Final answer:
Nurse Allyson should first discontinue the IV line in a patient with phlebitis. This initial step helps in preventing further irritation and reduces the risk of severe complications. Other supportive actions can follow after the IV line has been removed.
Step-by-step explanation:
When caring for a patient with clinical manifestations of phlebitis, Nurse Allyson's priority action should be to discontinue the IV line. Phlebitis is inflammation of a vein, often caused by an indwelling venous catheter, which can result in pain, swelling, redness, or warmth along the vein. Discontinuing the IV can prevent further irritation and reduce the risk of complications such as infection or thrombosis. Subsequent actions may include elevating the affected limb to decrease swelling, applying warm compresses to the area to alleviate discomfort, and administering medications as prescribed. However, these are secondary to removing the source of irritation. Note: Administering anticoagulants may be indicated if there is evidence of thrombosis, but this would not be the first step in managing phlebitis without such evidence.