CEA Nursing Practice Exam

What is the primary mechanism of action for dabigatran etexilate (Pradaxa) as an anticoagulant?

1. Prothrombin inhibition

2. Thrombin inhibition

3. Plasminogen inhibition

4. Factor X inhibition

The correct answer is: Thrombin inhibition

Dabigatran etexilate (Pradaxa) functions primarily as a direct thrombin inhibitor. This means it specifically targets and inhibits thrombin (factor IIa), which is a crucial enzyme in the coagulation cascade that facilitates the conversion of fibrinogen to fibrin, ultimately leading to clot formation. By binding to thrombin, dabigatran prevents the formation of fibrin clots, effectively reducing the risk of thromboembolic events such as stroke in patients with atrial fibrillation or those undergoing certain types of surgery. Understanding the mechanism of action is essential in distinguishing dabigatran from other anticoagulants. For example, prothrombin inhibition refers to the interference with the conversion of prothrombin to thrombin, but dabigatran does not act by inhibiting prothrombin itself. Similarly, plasminogen inhibition relates to the breakdown of fibrin clots and not the formation of clots, which is outside the primary action of dabigatran. As for factor X, this component is a key player in the coagulation pathway, but dabigatran does not inhibit it; instead, factor Xa inhibitors are designed specifically for that purpose. Thus, the correct