SIADH

Question 1

SIADH causes

Answer 1

CNS disorders, CNS disorders, infection, hypothyroidism, trauma, ectopic ADH ( small cell, pancreatic cancer), drugs, stroke

Question 2

drugs that cause SIADH

Answer 2

CARDISH, chemo, antidepressant, rec drugs, diuretics, inhibitors (ACEI), sulfonylurea, hormones (desmopressin)

Question 3

pathophysis

Answer 3

ADH -> water retention -> no RAAS -> no na reabsorption -> hyponatremia

aquaporin channels adapt -> maintain euvolemic state

Question 4

investigations for SIADH

Answer 4

hyponatremia, low serum osmo, high urine osmo, high urine na, euvolemic, normal thyroid function, normal adrenal function

Question 5

symptoms of SIADH

Answer 5

cerebral oedema, pulmonary oedema, seizures, headaches, vomiting

Question 6

treatment

Answer 6

fluid restriction, 3% hypertonic saline 100ml, loop diuretic, check U+E every 4 hours, demeclocycline (ADH agonist, democratic donkey cycling), tolvaptan