Patent ID: 6732573
Filing Date: 2004-05-11
Classification: A61B,G01N

Abstract:
An apparatus for determining the viscosity of the circulating blood of a living being over plural shear rates using a decreasing pressure differential, said apparatus comprising:a lumen being positioned at an angle to a horizontal reference greater than zero degrees, said lumen comprising a first end and a second end, said first end being exposed to atmospheric pressure, said lumen comprising a first known dimension; a flow restrictor having an inlet and an outlet, said outlet being arranged to deliver any blood that passes therethrough to a collector, said flow restrictor including some known dimensions; a valve coupled to the vascular system of the living being at a first port, said valve comprising a second port coupled to said second end and a third port coupled to said inlet; a sensor for detecting the movement of the blood over time through said apparatus, said sensor generating data relating to the movement of the blood over time; a processor, coupled to said valve and said sensor, said processor arranged to operate said valve to create a column of blood in said first lumen and said flow restrictor and to establish a pressure differential between said first end and said outlet, said column of blood moving through said lumen and said flow restrictor at a first shear rate caused by said pressure differential, said movement of said column of blood causing said pressure differential to decrease from said first shear rate for generating said plural shear rates; and wherein said processor calculates the viscosity of the blood based on said data relating to the movement of the column of blood over time, said first known dimension of said lumen and said some known dimensions of said flow restrictor.