“…1,4,7,8,11,15,20,28,29,32 SIADH is generally regarded as a hypo-osmolar hyponatremic state characterized by inappropriate free water retention, subsequent onset of natriuresis, and euvolemia. 1,4,7,8,15,32 The principal defining feature distinguishing the entities is the patient's volume status, with CSW identified by high urine output and hypovolemia. 1,5,[7][8][9]15,17,21,25 Other markers of volume status, including heart rate, central venous pressure (CVP), hemoconcentration, red blood cell or plasma volume, and abbreviations CSW = cerebral salt wasting; CVP = central venous pressure; DDAVP = desmopressin; IQR = interquartile range; RR = relative risk; SIADH = syndrome of inappropriate antidiuretic hormone secretion.obJective Cerebral salt wasting (CSW) and the syndrome of inappropriate antidiuretic hormone secretion (SIADH) cause postoperative hyponatremia in neurosurgery patients, can be difficult to distinguish clinically, and are associated with increased morbidity.…”