Hyponatremia

Question 1

How does hyponatremia causes brain to swell

Answer 1

When plasma sodium levels are low (low plasma oncotic pressure), water leaves plasma into cells causing swelling

Question 2

Why are symptoms developed in hyper or hyponatremia symptoms related to the CNS

Answer 2

It can cause brain swelling and brain shrinking

Question 3

What are some symptoms seen in sodium electrolyte disorders

Answer 3

Malaise
Stupor
Coma
Nausea

Question 4

Osmolality should be ………. in hyponatremia

Answer 4

Low

Question 5

What is the key solute to determine plasma osmolality

Answer 5

Sodium

Question 6

What is the first step in the evaluation of hyponatremia

Answer 6

Make sure that serum osmolality is low

Question 7

What could be the cause of a hyponatremia which presents with high osmolality

Answer 7

Hyperglycemia or mannitol in plasma which raise plasma osmolality

Question 8

What could be some causes of a hyponatremia which presents with a normal osmolality

Answer 8

Artifact in serum Na measurement
Hyperlipidemia
Hyperproteinemia (multiple myeloma)
Pseudohyponatremia

Question 9

What is the normal osmolality of urine

Answer 9

50-1200 mOsm/kg

Question 10

What is the urine osmolality in hyponatremia

Answer 10

< 100mosm/kg

Question 11

What is the urinary sodium in hyponatremia

Answer 11

< 30meq/L