Escalate to senior team member: registrar

Acute Hypernatremia 

Aim: replace water deficit in 24 hours (2, 4)

• Correct cause and replace fluid deficit

1. Oral fluid replacement^ (if able) OR
2. IV glucose 5%
   • Rate: 3-6mL/kg/hr 

• Replace ongoing free water losses
• Monitor serum Na 1-2 hourly until <145mmol/L

If over/undercorrection noted escalate to senior team members

• Osmotic demyelination is rare in acute hypernatremia (as no time for cerebral adaptation) (4)

Monitor for hyperglycaemia

Chronic Hypernatremia

Aim: lower serum Na by 10mEq/L in 24 hours (2, 4)

• Correct cause and replace fluid deficit

1. Oral fluid replacement^ (if able) OR
2. IV glucose 5% (see below for rate calculation)

• Replace ongoing free water losses
• Monitor serum Na 4-6 hourly
  • Once target correction rate reached, monitor 12-24 hourly

If over/undercorrection noted escalate to senior team members

• Undercorrection
  • Increase rate of glucose infusion
• Overcorrection
  • May require hypotonic 0.45% normal saline as even slow rates of glucose may be too much (4, 6)
  • CALL OUT BOX:
    • 0.45% normal saline sodium content is 154 mmol/L
    • If serum sodium is >154 mmol/L, administering normal saline will still lower the level, slower than dextrose

Monitor for hyperglycaemia and any change in neurological signs or symptoms (escalate if noticed)

Diabetes Insipidus: TO BE ESCALATED TO ENDOCRINOLOGY FOR EXPERT ADVICE

• Desmopressin* (1, 3, 4, 5)
• Regulation of water intake (If impaired thirst sensation)