Hypertonic saline administration


These guidelines have been produced to guide clinical decision making for the medical, nursing and allied health staff of Perth Children’s Hospital. They are not strict protocols, and they do not replace the judgement of a senior clinician. Clinical common-sense should be applied at all times. These clinical guidelines should never be relied on as a substitute for proper assessment with respect to the particular circumstances of each case and the needs of each patient. Clinicians should also consider the local skill level available and their local area policies before following any guideline. 

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To guide staff in the administration of hypertonic saline.


  • The primary mechanism of action of hypertonic saline is rapid mobilisation of extravascular water into the intravascular compartment by creating a gradient in tonicity between the intravascular space and ECF
  • It may also improve cardiac effectiveness by increasing preload and by reducing after load due to hypertonic vasodilation of systemic and pulmonary vessels.


  • In ED, hypertonic saline is used for the correction of severe symptomatic hyponatraemia.


  • Central pontine myelinolysis due to rapid increase in serum Sodium (believed to be mainly associated with correction of chronic hyponatraemic states)
  • Volume overload
  • Hypernatraemia.


Sodium content of solutions  sodium (Mmol/L) 
3% saline  513 
20% saline  3400
  • 3% Saline is available in 1 litre bags
  • 20% Saline is available in 10ml ampoules


via Peripheral IV:

  • 3% Saline is the preferred solution
  • 6ml / kg raises the serum sodium approximately 5 mmol/l
  • Infusion rate: 3% Saline at 0.5 – 1.0 ml/kg/hr (max rate 100ml/hr)
  • Duration: administer over 1 hour 
  • Check serum Na hourly while infusion being administered and one hour post-completion of infusion.


  • Hypertonic Saline may cause thrombophlebitis, therefore caution should be exercised when giving via a peripheral cannula
  • Preferred method of delivery is via a central venous catheter
  • Do not give simultaneously with blood transfusions.


  1. The Extra Pharmacopoeia 35th Edition (2007) Martindale
  2. eMIMS 2012
  3. Australian Injectable Drugs Handbook 5th edition (2011)
  4. The Society of Hospital Pharmacists of Australia
  5. Shann, F. Drug Doses (2010) 15th edition
  6. Paediatric Dosage handbook international 17th Edition (2011)

Reviewer/Team: Meredith Borland (ED Director), Dennis Chow (ED Consultant), Deirdre Speldewinde (ED Consultant), Gabrielle Anstey (ED CNS), Craig Hasler (ED CNM)
Last reviewed: Apr 2018

Review date: Apr 2021
Endorsed by:

Director, Emergency Department Date:  Apr 2018

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