What is the role of heparin in DIC?

• A. It neutralizes thrombin
• B. It increases platelet aggregation
• C. It dissolves clots directly
• D. It replaces clotting factors

Answer: (A)

In DIC, the body’s clotting system is out of control, with widespread thrombin generation leading to microvascular clots and consumption of platelets and clotting factors. Heparin helps by dampening this process. It acts as an anticoagulant by binding to antithrombin III and accelerating its inhibition of thrombin and factor Xa, which reduces further fibrin formation and microthrombi. It doesn’t dissolve clots directly—fibrinolysis is needed for that—and it doesn’t replace clotting factors; those are addressed with supportive transfusions if bleeding is an issue. Heparin is used selectively when thrombosis predominates and bleeding risk is not prohibitive, making its effect on thrombin activity the best answer.