Which of the following is a potential consequence of correcting sodium too rapidly in a patient with hypernatremia?

• A. Seizure
• B. Hyperkalemia
• C. Cerebral edema
• D. Hyperglycemia

Answer: (C)

Rapidly lowering the sodium level in hypernatremia causes a dangerous osmotic shift. The brain adapts to high extracellular osmolality by accumulating osmolytes to prevent cells from shrinking. If you correct sodium too quickly, extracellular osmolality drops faster than brain cells can readjust, and water rushes into brain cells. That influx swells the brain, raising intracranial pressure and leading to cerebral edema, which can cause severe neurologic symptoms.

Hyperkalemia and hyperglycemia aren’t direct results of this rapid osmotic shift. Seizures can occur with cerebral edema, but the hallmark and most anticipated consequence of over Rapid correction is cerebral edema.