Treatment of Cerebral Salt Wasting

Introduction to Cerebral Salt Wasting

The American Association of Neurological Surgeons recommends aggressive volume and sodium replacement with isotonic or hypertonic saline for cerebral salt wasting (CSW), as fluid restriction can worsen outcomes and increase the risk of cerebral ischemia 1, 2

CSW is characterized by hypovolemia with clinical signs of volume depletion, such as hypotension, tachycardia, dry mucous membranes, and CVP <6 cm H₂O, whereas SIADH is characterized by euvolemia with no edema, normal skin turgor, moist mucous membranes, and CVP 6-10 cm H₂O 1, 3
Both conditions show inappropriately high urinary sodium (>20 mmol/L) and high urine osmolality (>500 mOsm/kg) 3

For severe symptomatic CSW, the American College of Neurological Surgeons recommends transfer to ICU for close monitoring, administration of 3% hypertonic saline to correct 6 mmol/L over 6 hours or until severe symptoms resolve, and addition of fludrocortisone 0.1-0.4 mg daily to reduce renal sodium losses 1, 2, 3
For mild to moderate CSW, the American College of Neurological Surgeons recommends isotonic saline (0.9% NaCl) at 60-100 mL/h for volume repletion, or oral sodium chloride 100 mEq three times daily if the patient can tolerate oral intake 1, 2

The American Association of Neurological Surgeons recommends never using fluid restriction in subarachnoid hemorrhage (SAH) patients at risk for vasospasm, as it can result in cerebral infarction 1, 3
Consider hydrocortisone to prevent natriuresis in SAH patients 1, 3

Daily weights and strict intake/output monitoring are recommended 1
Serum sodium should be monitored every 2 hours for severe symptoms, every 4 hours after symptom resolution, and then daily 1, 2
Watch for osmotic demyelination syndrome, typically 2-7 days after rapid correction 2, 3

The formula for calculating sodium deficit is: Desired increase in Na (mEq/L) × (0.5 × ideal body weight in kg) 1