Last Modified: 1:21pm 16/04/2021

60 minutes to 6 hours


To achieve a gradual decline in osmolality (3-8 mosmol/kg/hr)

o Using 0.9% normal saline aim to give a further 0.5 – 1 L/hr depending on clinical assessment of dehydration / risk of precipitating heart failure and fluid balance (target is to achieve positive fluid balance of 2-3 L by 6 hours).

o Measure glucose, urea and electrolytes hourly and calculate osmolality (2Na+ + glucose + urea).

If plasma Na+:

Increasing but osmolality decreasing at appropriate rate, continue 0.9% sodium chloride.

Increasing AND osmolality increasing (or declining at less than 3 mosmol/kg/hr) check fluid balance. If positive balance inadequate increase rate of infusion of 0.9% sodium chloride.

If osmolality:

Increasing and fluid balance adequate, consider switching to 0.45% sodium chloride at same rate.

Decreasing at rate exceeding 8 mosmol/kg/hr consider reducing infusion rate  of IV fluids and/or insulin (if already commenced).

If blood glucose:

Falling less than 5 mmol/L per hour check fluid balance.

        If positive balance :

  • Inadequate increase rate of infusion of 0.9% sodium chloride
  • Adequate, commence low dose IV insulin (0.05 units/kg/hr) or if already running, increase rate to 0.1 units/kg/hr.

To maintain potassium in the normal range:

o Hypokalaemia (less than 3.5 mmol/L) and hyperkalaemia (greater than 6 mmol/L) are life threatening conditions and warrant senior review. They are less common in HHS than DKA but monitoring and replacement are essential.

Potassium level in first 24 hr (mmol/L) Potassium replacement in infusion solution
Over 5.5 Nil
3.5 – 5.5 40 mmol/L
Below 3.5  Senior review as additional potassium required

Avoidance of hypoglycaemia

o Aim to keep blood glucose 10-15 mmol/L in first 24 hours
o If blood glucose falls below 14 mmol/L commence 5% or 10% glucose at 125 ml/hr AND
CONTINUE 0.9% sodium chloride solution

• Monitor vital signs and chart Early Warning Score (EWS)
• Maintain accurate fluid balance chart (minimum urine output 0.5 ml/kg/hr)

JBDS Guidance