Search results
Results from the WOW.Com Content Network
The partial thromboplastin time (PTT), also known as the activated partial thromboplastin time (aPTT or APTT), is a blood test that characterizes coagulation of the blood. A historical name for this measure is the Kaolin-cephalin clotting time ( KCCT ), [ 1 ] reflecting kaolin and cephalin as materials historically used in the test.
Activated clotting time (ACT), also known as activated coagulation time, is a test of coagulation. [1] [2]The ACT test can be used to monitor anticoagulation effects, such as from high-dose heparin before, during, and shortly after procedures that require intense anticoagulant administration, such as cardiac bypass, interventional cardiology, thrombolysis, extra-corporeal membrane oxygenation ...
Native heparin is a polymer with a molecular weight ranging from 3 to 30 kDa, although the average molecular weight of most commercial heparin preparations is in the range of 12 to 15 kDa. [60] Heparin is a member of the glycosaminoglycan family of carbohydrates (which includes the closely related molecule heparan sulfate ) and consists of a ...
Fresh normal plasma has all the blood coagulation factors with normal levels. If the problem is a simple factor deficiency, mixing the patient plasma 1:1 with plasma that contains 100% of the normal factor level results in a level ≥50% in the mixture (say the patient has an activity of 0%; the average of 100% + 0% = 50%). [3]
The effects of LMWHs cannot be acceptably measured using the partial thromboplastin time (PTT) or activated clotting time (ACT) tests. [16] Instead, LMWH therapy is monitored by the anti-factor Xa assay, measuring anti-factor Xa activity rather than a clotting time. The methodology of an anti-factor Xa assay is that patient plasma is added to a ...
Internationalized normalized ratio (INR) is also a warfarin study, with therapeutic ranges of 2–3 for standard warfarin and 3–4.5 for high-dose warfarin. [6] In a veterinary study of bovine animals, the mean ACT was 145 seconds with a range of 120–180 seconds. Standard deviations were 18 and 13 for the first and second sampling, respectively.
The reference range for prothrombin time depends on the analytical method used, but is usually around 12–13 seconds (results should always be interpreted using the reference range from the laboratory that performed the test), and the INR in absence of anticoagulation therapy is 0.8–1.2. The target range for INR in anticoagulant use (e.g ...
Thrombin time can be prolonged by heparin, fibrin degradation products, and fibrinogen deficiency or abnormality. Thrombin time is not affected by anti-Xa anticoagulants such as rivaroxaban or apixaban , but is very sensitive to direct thrombin inhibitors including dabigatran , argatroban , and bivalirudin .