Hypertonic Saline (HTS) 3%

  • Hypertonic Saline (HTS) 3% is a concentrated solution of sodium chloride which can be used to treat severe, symptomatic hyponatraemia (< 120 mmol) as well as being the preferred treatment for raised intracranial pressure secondary to TBI as it is less likely to cause the hypotension associated with use of Mannitol1. HTS exerts an osmotic effect on swollen cerebral tissue and the extracellular space to help control intracranial pressure in an attempt to reduce the effects of secondary brain injury.
  • 3% HTS comes in 250mL bags
  • 6ml/kg will raise the serum sodium by approximately 5mmol/L

Traumatic Head Injury with a GCS ≤ 8 AND one or more of the following:

  • Fixed dilated pupils
  • Unilateral neurological signs
  • Hypertension (SBP >160mmHg) with bradycardia (PR <60)
  • GCS deterioration of further 2 points whilst in care of SJA

Severe, symptomatic hyponatraemia with a measured sodium level of < 120 mmol/L AND one or more of the following:

  • GCS ≤ 8
  • Seizures
  • Vomiting
  • None when used in accordance with these guidelines
 Precautions / Notes
  • Transfusion of packed red blood cells must be independent of a HTS infusion
 Weight-based Calculations
Cefazolin for fractures/prophylaxis
Presentation: /mL
Calculated dose:  in

Critical Care
Traumatic Brain Injury
  • 5ml/kg bolus dose IV over 10 - 20 minutes.
  • Single dose only


ASMA approval required for all paediatric cases
  • 5ml/kg bolus dose IV over 10 – 20 minutes
  • Single dose only
Severe, symptomatic hyponatraemia
  • 1ml/kg bolus dose over 30 minutes
  • Repeat as necessary to obtain Na level to ≥ 125mmol/L


ASMA approval required for all paediatric cases
  • 0.5 – 1mg/kg over 1 hour
 Special Considerations

Side effects:

  • Phlebitis
  • Volume overload
  • HTS induced hypernatraemia
  • Osmotic demyelination syndrome
  • Hypertonic Saline (HTS) 3% in 250ml soft plastic bag
Hypertonic Saline (HTS) 3%
Current mode:
Extended Care:
Colour assist:


Marko N. F. 2012. Hypertonic saline, not mannitol, should be considered gold-standard medical therapy for intracranial hypertension. Critical care;16(1), 113. https://doi.org/10.1186/cc11182

Surgical Critical Care – Hypertonic Saline bolus. www.surgicalcriticalcare.net/guidelines/hypertonic%2-Saline%202020.pdf

Hypertonic Saline Guideline. 2018. www.SORT.nhs.uk

Hypertonic Saline Administration. 2018. PCH guidelines. https://pch.health.wa.gov.au 

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Clinical Services

Responsible Manager
Head of Clinical Services


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