How do changes in serum sodium affect the nervous system?
Because extracellular fluid volume changes as a direct function of total body sodium, patients who are hyponatremic are usually hyposmolar, whereas hypernatremic patients are hyperosmolar.
Neurologic manifestations of sodium dysregulation mainly result from shrinkage or swelling of the brain, and the degree to which these changes occur depends both on the amount and the rapidity of the sodium changes.
