Management of Water and Sodium Disturbances after Transsphenoidal Resection of Pituitary Tumors.

Patients with pituitary masses who undergo transsphenoidal resection are at risk for a number of medical complications postoperatively. Among these are disturbances in fluid and sodium homeostasis, including diabetes insipidus (DI) and syndrome of inappropriate secretion of antidiuretic hormone (SIADH). It is believed that these pathologic states are a result of damage to the hypothalamic-pituitary axis from surgery, as are the downstream consequences, such as the triple phase response. The triple-phase response describes the pattern of initial acute DI, subsequent rebound SIADH, and eventual chronic DI, the pathophysiology of which is described. Given the medical complexity of managing postoperative pituitary patients, it is essential to develop dedicated postoperative management protocols. Here, we describe the University of Utah's postoperative pituitary management protocol that includes immediate postoperative monitoring, treatment of DI, surveillance for the triple-phase response after discharge with outpatient serum sodium checks, and involvement of the endocrinology service for assistance with management of hypopituitarism. A complete understanding of the relevant anatomy, physiology, and development of standardized protocols for postoperative management can aid with minimizing medical complications after pituitary surgery.