Question

Describe the changes in clotting and bleeding balance during disseminated intravascular coagulation (DIC).

Describe the most important blood coagulation tests used to monitor the patients receiving heparin and warfarin

Answer 1

DIC(Disseminated Intravascular Coagulation) is a process which is characterized by the clotting which results in the formation of clots in the blood vessels throughout human body.It can lead to Multiple organ failure by generating and depositing fibrin which further leads to microvascular thrombi.The fibrinolytic system is deranged and leads to intravascular clots but if the fibrinolysis gets accelerated it may cause severe bleeding.

It (Thrombosis) can occur in two forms:Acute and Chronic

There is a loss of balance between thrombin's clot forming activity and the plasmin's clot lysing activity.There is initial uncontrolled activation of clotting factors in blood vessels which causes blood clotting throughout the body.It also depletes body's platelets and Coagulation factors which result in increased risk of bleeding.

In this process some Coagulation inhibitors are consumed which if decrease will permit more clot formation.Clotting factors are more consumed in clots development which further leads to more bleeding.So,actually the Coagulation process and fibrinolysis are dysregulated in such a way that they result in widespread clotting with resultant bleeding.

Blood Coagulation tests

INR (International Normalized Ratio)test is used to monitor warfarin dosage and PTT (Partial Thromboplastin Time)test is used for patients receiving Heparin.

The PT and INR tests monitor the effectiveness of warfarin.This drug helps to inhibit the bloodclot formation.The warfarin therapy maintains the balance between preventing clots and causing bleeding in excess.It diagnoses the reason for unexplained bleeding and blood clots.

Heparin acts differently from warfarin.It binds to the antithrombin III which is a natural anticoagulant and then acts on different factors.It does have more effect on intrinsic arm than on extrinsic arm of coagulation,causing a conformational change that activates antithrombin III and its action.