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Updated: May 26, 2026
11:26
Assessing Cerebral Autoregulation via Oscillatory Lower Body Negative Pressure and Projection Pursuit Regression
Published on: December 10, 2014
Nonlinear cardiovascular regulation consequent to changes in blood viscosity
Beatriz Y Salazar Vázquez1, Pedro Cabrales, Amy G Tsai
1Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093 0412, USA.
Clinical Hemorheology and Microcirculation
|January 5, 2012
Summary
Moderate increases in blood viscosity can improve cardiovascular function by enhancing nitric oxide production and microvascular flow. This finding supports new treatments for hemorrhage, potentially reducing reliance on blood transfusions.
Area of Science:
- Cardiovascular Physiology
- Hemodynamics
- Vascular Biology
Background:
- Elevated blood viscosity is often linked to cardiovascular disease.
- Previous research focused on extreme viscosity changes, potentially skewing understanding.
- Hemoconcentration studies suggested negative impacts of increased blood viscosity.
Purpose of the Study:
- To investigate the effects of moderate increases in hematocrit (Hct) and plasma viscosity on cardiovascular function.
- To explore the underlying mechanisms of viscosity-related vascular regulation.
- To inform the development of novel treatments for hemorrhage.
Main Methods:
- Analysis of existing epidemiological data in humans.
- Experimental studies examining blood and plasma viscosity effects.
- Investigation of nitric oxide production and shear stress responses.
- Assessment of microvascular function and perfusion.
Main Results:
- Moderate increases in Hct were found to improve cardiovascular function.
- Increased blood viscosity stimulates nitric oxide production, reducing vascular resistance.
- Enhanced microvascular function and perfusion were observed with increased viscosity.
- Similar benefits were seen with increased plasma viscosity in hemodiluted states.
Conclusions:
- Nonlinear regulation of vascular resistance by blood viscosity improves cardiovascular and microvascular function.
- Findings challenge the traditional view of blood viscosity as solely detrimental.
- Viscogenic plasma expanders offer a potential alternative to blood transfusions for hemorrhage management.
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