Heparin Anti-Xa Assay, Plasma
Method Description Describes how the test is performed and provides a method-specific reference
Residual free factor Xa is measured in plasma by chromogenic substrate assay after addition of bovine antithrombin III (AT III) and factor Xa, which forms an inactive factor Xa-AT III-heparin complex.(Meyers BJ, Plumhoff EA, Gastineau DA, et al: A heparin assay system for measuring unfractionated heparin and low molecular weight heparin using the same standard curve. Blood 1998;92:123b)
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.
Monday through Sunday; Continuously