Biomaterial Database

Flow through venous cannulae. 1977

A Selwyn, and W J Russell

Fluid flow through modern cannulae is not simple and cannot be expressed in classical terms. Progressively increasing the length of a cannula diminishes flow predictably but altering the bore of the cannula does not give a fourth power improvement in flow but rather a linear one. A reasonable working value for the relative viscosity of ACD blood in infusions would seem to be 2-6 below about 125 ml/minute flow (saline). The decline in relative viscosity above this may be caused by turbulence in the saline flow.

UI	MeSH Term	Description	Entries
D001783	Blood Flow Velocity	A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.	Blood Flow Velocities,Flow Velocities, Blood,Flow Velocity, Blood,Velocities, Blood Flow,Velocity, Blood Flow
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
D002404	Catheterization	Use or insertion of a tubular device into a duct, blood vessel, hollow organ, or body cavity for injecting or withdrawing fluids for diagnostic or therapeutic purposes. It differs from INTUBATION in that the tube here is used to restore or maintain patency in obstructions.	Cannulation,Cannulations,Catheterizations
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
D012462	Saline Solution, Hypertonic	Hypertonic sodium chloride solution. A solution having an osmotic pressure greater than that of physiologic salt solution (0.9 g NaCl in 100 ml purified water).	Hypertonic Saline Solution,Hypertonic Solution, Saline,Sodium Chloride Solution, Hypertonic,Hypertonic Saline Solutions,Hypertonic Solutions, Saline,Saline Solutions, Hypertonic,Sodium Chloride Solutions, Hypertonic,Saline Hypertonic Solution,Saline Hypertonic Solutions,Solution, Hypertonic Saline,Solution, Saline Hypertonic,Solutions, Hypertonic Saline,Solutions, Saline Hypertonic
D012996	Solutions	The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)	Solution
D014783	Viscosity	The resistance that a gaseous or liquid system offers to flow when it is subjected to shear stress. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Viscosities