Which drug would be most appropriate to offer Mrs H as thromboprophylaxis as an inpatient?

• A. Enoxaparin
• B. Warfarin
• C. Rivaroxaban
• D. Heparin

Answer: (D)

The key idea is choosing an inpatient prophylactic anticoagulant that acts quickly, wears off quickly, and can be reversed if needed. Unfractionated heparin fits this well: given for hospital prophylaxis, it provides rapid anticoagulation and, if bleeding occurs or a procedure is needed, its effects can be stopped and reversed quickly (protamine can neutralize it). This makes it particularly useful in acutely ill inpatients where renal function may be a concern or where you anticipate needing to halt anticoagulation on short notice.

Warfarin isn’t suitable for immediate inpatient prophylaxis because it takes several days to reach therapeutic levels and requires INR monitoring, which isn’t practical in a hospital setting for prevention. Rivaroxaban is an oral drug with fixed dosing and limited, less straightforward reversal in the inpatient setting, making it less ideal for hospital prophylaxis. Enoxaparin, while commonly used for inpatient prophylaxis, is renally cleared and can accumulate in kidney impairment, and it has a longer half-life than unfractionated heparin, reducing the ability to rapidly adjust or stop anticoagulation.