A nurse is preparing to administer heparin subcutaneously to a client who has a deep vein thrombosis. Which technique is correct?

A. Aspiration for blood return is contraindicated when administering subcutaneous heparin because it increases the risk of local tissue trauma and hematoma formation. Pulling back on the plunger can create a vacuum that ruptures small capillaries in the adipose tissue. This mechanical stress leads to unnecessary bruising and may interfere with the predictable absorption of the anticoagulant. B. Massaging the injection site after heparin administration is strictly avoided as it can cause significant ecchymosis and tissue irritation. Physical manipulation of the site accelerates the spread of the medication into damaged capillaries, potentially leading to a localized hemorrhage. The nurse should avoid any friction or pressure that could disrupt the integrity of the subcutaneous vascular network. C. The Z-track method is a specific technique reserved for deep intramuscular injections to prevent medication leakage into subcutaneous tissues. It is not used for subcutaneous administration of heparin, which is specifically designed for absorption within the fatty layer. Utilizing this method for heparin would be an incorrect application of parenteral technique and would not mitigate the risk of bruising. D. Correct administration involves cleansing the skin, inserting the needle into the subcutaneous layer, and injecting the medication without aspiration or subsequent massage. Applying gentle pressure after needle withdrawal helps prevent the leakage of blood or medication from the puncture site. This technique minimizes the risk of hematoma and ensures the anticoagulant is delivered safely into the intended tissue plane.