Garrett was admitted to the hospital after sustaining an injury. While waiting for skin-graft surgery, he received fluids through a needle inserted directly into his vein. Garrett was most likely being treated for

Fluids given through a needle directly into a vein are intravenous fluids, often used to replace fluid lost after severe burns. Skin-graft surgery is also commonly used to treat deep, third-degree burns, which damage the full thickness of the skin. So Garrett was most likely being treated for third-degree burns.

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