Prothrombin Time, Plasma
Method Description Describes how the test is performed and provides a method-specific reference
The STA-R Evolution is a fully automated coagulation instrument, which uses an electromechanical viscosity detection system. The oscillation of a steel ball within the cuvette with the thromboplastin and plasma is monitored by the instrument. At constant viscosity, pendular swings of the ball are obtained within an electromagnetic field. As the plasma clots, the viscosity increases, and the oscillation amplitude of the ball swing decreases. An algorithm uses these variations in oscillation amplitude to determine the clotting time.(RecombiPlasTin 2G Package Insert, 2008; STA-R Evolution Operators Manual)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.