CCM 77: SIADH

Question 1

List the 6 reported causes for SIADH in dogs

Answer 1

• neoplasia
• meningoencephalitis
• aspiration pneumonia
• hydrocephalus
• liver disease
• GA

Question 2

How much does the ECV have to decrease to cause ADH release from the posterior pituitary?

Answer 2

5-10%

Question 3

List the 5 diagnostic criteria for SIADH

Answer 3

• hypoosmolar hyponatremia
• euvolemia
• inappropriately concentrated urine (urine osmolality > 100 mOsm/L)
• urine Na cc > 30 mmol/L
• ruled out Addison’s

Question 4

What are common causes for elevated ADH levels in critically ill patients?

Answer 4

• pain
• nausea
• anesthesia
• surgery

Question 5

What is the treatment for SIADH in hospital?

Answer 5

• water restriction
• diuretic administration (low dose e.g., lasix at 0.1-0.5 mg/kg)
• vasopressin receptor antagonist (vaptans) –> more established in human medicine