Which anticoagulant is administered during a haemodialysis session?

Correct answer: C. Heparin

• A. Clopidogrel is likewise an oral antiplatelet drug and has no role in maintaining circuit patency.
• B. Warfarin is a long-acting oral anticoagulant used for atrial fibrillation and venous thromboembolism. It is not given for the dialysis circuit itself.
• C. CORRECT. HEPARIN is given during dialysis to prevent the blood clotting within the extracorporeal circuit and dialyser. It is administered at the start of the session and its effect is short-lived, with a half-life of only 1–2 hours, which is precisely why the day after dialysis is safe for surgery.
• D. Aspirin is an oral antiplatelet agent, not a circuit anticoagulant.

Note: Heparin acts by potentiating antithrombin III and is monitored by aPTT. Its antidote is protamine sulfate. Contrast with warfarin, which inhibits vitamin K epoxide reductase, is monitored by INR, and is reversed with vitamin K and prothrombin complex concentrate.