Why are IV fluids critical in the management of NMS?

• A. Prevent acute kidney injury from rhabdomyolysis
• B. Lower blood pressure
• C. Treat infection
• D. Increase urine output for diuresis

Answer: (A)

Aggressive IV hydration is essential in NMS because severe muscle breakdown (rhabdomyolysis) can overflow the kidneys with myoglobin, risking acute kidney injury. When muscles are damaged, myoglobin enters the bloodstream and can clog the renal tubules, leading to acute tubular necrosis. Providing large amounts of isotonic IV fluids helps maintain renal perfusion and flushes myoglobin through the urine, supporting kidney function and helping achieve a protective urine output (often targeted around 0.5–1 mL/kg/hr). While diuresis may occur as a result, the main reason for IV fluids is to prevent kidney injury from rhabdomyolysis. The other options aren’t the primary goal here—NMS isn’t treated primarily as an infection, and lowering blood pressure isn’t the central purpose of this intervention, though fluids can aid overall stabilization.