One consequence of hypernatremia is swelling of tissues in the brain. dangerously diluted blood sodium levels. rapid drop in blood pressure. movement of water into the intracellular fluid compartment.

The answer would be: swelling of tissues in the brain.

Hypernatremia is a condition when the blood natrium/sodium level is above normal. High natrium levels will increase the blood oncotic pressure, inducing osmosis of water between cells and the blood vessels. In the acute phase, hypernatremia shrinks the brain cells. The swelling will happens after the correction of natrium level.