Blood Rheology and Hemodynamics
Oguz K Baskurt1, Herbert J Meiselman2
1Department of Physiology, Akdeniz University Faculty of Medicine, Antalya, Türkiye.
Seminars in Thrombosis and Hemostasis
|December 20, 2023
Summary
Blood viscosity is determined by red blood cell (RBC) properties and aggregation, which are crucial for blood flow. Alterations in these factors can impair tissue perfusion and lead to functional deterioration in various diseases.
Area of Science:
- * Hematology and Hemorheology: Focuses on the physical properties of blood and their clinical implications.
- * Cardiovascular Physiology: Explores blood flow dynamics and tissue perfusion.
Background:
- * Blood is a non-Newtonian fluid whose apparent viscosity depends on shear forces, hematocrit, plasma viscosity, red blood cell (RBC) aggregation, and RBC mechanical properties.
- * RBC deformability is critical for blood flow, especially in microcirculation, and is influenced by membrane properties, cell morphology, and cytoplasmic viscosity.
- * RBC aggregation, a reversible process influenced by shear forces, significantly impacts blood fluidity, particularly in low-flow conditions.
Purpose of the Study:
- * To highlight the most highly cited paper in *Seminars in Thrombosis and Hemostasis* (STH) on blood rheology.
- * To review the determinants of blood viscosity, including hematocrit, plasma viscosity, RBC aggregation, and RBC mechanical properties.
- * To discuss the impact of altered blood rheology in various physiopathological conditions.
Main Methods:
- * Review of fundamental principles of blood rheology and its determinants.
- * Analysis of factors affecting red blood cell (RBC) deformability and aggregation.
- * Examination of the relationship between blood rheology and disease states.
Main Results:
- * Blood viscosity is a complex interplay of cellular and plasma factors, with RBC deformability and aggregation being key determinants.
- * Altered hematocrit, impaired RBC deformability (due to genetic disorders or environmental factors), and increased RBC aggregation (often linked to inflammation) significantly affect blood fluidity.
- * Changes in blood rheology can lead to impaired tissue perfusion and functional deterioration, particularly when vascular properties are also compromised.
Conclusions:
- * Understanding blood rheology, particularly the behavior of red blood cells, is essential for comprehending normal physiology and pathophysiology.
- * Deviations in blood viscosity, driven by factors like altered RBC aggregation and deformability, are implicated in various disease processes.
- * Impaired blood fluidity poses a significant risk to tissue perfusion and organ function.
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