A client has a prescription for heparin 1,000 units IV STAT. Several pre-filled syringes of low molecular weight heparin are available in the client's medication drawer. Which action should the nurse implement?

A. Request a prescription to change the route of administration and use the available heparin: Changing the route from IV to subcutaneous without provider approval is unsafe and can alter the onset, absorption, and effect of the drug. B. Dilute the available heparin in 250 mL of normal saline solution prior to IV administration: This is not appropriate for low molecular weight heparin, which is not interchangeable with unfractionated heparin and is not administered via continuous IV infusion. C. Calculate and administer the equivalent dose of the available low molecular weight heparin: Low molecular weight heparin (e.g., enoxaparin) differs in pharmacokinetics, bioavailability, and dosing from unfractionated heparin. They are not directly interchangeable, and substitution without provider approval is unsafe. D. Advise the pharmacy of the need to deliver a vial of heparin to the nursing unit immediately: The STAT order specifies unfractionated heparin IV, so the nurse must obtain the correct formulation promptly. Contacting the pharmacy ensures the right drug and route are available for timely administration.