The maintenance of normal plasma osmolality depends on the interaction of some complex mechanisms that regulates the extracellular fluid and sodium levels, involving antidiuretic hormone (ADH) actions, thirst, and the renin-angiotensin-aldosterone system. The hyponatremia may be caused by salt depletion, dilution mechanisms, or metabolic disturbances and is a frequent occurrence after the pituitary surgery, affecting 9 to 35% of these patients. Its causes can be the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) or, more frequently, the cerebral salt-wasting […]
