A nurse is assessing a client's peripheral IV during hourly rounding. The nurse notices the site has erythema, warmth, edema, and a red line traveling up the vessel. Which complication would the nurse identify this client has?

The correct answer is A: Thrombophlebitis. Thrombophlebitis is characterized by inflammation of the vein with symptoms such as erythema, warmth, edema, and a red line traveling up the vessel. The red line indicates the presence of a blood clot, causing the vein to become inflamed. Infiltration (B) is the leakage of IV fluids into surrounding tissues, presenting with swelling and pallor. Infection (C) would show signs of localized redness, pain, and possibly purulent drainage. Extravasation (D) is the leakage of vesicant medications causing tissue damage, not inflammation of the vein.