Hyponatraemia Flashcards
Approaching electrolyte abnormalities
Symptoms
Severity
Timeline
Intravascular volume
Symptoms
Confusion mod Nausea Vom severe Seizures LOC Cerebral oedema Coma, Resp arrest, Death
Insidious confusion
Chronic hyponatraemia
Severity
<135 mild
<130 moderate
<125 severe
Chronic hyponatraemia
Risk of poor outcome if correction is too quick
Timeline
Is it acute or chronic?
Determining fluid status
In exam:
Dry-> hypovolaemic
Normal -> euvolaemic
Wet -> hypervolaemia
Urine
Check urine sodium
Paired osmolality:
Check urine osmolality + blood osmolality
High blood osmolality
Lab mistake: with lots of fat/protein/Ig
High blood sodium
.?
Serum osmolality
Should be 275 - 295 normally
Should be low if hyponatraemic
Hypovolaemic causes
.?
Diuretics which cause hyponatraemia
Thiazides diuretics -> stop diuretic allow it to increase alone
Management of severe acute hyponatraemia
3% saline
Check again in an hour
4-6 mmol increase in a few hours
No >10 in trust 24 hrs!!
Osmotic demyelination syndrome
Central pontine demyelination
If sodium rises too quickly Confusion Dysarthria Dysphasia Locked in syndrome