SIADH, CSWS, and DI

Question 1

SIADH: its a state of what sodium state? urine osmolality? sodium secretion? serum osmolality?
It’s a condition of excess ____ and not a _____
Patients are usually ___volemic
What’s going on at the distal collecting tubules?

Answer 1

State of hypnatremia in combination with elevated urine osmolality, excessive sodium secretion and decreased serum osmolality.
Condition of excess water not sodium deficiency
Patients are usually hypervolemic
Cells secreting ADH are dysregulated and water absorption from the distal collecting tubules is enhanced

Question 2

Common causes of SIADH: whats the most common?

Answer 2

idiopathic-most common 
post operative 
Head trauma/ surgery 
Small cell lung cancer 
hypothyroidism 
Ecstasy, TCAS, SSRIs

Question 3

Signs and symptoms of SIADH

Answer 3

Anorexia, malaise, headache

Question 4

DDX for SIADh:

Answer 4

Adrenal insufficiency
CSWS
Polydipsia
DM

Question 5

Plasma osmolality and urine osmolarity in SIAdH

Answer 5

Plasma osmolality: <270

Urine osmolarity: usually greater than 100

Question 6

Make sure to exclude which diagnoses before making diagnosis of SIAdH

Answer 6

exclude hyperglycemia, hyperlipidemia and excess proteins

Question 7

Treatment for SIADH:

Answer 7

Treat underlying cause if possible
water restriction 800 mL -1,000 mL per day
Hypertonic saline if patient symptomatic
diuretics: furosemide (more water loss than sodium)
Demeclocycline-used for chronic cases when fluid restriction is difficult to maintain)

Question 8

What is cerebral salt wasting syndrome: State of ___natremia with increased ____ due to ___.
Excessive ___ excretion secondary to _____
Patients are usually what-vol status?

Answer 8

state of hyponatremia with increased natriuresis due to an intracranial pathology. Excessive sodium excretion secondary to a centrally mediated process. Usually dehydrated and hypovolemic

Question 9

Etiology of CSWS:

Answer 9

Head injury, intracranial tumor, meningitis, intracerebral bleed or stroke

Question 10

Signs and symptoms of CSWS:

Answer 10

Anorexia, n/v, malaise

Question 11

Ddx of CSWS:

Diagnosis of CSWS:

Answer 11

Ddx :Idiopathic hyponatremia, SIADH

Diagnosis: hyponatremia, dilute urine with a high flow rate, random urine sodium greater than 40 mEq/L

Question 12

Treatment of CSWS:

Answer 12

Treatment: fluids, correction of low sodium, fludrocortisone (mineralocorticoid)

Question 13

Diabetes insipidus is a state of what ____natremia?

Causes of DI?

Answer 13

Hypernatremia with a normal total body concentration of sodium
CentraL: surgical, neoplasm, meningitis
Nephrogenic: Drug effects: demeclocylcine, sickle cell
Polycystic kidney disease

Question 14

Signs and symptoms of DI:
DDX:
Diagnosis:

Answer 14

excessive urination and extreme thirst
ddx; untreated DM1, psychogenic polydipsia
Diagnosis: often made clinically, but can do a desmopressin stimulation test

Question 15

Treatment of DI:

Answer 15

Central: desmospressin, hydration
Nehrogenic: thiazides (decreases sodium resorption), adequate hydration

Question 16

If patients with CSWS, SIADH or DI go to OR, what monitor do you for sure need?

Answer 16

Foley

Question 17

Hyponatremai associated with SIADH should be corrected with hypertonic saline in which patients? Rate of correction?

Answer 17

Corrected with hypertonic saline in its with sodium less than 110 or those who are symptomatic, should be corrected at less than 0.5 mEq/L/hr. Should not exceed 15mEq/L in 24 hours