What is the primary purpose of administering intravenous fluids with the insulin infusion in this patient?

• A. To hydrate and correct dehydration and hyperosmolarity
• B. To supply calories
• C. To prevent infection
• D. To directly lower blood glucose

Answer: (A)

The main idea is that fluids given with insulin are used to restore fluid volume and correct the dehydration and high plasma osmolality caused by severe hyperglycemia. When blood glucose is very high, the body loses lots of water through the kidneys (osmotic diuresis), which can leave an elderly patient dehydrated and with poor organ perfusion. Starting intravenous fluids helps rehydrate, improves blood pressure and kidney perfusion, and reduces the hyperosmolar state that can accompany high glucose. Insulin then lowers the glucose level, but without adequate fluids, the patient could become hypotensive or develop kidney injury as insulin shifts potassium into cells. In older adults, who are more prone to dehydration and electrolyte imbalances, addressing the volume status is the priority. Calories and infection prevention aren’t the primary goals of the IV fluids in this context, and lowering glucose is mainly the job of the insulin—the fluids support safe, effective insulin therapy by correcting dehydration and hyperosmolarity.