Quantification of the effects of vasomotion on mass transport to tissue from axisymmetric blood vessels
Journal
Journal of Theoretical Biology
Journal Volume
264
Journal Issue
2
Pages
553-559
Date Issued
2010
Author(s)
Abstract
The process known as vasomotion, rhythmic oscillations in vessel diameter, has been proposed to act as a protective mechanism for tissue under conditions of reduced perfusion, since it is frequently only observed experimentally when perfusion levels are reduced. This could be due to a resultant increase in oxygen transport from the vasculature to the surrounding tissue, either directly or indirectly. It is thus potentially of significant clinical interest as a warning signal for ischemia. However, there has been little analysis performed to quantify the effects of vessel wall movement on time-averaged mass transport. We thus present a detailed analysis of such mass transport for an axisymmetric vessel with a periodically oscillating wall, by solving the non-linear mass transport equation, and quantify the differences between the time-averaged mass transport under conditions of no oscillation (i.e. the steady-state) and varying wall oscillation amplitude. The results show that if the vessel wall alone is oscillated, with an invariant wall concentration, the time-averaged mass transport is reduced relative to the steady-state, but if the vessel wall concentration is also oscillated, then mass transport is increased, although this is generally only true when these oscillate in phase with each other. The influence of P?clet number and the non-dimensional rate of consumption of oxygen in tissue, as well as the amplitude of oscillations, are fully characterised. We conclude by considering the likely implications of these results in the context of oxygen transport to tissue. ? 2010 Elsevier Ltd.
Subjects
blood
mass transport
nonlinearity
quantitative analysis
arteriole
article
blood vessel function
blood vessel tone
blood vessel wall
concentration (parameters)
mathematical analysis
nonlinear system
oscillation
oxygen consumption
oxygen transport
priority journal
steady state
transport kinetics
vasomotility
Algorithms
Animals
Biological Transport
Blood Vessels
Capillary Permeability
Elasticity
Humans
Microcirculation
Models, Cardiovascular
Oxygen Consumption
Vasoconstriction
Type
journal article