What is the mechanism by which 5% dextrose in water worsens intracranial pressure in neurosurgical patients?

What is the mechanism by which 5% dextrose in water worsens intracranial pressure in neurosurgical patients?

• A. Free water diffusion into brain tissue after glucose metabolism
• B. Increased blood viscosity
• C. Decreased cerebral blood flow
• D. Increased CSF production

Answer: (A)

Free water from the dextrose-containing solution is left behind after the glucose is metabolized, which lowers plasma osmolality. That hypotonic fluid then shifts into brain tissue, where water moves into cells and interstitial spaces, causing cerebral edema. In neurosurgical patients, the closed skull limits expansion, so this brain swelling raises intracranial pressure. This is why 5% dextrose in water can worsen ICP.

Free water from the dextrose-containing solution is left behind after the glucose is metabolized, which lowers plasma osmolality. That hypotonic fluid then shifts into brain tissue, where water moves into cells and interstitial spaces, causing cerebral edema. In neurosurgical patients, the closed skull limits expansion, so this brain swelling raises intracranial pressure. This is why 5% dextrose in water can worsen ICP.