When entering the skin and cannulating a vein, the usual needle position is:

Choice A reason: Charting is important for documentation but not the priority before transfusion. Verifying blood product identification prevents life-threatening transfusion reactions, such as hemolytic reactions, which can occur from mismatched blood types.
Choice B reason: Monitoring for pain is irrelevant, as pain is not a primary concern during transfusion initiation. Ensuring correct blood product identification prevents severe reactions like hemolysis, which can cause organ damage or death.
Choice C reason: Verifying blood product identification ensures the correct blood type is administered, preventing hemolytic transfusion reactions. Mismatched blood can cause immune-mediated hemolysis, leading to severe complications, including renal failure or shock, making this the priority.
Choice D reason: Reviewing allergies is important but secondary to verifying blood product identification. Allergic reactions are less severe than hemolytic reactions from mismatched blood, which pose immediate life-threatening risks during transfusion.

Choice A reason: Starting a new IV site allows administration of incompatible medication without mixing with the primary fluid, preventing chemical reactions that could alter drug efficacy or cause precipitation, ensuring safe delivery.
Choice B reason: Administering slowly with a syringe does not address incompatibility. Mixing with the primary fluid risks precipitation or inactivation, potentially causing emboli or reduced therapeutic effect, making this method unsafe.
Choice C reason: Not administering the medication avoids incompatibility but delays treatment, which may harm the patient. Alternative methods, like a new IV site or flushing, ensure safe delivery without withholding necessary therapy.
Choice D reason: Flushing with sterile water is inappropriate, as it is hypotonic and may cause hemolysis or fluid shifts. Normal saline is the standard flush to maintain catheter patency and prevent drug interactions during administration.
Choice E reason: Flushing with 10 mL of normal saline before and after administration clears the catheter of incompatible fluids, preventing precipitation or drug inactivation. Saline maintains isotonicity, ensuring safe and effective medication delivery.