Severe Hyponatraemia in the ED
An excellent approach (& F/U Podcast) by Weingart (EMCRIT)….
…….When they are <130 is when I get a little worried
Step I-Send Lots of Labs
Serum-electrolytes, osmolality, uric acid (if on diuretics), and you might as well send a TSH and cortisol as well (if you have any suspicion of an endocrine cause)
Urine-UA, urine lytes, urine urea, urine uric acid (if on diuretics), urine osm, urine creatinine
Step II-Treat CNS dysfunction
If the patient is altered, comatose, seizing, or has neurologic findings, then raise the sodium by a little bit
Give 3% saline, 100 ml over 10-60 minutes (2 cc/kg up to a max of 100 cc)
- 10 minutes later, may repeat X 1
- may be given peripherally through any reasonable IV
- each 100 ml will raise sodium by ~2 mmol/l
Step III-Hang tight
- Do not feel the need to do anything else, just fluid restrict the patient
- Place a foley catheter
- Do not feel tempted to give NS
- Do not be clever, just fluid restrict and admit.
- Patients are at a fall risk with hyponatremia
- Get a CT scan if they are still a little wacky
- Be incredibly careful when correcting hypokalemia, potassium repletion will raise the Na
- Remember the rules of 6’s (from the Stern article below)
Step IV-What to do when you couldn’t follow step III
- dDAVP 1-2 mcg IV or SubQ x 1
- Consult renal
- Consider D5W 6ml/kg over 1 hour in consultation with renal if you have really screwed up
