Final answer:
The greatest risk for someone receiving mannitol IV is fluid overload, which can result in symptoms from edema to life-threatening pulmonary edema.
Step-by-step explanation:
The greatest risk for someone receiving mannitol IV is c) Fluid overload. Mannitol is an osmotic diuretic, which means it increases the osmotic pressure of blood, leading to the movement of fluid from tissues into the bloodstream, thus increasing blood volume. While this might seem beneficial in managing cerebral edema or reducing intraocular pressure, it can be detrimental if it leads to fluid volume overload. This condition is characterized by symptoms ranging from mild edema to severe and life-threatening pulmonary edema. Patients with conditions like heart failure, liver cirrhosis, some kidney diseases, hyperaldosteronism, and certain glucocorticoid steroid treatments are at an increased risk of developing hypervolemia if excess water and sodium are retained.