A nurse is caring for a client who has atrial fibrillation and is receiving warfarin therapy to prevent thromboembolism formation. The nurse should monitor which of the following laboratory values to determine the effectiveness of the medication?

The correct answer is choice A) Activated partial thromboplastin time (aPTT).This is because aPTT is the most commonly used laboratory test to monitor the therapeutic effect of heparin therapy.

Heparin is an anticoagulant that inhibits the formation of thrombin and fibrin, which are essential for blood clotting.Heparin therapy is indicated for the treatment of deep vein thrombosis (DVT), which is a condition where blood clots form in the deep veins of the legs or pelvis.

Choice B) Prothrombin time (PT) is wrong because PT is used to monitor the therapeutic effect of warfarin therapy, not heparin therapy.

Warfarin is another anticoagulant that inhibits the synthesis of vitamin K-dependent clotting factors.Warfarin therapy is also indicated for the treatment of DVT, but it has a different mechanism of action and monitoring than heparin therapy.

Choice C) International normalized ratio (INR) is wrong because INR is a standardized way of reporting PT results that accounts for the variability of different laboratory methods.INR is also used to monitor the therapeutic effect of warfarin therapy, not heparin therapy.

Choice D) Platelet count is wrong because platelet count is not directly affected by heparin therapy.However, platelet count should be monitored periodically in patients receiving heparin therapy to detect heparin-induced thrombocytopenia (HIT), which is a rare but serious complication of heparin therapy that causes a drop in platelet count and an increased risk of thrombosis.

Choice E) Hemoglobin is wrong because hemoglobin is not directly affected by heparin therapy.However, hemoglobin should be monitored periodically in patients receiving heparin therapy to detect bleeding complications, which are the most common adverse effects of heparin therapy.

The normal range for aPTT is 25 to 35 seconds, but the therapeutic range for heparin therapy is usually 1.5 to 2.5 times the normal range, depending on the indication and protocol.

The normal range for PT is 11 to 13 seconds, and the therapeutic range for warfarin therapy is usually an INR of 2 to 3, depending on the indication and protocol

This statement indicates that the patient understands that rivaroxaban (Xarelto) is an anticoagulant that can increase the risk of bleeding and bruising.The patient should avoid activities that may cause injury, such as contact sports, sharp objects, or falls.

Choice A is wrong because aspirin is also an antiplatelet drug that can further increase the risk of bleeding when taken with rivaroxaban.The patient should not take aspirin or any other nonsteroidal anti-inflammatory drugs (NSAIDs) without consulting the prescriber.

Choice C is wrong because rivaroxaban can be taken with or without food.The patient does not need to take the medication with food to prevent stomach upset or absorption problems.

Choice D is wrong because rivaroxaban should be taken as prescribed and not stopped abruptly without consulting the prescriber.Stopping the medication can increase the risk of blood clots and stroke.The patient should not stop taking the medication even if they feel better or have no symptoms.