A nurse is caring for a client who has hypertension and asks the nurse about a prescription for propranolol. The nurse should inform the client that this medication is contraindicated in clients who have a history of which of the following conditions?

Choice A reason: Warfarin PO is not a suitable medication for DVT prophylaxis in the immediate postoperative period, as it has a slow onset of action and requires frequent monitoring of the INR (international normalized ratio). Warfarin may be used for long-term anticoagulation, but it is not effective for preventing the formation of new clots.

Choice B reason: Enoxaparin subcutaneous is a suitable medication for DVT prophylaxis in the immediate postoperative period, as it has a rapid onset of action and does not require frequent monitoring of the coagulation status. Enoxaparin is a low-molecular-weight heparin that inhibits the formation of thrombin and prevents the growth of existing clots.

Choice C reason: Aspirin PO is not a suitable medication for DVT prophylaxis in the immediate postoperative period, as it has a weak anticoagulant effect and may increase the risk of bleeding. Aspirin is an antiplatelet agent that inhibits the aggregation of platelets and prevents the formation of arterial clots, but it is not effective for preventing venous clots.

Choice D reason: Heparin infusion is not a suitable medication for DVT prophylaxis in the immediate postoperative period, as it requires continuous intravenous administration and frequent monitoring of the aPTT (activated partial thromboplastin time). Heparin is an unfractionated heparin that inhibits the formation of thrombin and prevents the growth of existing clots, but it has a narrow therapeutic window and a high risk of bleeding.

Choice A reason: This is incorrect because aspirin is not a suitable medication for preventing venous thromboembolism (VTE) in a client who is postoperative following hip arthroplasty. Aspirin is a nonsteroidal anti-inflammatory drug (NSAID) that has antiplatelet and analgesic effects, but it is not as effective as anticoagulants for VTE prophylaxis.

Choice B reason: This is incorrect because alteplase is not a medication for preventing VTE, but for treating it. Alteplase is a thrombolytic agent that dissolves existing blood clots by activating plasminogen. It is used for acute ischemic stroke, myocardial infarction, and massive pulmonary embolism, but it has a high risk of bleeding and is contraindicated in clients who have had recent surgery.

Choice C reason: This is incorrect because clopidogrel is not a medication for preventing VTE, but for preventing arterial thrombosis. Clopidogrel is an antiplatelet agent that inhibits the adenosine diphosphate (ADP) receptor on platelets, preventing their aggregation. It is used for clients who have had acute coronary syndrome, percutaneous coronary intervention, or ischemic stroke, but it is not effective for VTE prophylaxis.

Choice D reason: This is correct because enoxaparin is a medication for preventing VTE in a client who is postoperative following hip arthroplasty. Enoxaparin is a low molecular weight heparin (LMWH) that inhibits factor Xa and thrombin, preventing the formation of fibrin. It is administered subcutaneously once or twice daily and does not require routine laboratory monitoring. It has a lower risk of bleeding and heparin-induced thrombocytopenia (HIT) than unfractionated heparin.