The nurse suspects that a patient's intravenous solution has infiltrated into the tissues.What action should the nurse take first?

A) Aspirate,then inject 0.5 mL normal saline.
B) Restart the IV line in a different vein.
C) Stop the infusion immediately.
D) Notify the primary care provider.

The first action the nurse should take when suspecting an infiltration is to stop the infusion immediately to prevent further infiltration and damage to the tissues. Aspirating and injecting normal saline should be done after stopping the infusion, and restarting the IV line may not be necessary if the current vein is still suitable for IV access. Notification of the primary care provider may need to be done eventually, but it is not the first priority action.