Biomaterial Database

[Blood viscosity. Measurement and applications (hyper--and hypoviscosity syndromes) (author's transl)]. 1981

A Larcan, and J F Stoltz, and S Gaillard

Blood has particular rheological properties which partly condition its flow, especially in capillary vessels, and its ability to deliver oxygen. It is not subject to gravitation, pseudoplastic, thixotropic and visco-elastic. Blood viscosity depends upon macroscopic factors, such as erythrocyte aggregation and deformability. Hyperviscosity is observed in cases of increased haematocrit (polycythaemia and relative polycythaemia), increased serum proteins and changes in protein balance (e.g. rise in fibrinogen and immunoglobulins, fall in albumin) as seen in inflammation and dysglobulinaemia, drop in temperature (hypothermia), increased erythrocyte aggregation (shock, fat embolism) or imparied deformability due to various acquired or inherited disorders of red cell membrane or cytoplasma (e.g. sickle cell anaemia, renal failure, hyperlipoproteinaemias, thrombosis, diabetes). The various factors may be combined, as in diabetes. Conversely, hypoviscosity may result from decreased haematocrite, fall in blood proteins and fibrinogen, or hyperthermia. Hyperviscosity can be corrected by acting on its various constituents. Treatments include haemodilution, plasmapheresis, anti-aggregants and drugs improving red cell deformability.

UI	MeSH Term	Description	Entries
D008722	Methods	A series of steps taken in order to conduct research.	Techniques,Methodological Studies,Methodological Study,Procedures,Studies, Methodological,Study, Methodological,Method,Procedure,Technique
D001798	Blood Proteins	Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.	Blood Protein,Plasma Protein,Plasma Proteins,Serum Protein,Serum Proteins,Protein, Blood,Protein, Plasma,Protein, Serum,Proteins, Blood,Proteins, Plasma,Proteins, Serum
D001809	Blood Viscosity	The internal resistance of the BLOOD to shear forces. The in vitro measure of whole blood viscosity is of limited clinical utility because it bears little relationship to the actual viscosity within the circulation, but an increase in the viscosity of circulating blood can contribute to morbidity in patients suffering from disorders such as SICKLE CELL ANEMIA and POLYCYTHEMIA.	Blood Viscosities,Viscosities, Blood,Viscosity, Blood
D004903	Erythrocyte Aggregation	The formation of clumps of RED BLOOD CELLS under low or non-flow conditions, resulting from the attraction forces between the red blood cells. The cells adhere to each other in rouleaux aggregates. Slight mechanical force, such as occurs in the circulation, is enough to disperse these aggregates. Stronger or weaker than normal aggregation may result from a variety of effects in the ERYTHROCYTE MEMBRANE or in BLOOD PLASMA. The degree of aggregation is affected by ERYTHROCYTE DEFORMABILITY, erythrocyte membrane sialylation, masking of negative surface charge by plasma proteins, etc. BLOOD VISCOSITY and the ERYTHROCYTE SEDIMENTATION RATE are affected by the amount of erythrocyte aggregation and are parameters used to measure the aggregation.	Erythrocyte Aggregation, Intravascular,Agglutination, Intravascular,Intravascular Agglutination,Intravascular Erythrocyte Aggregation,Rouleaux Formation, Erythrocyte,Agglutinations, Intravascular,Aggregation, Erythrocyte,Aggregation, Intravascular Erythrocyte,Aggregations, Erythrocyte,Aggregations, Intravascular Erythrocyte,Erythrocyte Aggregations,Erythrocyte Aggregations, Intravascular,Erythrocyte Rouleaux Formation,Erythrocyte Rouleaux Formations,Formation, Erythrocyte Rouleaux,Formations, Erythrocyte Rouleaux,Intravascular Agglutinations,Intravascular Erythrocyte Aggregations,Rouleaux Formations, Erythrocyte
D004912	Erythrocytes	Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.	Blood Cells, Red,Blood Corpuscles, Red,Red Blood Cells,Red Blood Corpuscles,Blood Cell, Red,Blood Corpuscle, Red,Erythrocyte,Red Blood Cell,Red Blood Corpuscle
D006402	Hematologic Diseases	Disorders of the blood and blood forming tissues.	Blood Diseases,Hematological Diseases,Blood Disease,Disease, Blood,Disease, Hematologic,Disease, Hematological,Diseases, Blood,Diseases, Hematologic,Diseases, Hematological,Hematologic Disease,Hematological Disease
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D012212	Rheology	The study of the deformation and flow of matter, usually liquids or fluids, and of the plastic flow of solids. The concept covers consistency, dilatancy, liquefaction, resistance to flow, shearing, thixotrophy, and VISCOSITY.	Flowmetry,Velocimetry,Velocimetries