Normal range: 80-120 % of Normal Plasma Activity
Comment: Decreased levels found in congenital anti thrombin III deficiency, liver disease and disseminated intra vascular coagulation (DIC). Patients with values below 0.6 IU/ml are especially at risk of thrombosis. Deficiency can also result in resistance to heparin therapy, necessitating higher doses of the latter. Levels are increased by oral anticoagulants but reduced by heparin. Ideally anticoagulants should be discontinued 14 days prior to sampling
Sample: Citrate plasma, fresh, delivery immediately