NUR 209 Exam 3 Med Surg II 2026/2027
Study Questions with Verified Answers
and Comprehensive Rationales Grade A
1. What is the antidote for Warfarin?
Correct Answer: Phytonadione - Vitamin K, Aquamephyton
Rationale:
1. Warfarin is a vitamin K antagonist that inhibits clotting factor synthesis (II,
VII, IX, X).
2. Vitamin K (phytonadione) reverses warfarin's effects by providing the
substrate for clotting factor production.
3. Aquamephyton is a brand name for injectable vitamin K.
4. For life-threatening bleeding, fresh frozen plasma (FFP) or prothrombin
complex concentrate (PCC) may also be needed for rapid reversal.
2. What are examples of anticoagulants? (8)
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Correct Answer: Heparin, Enoxaparin (Lovenox), Warfarin (Coumadin),
Dalteparin (Fragmin), Dabigatran (Pradaxa), Argatroban, Fondaparinux
(Arixtra), Rivaroxaban (Xarelto)
Rationale:
1. Heparin and low molecular weight heparins (enoxaparin, dalteparin) are
parenteral anticoagulants.
2. Warfarin is an oral vitamin K antagonist.
3. Direct thrombin inhibitors: dabigatran (oral), argatroban (IV).
4. Factor Xa inhibitors: rivaroxaban (oral), fondaparinux (subcutaneous).
3. What are normal platelet levels?
Correct Answer: 150,000-400,000 (150k-400k)
Rationale:
1. Normal platelet count is 150,000 to 400,000 per microliter.
2. Thrombocytopenia (<150,000) increases bleeding risk.
3. Thrombocytosis (>400,000) increases clotting risk.
4. What is the normal PT level in a patient not on anticoagulants?
Correct Answer: 11-12.5 seconds
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Rationale:
1. Prothrombin time (PT) measures the extrinsic and common coagulation
pathways.
2. Normal PT is 11-12.5 seconds for a healthy adult not taking blood thinners.
3. PT is prolonged by warfarin (monitors warfarin therapy).
5. What is the normal INR level in a patient not taking anticoagulants?
Correct Answer: 1
Rationale:
1. International Normalized Ratio (INR) standardizes PT results across different
laboratories.
2. Normal INR is approximately 1.0 (range 0.8-1.2).
3. Therapeutic INR for warfarin is typically 2.0-3.0 (mechanical heart valves:
2.5-3.5).
6. What is the normal aPTT lab value?
Correct Answer: 30-40 seconds
Rationale:
1. Activated Partial Thromboplastin Time (aPTT) measures the intrinsic and
common coagulation pathways.