Patent ID: 7901694
Filing Date: 2011-03-08
Classification: G01N,Y10S

Abstract:
1. A method for determining a coagulation parameter for a blood or blood component of a living being, comprising: reacting a sample of blood or a blood component containing fibrinogen with a clotting agent that transforms fibrinogen to fibrin by combining said blood sample with said clotting agent; recording, with recording means for making optical measurements, time and optical density values for the sample that correspond with the optical activity of fibrinogen activity during the reaction with the clotting agent, wherein optical density values plotted at their respective corresponding times over the course of the reaction represent a clotting curve; determining a slope corresponding with the maximum acceleration rate of transformation of fibrinogen to fibrin during the clotting reaction; determining an end of test time (TEOT) corresponding with an optical density value (cEOT) that is indicative of a substantial completion of the reaction of the fibrinogen of the sample and the clotting agent, wherein said time (TEOT) corresponds with the time at which a line of said slope that represents the rate of maximum acceleration of the clotting activity based on the optical activity of the clotting reaction intersects said optical density value (cEOT); determining the optical density value (c determining a time to maximum acceleration (Tmap) of the clotting reaction for the transformation from fibrinogen to fibrin in the sample; recording the optical activity value (c determining an INR value, INRn, for the sample, wherein INRn corresponds with a trapezoidal area defined by the clotting curve and is expressed by the following relationship: INRn=((T