FN: Hyponatraemia

Question 1

Presentation

Answer 1

.

Question 2

Presentation

Answer 2

.

Question 3

Causes

Answer 3

Hypovolaemia
Hypervolaemic
Euvolaemic

Question 4

Hypovolaemia

Answer 4

U Na >20 mM (=renal loss)

U Na >20mM (=extra-ranal loss)

Question 5

U Na >20 mM hypovolaemia = renal loss causes

Answer 5

Diuretics
Addisons
Osmolar diuresis (e.g. glucose)
Renal failure (diuretic phase)

Question 6

Hypervolaemia hyponatraemia causes

Answer 6

Cardiac failure
Nephrotic syndrome
Cirrhosis
Renal failure

Question 7

Hypervolaemia hyponatraemia causes

Answer 7

Cardiac failure
Nephrotic syndrome
Cirrhosis
Renal failure

Question 8

Causes

Answer 8

Hypovolaemia
Hypervolaemic
Euvolaemic

Question 9

Hypovolaemia

Answer 9

U Na >20 mM (=renal loss)

U Na >20mM (=extra-ranal loss)

Question 10

U Na >20 mM hypovolaemia = renal loss causes

Answer 10

Diuretics
Addisons
Osmolar diuresis (e.g. glucose)
Renal failure (diuretic phase)

Question 11

U Na >20 mM hypovolaemia = extra renal loss

Answer 11

Diarrhoea
Vomiting
Fistula
SBO
Burns

Question 12

Hypervolaemia hyponatraemia causes

Answer 12

Cardiac failure
Nephrotic syndrome
Cirrhosis
Renal failure

Question 13

Euvolaemic U osmolality >500

Answer 13

SIADH

Question 14

Euvolaemia U osmolality

Answer 14

Water overload
Severe hypothyroidism
Glucocorticoid insufficiency

Question 15

Management

Answer 15

• correct underlying cause
• Replace Na and water at the same rate they were lost
• asymptomatic chronic hyponatraemia - fluid restrict
  -S ymptomatic/acute/dehydrated - cautious rehydration with 0.9% Ns
  If hypervolaemia consider frusomide
  Emergency seizures/coma: consider hypertonic saline (e.g. 1.8%)

Question 16

Replace sodium too fast

Answer 16

central pontine myelinolysis

Question 17

Chronic Na loss replacement

Answer 17

10mM/d

Question 18

Acute Na loss replacement

Answer 18

1mM/hr

Question 19

SIADH

Answer 19

• Concentrated urine: Na>20mM, osmolality >500

- Hyponatraemia or plasma osmolality

Question 20

SIADH causes

Answer 20

Resp: SCLC, pneumonia, TB
CNS: meningoencephalitits, head injury, SAH
Endo: hypothyroidism
Drugs: cyclophosphamide, SSRIs, CBZ

Question 21

SIADH Rx

Answer 21

Treat cause and fluid restrict

Vasopression recepto antagonists

Question 22

Vasopressin receptor antagonist name (2)

Answer 22

• Demclocycline

- Vaptans