ABSTRACT
Transsphenoidal pituitary surgery is frequently complicated with mild to severe water and electrolyte disturbances in the postoperative period. These disorders are: transient diabetes insipidus, early or delayed hyponatremia, diabetes insipidus followed by hyponatremia (biphasic pattern), diabetes insipidus-hyponatremia-diabetes insipidus (triphasic pattern), permanent diabetes insipidus, and cerebral salt-wasting syndrome. Close monitoring of water intake, urine output, thirst, volume status and serum electrolytes is imperative, and a dynamic treatment plan according to the changing status of the patient is mandatory. This review will focus on the types, course and treatment of water and electrolyte disturbances observed after transsphenoidal pituitary surgery.