Hyponatraemia.
< 135mmol/l.
Usually chronic in GP.
Most often euvolaemic, hypo-osmolar hyponatraemia.
Risk factors
- Old age / renal disease / hospitalisation /female.
Causes
- Medications - diuretics, SSRIs, opiods, NSAIDs, antipsychotics
- CHF / CLF /CRF / Hypothyroidism
- Dehydration - sport, infirmity.
- Excessive hydration - polydipsia, ecstacy, iv fluids
- SIADH - esp small cell lung ca.
- Adrenal insufficiency - Addisons,
> 125 correct, slowly
< 125 - admit
Assessment
- Water load status - euvolaemic, hypovolaemic, hypervolaemic.
- Check Serum osmolality (n > 275)
- Check urinary Na+ and urinary osmolality.