A client receiving IV fluids develops redness, warmth, and pain at the insertion site. The LVN should suspect:

Rationale: A. Fluid volume overload is incorrect because it affects the whole circulatory system, not just the IV site. Signs include edema, hypertension, distended neck veins, dyspnea, and crackles in the lungs, not localized redness, warmth, or pain at the insertion site. B. Infiltration is incorrect because infiltration occurs when non-vesicant IV fluid enters the surrounding tissue. It usually presents as cool skin, swelling, and pallor around the site, not warmth and redness. C. Extravasation is incorrect because extravasation involves leakage of vesicant (tissue-damaging) medications into surrounding tissue, causing pain, swelling, and possible tissue necrosis. While some signs overlap, redness and warmth alone without tissue damage is more characteristic of phlebitis. D. Phlebitis is correct because phlebitis is inflammation of the vein. It is characterized by redness, warmth, swelling, pain along the vein, and sometimes a palpable cord. Causes include mechanical irritation from the catheter, chemical irritation from IV fluids or medications, or infection. Prompt recognition and action, such as removing the IV, applying warm compresses, and monitoring for infection, are necessary to prevent complications.