What is the recommended dose of 3% normal saline (hypertonic saline) for managing raised intracranial pressure (ICP)?

Dosing of 3% Normal Saline for Raised Intracranial Pressure

For managing raised intracranial pressure (ICP), administer 3% hypertonic saline as a continuous infusion with a target serum sodium concentration of 145-155 mmol/L. 1

Bolus Dosing

• For acute management of elevated ICP, administer 5 ml/kg of 3% hypertonic saline over 15-20 minutes 1, 2
• Alternatively, a 250 ml bolus of 7.5% hypertonic saline can be used for more rapid ICP reduction, administered over 15-20 minutes 1, 3
• The maximum effect of hypertonic saline is observed after 10-15 minutes and lasts for 2-4 hours 1

Continuous Infusion Protocol

• Following bolus administration, continuous infusion of 3% hypertonic saline is recommended to maintain ICP control 3
• Target serum sodium concentration should be 145-155 mmol/L 1, 3
• The mean effective dose to achieve ICP below 15 mmHg is approximately 1.4 ml/kg 4

Monitoring Requirements

• Measure serum sodium levels within 6 hours of bolus administration 3, 1
• Do not re-administer hypertonic saline until serum sodium concentration is < 155 mmol/L 3
• Monitor for hypernatremia and hyperchloremia, especially with continuous infusions 1
• Continuous ICP monitoring is recommended during therapy 1

Instructions for ICU Staff

• Administer initial bolus of 5 ml/kg of 3% hypertonic saline over 15-20 minutes for acute ICP elevation 2, 5
• Follow with continuous infusion at a rate titrated to maintain serum sodium between 145-155 mmol/L 1, 3
• Check serum sodium levels every 6 hours during the first 24 hours of therapy 3
• Discontinue or reduce infusion rate if serum sodium exceeds 155 mmol/L 3, 1
• Monitor hemodynamic parameters, as hypertonic saline may cause a transient increase in mean arterial pressure 4

Efficacy and Safety Considerations

• 3% hypertonic saline has been shown to be effective in reducing ICP in traumatic brain injury and subarachnoid hemorrhage (Grade A evidence) 3
• Studies have demonstrated that 3% hypertonic saline maintains better hemodynamic stability compared to mannitol 2, 4
• No evidence of osmotic demyelination syndrome has been reported with proper monitoring 3, 1
• Despite effectiveness in reducing ICP, there is no evidence that hypertonic saline improves neurological outcomes (Grade B) or survival (Grade A) 3, 1

Important Caveats

• Hypertonic saline should be used instead of and not in conjunction with mannitol for this indication 3, 1
• 3% hypertonic saline may have a longer duration of action compared to other concentrations or mannitol 6
• In pediatric patients with raised ICP, 3% hypertonic saline has shown significant benefits in decreasing coma hours 5
• Avoid rapid or excessive correction of serum sodium to prevent complications 1