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Micro-particle Image Velocimetry for Velocity Profile Measurements of Micro Blood Flows
Published on: April 25, 2013
Viscosity measurements on very small capillary blood samples
M Eugster1, K Häusler, W H Reinhart
1Internal Medicine, Kantonsspital, Chur, Switzerland.
Clinical Hemorheology and Microcirculation
|March 16, 2007
Summary
A new oscillating viscometer accurately measures blood viscosity in tiny capillary blood samples. This device shows potential for clinical use, revealing lower blood viscosity in diabetic patients and higher viscosity in newborns, linked to hematocrit levels.
Area of Science:
- Biomedical Engineering
- Hematology
- Clinical Diagnostics
Background:
- Blood viscosity is a critical parameter with potential clinical significance.
- Measuring viscosity in small capillary blood volumes is challenging but clinically relevant.
- Existing viscometers often require larger sample volumes, limiting bedside applications.
Purpose of the Study:
- To develop and evaluate a novel oscillating viscometer for measuring viscosity in very small blood samples (7 microliters).
- To assess the correlation between hematocrit and blood viscosity using the new device.
- To compare blood viscosity measurements in healthy individuals, diabetic patients, and newborns.
Main Methods:
- Developed a micro-volume oscillating viscometer utilizing a glass capillary and a torsional resonator.
- Evaluated the instrument against a standard viscometer (Contraves LS 30).
- Measured blood viscosity in healthy volunteers with varying hematocrit levels, diabetic patients, and newborns.
Main Results:
- The oscillating viscometer demonstrated strong correlations with hematocrit (r=0.969) and conventional high shear viscosity (r=0.971).
- Diabetic patients showed significantly lower blood viscosity compared to controls, attributed to lower hematocrit.
- Newborns exhibited higher blood viscosity than adults, correlating with their elevated hematocrit levels.
Conclusions:
- The developed oscillating viscometer is suitable for accurate viscosity measurements on very small capillary blood samples.
- The device shows promise for bedside diagnostics, particularly in patient populations like diabetics and neonates.
- Further research is needed to determine the clinical implications of these viscosity findings.
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