The aPTT is the most common procedure used to monitor the unfractionated heparin therapy. Which of the reagents used in the test provides the activation of the formation of the fibrin clot?
A) Thromboplastin/calcium mixture
B) Activated partial thromboplastin and calcium
C) Thrombin and fibrinogen
D) Normal pooled plasma and thrombin

Question

Quizplus · Accepted Answer

The aPTT test measures the time it takes for a clot to form in plasma after adding an activator and calcium. The reagent used in the test is usually a partial thromboplastin combined with calcium. This reagent activates the intrinsic coagulation pathway, leading to the formation of a fibrin clot. Choice A is incorrect as thromboplastin is not used in the aPTT test. Choice C is incorrect as it mentions thrombin and fibrinogen, which are part of the extrinsic pathway and not used in the aPTT test. Choice D is also incorrect as it mentions normal pooled plasma and thrombin, which is used in the prothrombin time (PT) test and not the aPTT test.

The APTT Is the Most Common Procedure Used to Monitor