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The ex vivo Isolated Skeletal Microvessel Preparation for Investigation of Vascular Reactivity
Published on: April 28, 2012
Inert gas clearance from tissue by co-currently and counter-currently arranged microvessels
Y Lu1, C C Michel, W Wang
1Institute of Bioengineering, Queen Mary University of London, London, United Kingdom.
Journal of Applied Physiology (Bethesda, Md. : 1985)
|May 19, 2012
Summary
Numerical models show that counter-current capillary flow is less efficient for inert gas clearance from tissues compared to single or co-current flows. This inefficiency increases with higher blood flow rates.
Area of Science:
- Physiology
- Biomedical Engineering
- Gas Transport Dynamics
Background:
- Inert gas clearance from tissues is crucial for understanding physiological processes and diagnosing conditions.
- Existing models for estimating tissue blood perfusion from inert gas clearance may have limitations.
Purpose of the Study:
- To develop and utilize numerical models to elucidate inert gas clearance from tissues.
- To compare the efficiency of gas clearance via single, co-current, and counter-current capillary arrangements.
Main Methods:
- Development of numerical models for gas transport in cylindrical tissue blocks supplied by one or two capillaries.
- Simulation of co-current and counter-current blood flow scenarios.
- Investigation of parameters including blood velocity, gas solubility, and diffusivity.
Main Results:
- Single and co-current capillary arrangements achieve similar inert gas clearance rates under specific flow conditions.
- Both co-current and counter-current flows exhibit linear relationships between clearance rate and perfusion rate.
- Counter-current capillary arrangements demonstrate less efficient inert gas clearance, particularly at higher blood flow rates.
- The simple conduction-capacitance model underestimates clearance rates predicted by numerical models for single and co-current flows.
Conclusions:
- Counter-current flow is less efficient for inert gas tissue clearance than single or co-current flow.
- The findings highlight potential inaccuracies in using simple models for estimating tissue blood perfusion.
- Microvascular architecture significantly influences the interpretation of tissue inert gas clearance data.
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