Question 1

The antiplatelet agent abciximab is structurally related to&#10;A) calcium channel blockers.&#10;B) a bacterial enzyme.&#10;C) the ADP receptor.&#10;D) a vaccine.

Accepted Answer

a vaccine.

Question 2

To reverse anticoagulation caused by heparin,________ is usually administered.&#10;A) prostaglandin&#10;B) warfarin&#10;C) tranexamic acid&#10;D) protamine

Accepted Answer

Protamine is the direct reversal agent for heparin. It works by binding to heparin and forming a complex that is then cleared from the body by the kidneys.

Question 3

When using aspirin as an antiplatelet agent,how many days before any planned surgery or dental procedures should it be stopped?&#10;A) 2 days&#10;B) 7 days&#10;C) 14 days&#10;D) 21 days

Accepted Answer

Aspirin has an antiplatelet effect that lasts for the lifespan of the platelet (7-10 days). Therefore, it is generally recommended to stop aspirin 7 days before any planned surgery or dental procedures to reduce the risk of bleeding.

Question 4

When a tissue is injured,the process of clotting begins.Which statement is true about that process?&#10;A)Thrombin forms prothrombin.&#10;B)The process is dependent on intrinsic and extrinsic pathways.&#10;C)Potassium ions play a crucial role in clotting.&#10;D)Fibrin forms fibrinogen.

Accepted Answer

The process of clotting is dependent on both intrinsic and extrinsic pathways. Intrinsic pathway is activated within the injured blood vessel while the extrinsic pathway is activated by the release of tissue factor from the injured tissue. Both pathways ultimately lead to the formation of fibrin clot.

Note: None of the other options are true. Thrombin actually forms fibrin from fibrinogen, potassium ions do not play a crucial role in clotting, and fibrinogen does not form fibrin.

Question 5

Which one of the following is an endogenous substance known to inhibit coagulation?&#10;A) cAMP&#10;B) Thromboxane A?&#10;C) ADP&#10;D) von Willebrand factor

Accepted Answer

cAMP is an endogenous substance known to inhibit coagulation by activating protein kinase A, which in turn inhibits platelet activation and aggregation. Thromboxane A₂, ADP, and von Willebrand factor, on the other hand, are procoagulant substances that promote platelet activation and aggregation.

Question 6

The benefits of enoxaparin over heparin include that it:&#10;A) is less likely to cause thrombocytopaenia and is more effective in reducing mortality and myocardial infarction in unstable angina.&#10;B) has a longer half-life requiring less frequent monitoring and is safer in pregnancy.&#10;C) A and B.&#10;D) neither A nor B.

Accepted Answer

Enoxaparin has been shown to be less likely to cause thrombocytopenia and is more effective in reducing mortality and myocardial infarction in unstable angina compared to heparin. Additionally, enoxaparin has a longer half-life, requiring less frequent monitoring, and is safer in pregnancy.

Question 7

After about ________ hours of oral anticoagulant therapy with warfarin,the heparin can be withdrawn,as it takes this amount of time for the oral anticoagulant to exert its effect.&#10;A) 2&#10;B) 12&#10;C) 24&#10;D) 48

Accepted Answer

Warfarin's anticoagulant effect typically takes about 48 hours to become established. This delay is due to the time required for the depletion of functional vitamin K-dependent clotting factors.

Question 8

What is the haemostatic agent used in colposcopy procedures?&#10;A)Monsel's solution&#10;B)Calcium alginate&#10;C)Eltrombopag&#10;D)Octocog alfa

Accepted Answer

Monsel's solution is a topical haemostatic agent commonly used in colposcopy procedures to control bleeding. Calcium alginate is used in wound dressings and does not have haemostatic properties. Eltrombopag and Octocog alfa are medications used in the treatment of thrombocytopenia and hemophilia, respectively.

Question 9

The benefit of ________ for the treatment of thrombosis is that it is clot-specific,thereby reducing the risk of generalised haemorrhage.&#10;A) warfarin&#10;B) urokinase&#10;C) streptokinase&#10;D) tissue plasminogen activator

Accepted Answer

Tissue plasminogen activator (tPA) has the benefit of being clot-specific, meaning it only targets the clot and not other parts of the body that may not need to be dissolved. This reduces the risk of generalised haemorrhage, which is a potential complication with other thrombolytic agents such as urokinase and streptokinase. Warfarin, on the other hand, is an anticoagulant and not a thrombolytic agent, and its benefit is mainly in preventing the formation of new clots rather than dissolving existing ones.

Deck 47: Antithrombotic, Fibrinolytic and Haemostatic Agents