A nurse is preparing to administer alteplase, a thrombolytic drug, to a client who has an acute myocardial infarction. The nurse knows that this drug works by which mechanism?

Alteplase works by activating plasminogen, which converts to plasmin, an enzyme that degrades fibrin.Fibrin is a protein that forms the meshwork of a blood clot, so by breaking it down, alteplase helps dissolve the clot and restore blood flow.

Choice A is wrong because alteplase does not inhibit platelet aggregation and adhesion.

Platelets are blood cells that stick together and form the initial plug in a blood clot.Alteplase does not affect platelets directly, but rather targets fibrin.

Choice B is wrong because alteplase does not interfere with the coagulation cascade.

The coagulation cascade is a series of reactions that lead to the formation of fibrin from fibrinogen.Alteplase does not inhibit any of the steps in this process, but rather activates plasminogen, which is already present in the blood.

Choice D is wrong because alteplase does not block the action of platelet activators or receptors.

Platelet activators are substances that stimulate platelets to aggregate and adhere, such as thrombin, ADP, and collagen.

Platelet receptors are molecules on the surface of platelets that bind to these activators or to other platelets, such as GPIIb/IIIa and GPVI.Alteplase does not affect these molecules, but rather targets fibrin.

Subcutaneous injection in the abdomen.This is because enoxaparin is a low-molecular-weight heparin that is administered subcutaneously, usually in the abdomen or outer thigh.The drug should be clear and colorless or pale yellow.The dosage for adults is typically 30mg every 12 hours for 7 to 10 days, or 40mg once a day for 3 weeks after hip replacement surgery.The needle should be inserted fully into the skin and the syringe plunger should be pressed down to inject the drug.Injection sites should be rotated and areas of active skin disease or injury should be avoided.

Choice A is wrong because intramuscular injection in the deltoid muscle is not the recommended route or site for enoxaparin.Intramuscular injection may cause bleeding, bruising, or hematoma formation.

Choice C is wrong because intravenous infusion in a peripheral vein is not the recommended route for enoxaparin.Enoxaparin can be given intravenously only as a bolus injection for acute coronary syndrome, not as an infusion.

Choice D is wrong because intradermal injection in the forearm is not the recommended route or site for enoxaparin.Intradermal injection may cause skin irritation, infection, or necrosis.