Nature: Excessive loss of hypotonic urine Treatment: Fluid resuscitation greater than urine output Cause Central (Failed ADH secretion) Idiopathic (30%) CNS (60%) Tumour 25% Pituitary surgery, Sheehan’s, panhypopituitarism (20%) Head trauma (15%) CNS infection CVA, Aneurysm Sickle cell anaemia Respiratory…