What are the guidelines for using hypertonic saline (hypertonic sodium chloride solution) in hospital settings?

Guidelines for Hypertonic Saline Use in Hospitals

Hypertonic saline should be used as first-line hyperosmolar therapy for reducing intracranial pressure in hospitalized patients with acute intracranial hypertension, administered as a 7.5% solution at 250 mL bolus over 15-20 minutes, with a target serum sodium of 145-155 mmol/L. 1

Primary Indications

Raised Intracranial Pressure (Grade A Recommendation)

Hypertonic saline is effective at reducing intracranial pressure and should be used instead of—not in conjunction with—mannitol. 2, 1

• Bolus dosing: 7.5% hypertonic saline at 250 mL administered over 15-20 minutes is the most commonly recommended formulation 2, 1
• Alternative concentrations studied include 1.7% to 30% saline, with higher concentrations (23.5%, 30%) used in specific scenarios 2
• Maximum ICP-lowering effect occurs at 10-15 minutes and lasts 2-4 hours 1
• Three randomized controlled trials comparing hypertonic saline to mannitol showed significant benefit with hypertonic saline 2

Continuous Infusion Protocol

• 3% hypertonic saline as continuous infusion is recommended for pediatric traumatic brain injury and can be used in adults 2, 1
• Target serum sodium concentration: 145-155 mmol/L 1
• Mean treatment duration in pediatric studies was 7.6 days without adverse effects 2, 1
• Continuous infusions validated for prevention of intracranial hypertension in acute liver failure 2

Monitoring Requirements

Serum Sodium Surveillance

Measure serum sodium within 6 hours of bolus administration and do not re-administer until serum sodium is <155 mmol/L. 1

• Majority of patients have peak sodium levels <155 mmol/L after bolus therapy 2, 1
• Avoid sodium levels exceeding 155-160 mmol/L to prevent complications 1
• Monitor fluid, sodium, and chloride balances to prevent hypernatremia and hyperchloremia 1
• Highest recorded sodium level in a survivor was 169 mmol/L, with most levels returning to normal by 24 hours 2

Safety Monitoring

• No evidence of osmotic demyelination syndrome has been reported with proper monitoring, even with bolus doses of 23.4% hypertonic saline 1
• MRI and autopsy studies in patients receiving high-dose hypertonic saline showed no evidence of osmotic demyelination syndrome 2
• Continuous intracranial pressure monitoring is recommended when using hypertonic saline 1

Administration Routes and Safety

Central vs. Peripheral Access

• Central intravenous administration may be preferred for hypertonic saline 3
• Peripheral intravenous administration is safe provided measures are undertaken to detect and prevent phlebitis and extravasation 3
• Proper protocols, education, and institutional safeguards must be in place for safe use 3

Specific Clinical Scenarios

Traumatic Brain Injury

• Nine randomized controlled trials in TBI patients demonstrated efficacy, with four comparing to mannitol showing three with significant benefit for hypertonic saline 2
• Bolus doses of 250 mL are standard unless otherwise specified 2
• Pediatric TBI patients: 1.7% to 3% continuous infusions targeted at elevated sodium levels 2

Subarachnoid Hemorrhage

• 7.2% hypertonic saline with 6% hydroxyethyl starch or 23.5% hypertonic saline boluses effectively reduce ICP 2
• Three studies included SAH patients with confirmed ICP reduction 2

Hemorrhagic Shock

Hypertonic saline is effective for blood pressure restoration in hemorrhagic shock but NOT recommended for routine volume resuscitation. 2, 1

• Grade A evidence supports blood pressure restoration in hypovolemic shock 2
• No survival benefit demonstrated with hypertonic saline in shock states 2
• May be considered in combined hemorrhagic shock with severe head trauma and focal neurological signs due to osmotic effect 1

Severe Symptomatic Hyponatremia

• Hypertonic saline is recommended for treating severe and symptomatic hyponatremia 4
• General consensus exists that hypertonic saline should be used in patients with moderate or severe symptoms to prevent neurological complications 5

Critical Limitations

Mortality and Neurological Outcomes

Despite effectiveness in reducing intracranial pressure, there is no evidence that hypertonic saline improves neurological outcomes (Grade B) or survival (Grade A) in patients with raised intracranial pressure. 2, 1

• No survival benefit demonstrated in shock states (Grade A) 2
• Australian randomized trial showed no difference in ICP control or neurological outcome at 6 months in pre-hospital TBI resuscitation 2
• Insufficient evidence from randomized controlled trials to confirm improved neurological outcomes in adults with acute intracerebral hemorrhage 1

Common Pitfalls to Avoid

• Do not use hypertonic saline in conjunction with mannitol—use instead of mannitol 2, 1
• Do not exceed serum sodium of 155-160 mmol/L to prevent complications 1
• Do not use for routine volume resuscitation in hemorrhagic shock 1
• Avoid rapid or excessive sodium correction to prevent osmotic demyelination syndrome 1
• Do not re-administer bolus until serum sodium is confirmed <155 mmol/L 1

Contraindications and Special Populations

• 4% albumin solution should be avoided in patients with brain injury as it may increase mortality 1
• Caution advised with high osmolar loads due to increased risks of hypernatremia or osmotic blood-brain barrier opening 6
• Concentrations above 10% may open tight junctions in the blood-brain barrier 2