What is the recommended administration method for hypertonic saline (HS) in managing intracranial hemorrhage (ICH), infusion or boluses?

Hypertonic Saline Administration for Intracranial Hemorrhage

For intracranial hemorrhage with elevated intracranial pressure, use continuous infusion of 3% hypertonic saline targeting serum sodium 145-155 mmol/L as the primary strategy, reserving bolus doses (7.5% hypertonic saline, 250 mL over 15-20 minutes) for acute ICP crises. 1, 2

Administration Strategy

Continuous Infusion (Primary Method)

• Administer 3% hypertonic saline as continuous infusion targeting serum sodium concentration of 145-155 mmol/L 1, 2
• This approach is specifically recommended by the American Society of Anesthesiologists for patients with intracerebral hemorrhage 1
• Continuous infusion provides sustained ICP control and may have longer duration of action compared to bolus therapy 3
• In a retrospective study of 100 patients with severe cerebrovascular disease (including intracerebral hemorrhage), early continuous 3% hypertonic saline infusion reduced ICP crises (92 vs 167 episodes, p=0.027) and decreased in-hospital mortality (17.0% vs 29.6%, p=0.037) 4

Bolus Therapy (For Acute ICP Elevation)

• Use 7.5% hypertonic saline at 250 mL per bolus administered over 15-20 minutes for threatened intracranial hypertension or signs of brain herniation 1
• Alternative bolus dosing: 5.3 mL/kg of 3% hypertonic saline infused over 15-20 minutes 2
• Maximum effect occurs at 10-15 minutes and lasts 2-4 hours 1, 2
• Bolus therapy produces immediate ICP reduction but requires repeated dosing when effect wanes (typically every 163±54 minutes) 5

Rationale for Infusion Over Boluses

The evidence favors continuous infusion as the primary strategy for several reasons:

• Sustained ICP control: Continuous infusion maintains stable serum sodium and osmolality, preventing the rebound ICP elevations that can occur between bolus doses 1
• Reduced frequency of ICP crises: The retrospective study showed fewer total episodes of elevated ICP with continuous infusion strategy 4
• Longer duration of action: In experimental ICH models, 3% NaCl maintained significantly lower ICP at 120 minutes compared to pretreatment values, while mannitol did not 3
• Guideline support: The American Society of Anesthesiologists specifically recommends continuous infusion for intracerebral hemorrhage patients 1

Monitoring Requirements

Serum Sodium Monitoring

• Measure serum sodium within 6 hours of any bolus administration 1, 2
• Do not re-administer bolus until serum sodium is <155 mmol/L 1, 2
• Target range: 145-155 mmol/L; avoid exceeding 155-160 mmol/L to prevent complications 1, 2

Additional Monitoring

• Monitor fluid, sodium, and chloride balances to prevent hypernatremia and hyperchloremia 1
• Continuous ICP monitoring is recommended when using hypertonic saline for intracerebral hemorrhage 1

Comparative Efficacy

• Hypertonic saline is more effective than mannitol at equiosmolar doses for ICP reduction 1, 6
• Meta-analysis of 8 prospective RCTs showed higher rate of treatment failure with mannitol versus hypertonic saline 6
• In ICH models, 3% NaCl produced significantly higher cerebral perfusion pressure (108.4±4 vs 79.6±10 mmHg, p=0.048) and lower water content in lesioned white matter compared to mannitol 3
• A study in aneurysmal subarachnoid hemorrhage found 3% hypertonic saline and 20% mannitol equally effective, but hypertonic saline should be considered first-line 7

Critical Limitations and Caveats

Despite effectiveness in reducing ICP, there is no evidence that hypertonic saline improves neurological outcomes (Grade B) or survival (Grade A) in patients with raised intracranial pressure 8, 1, 2

Safety Considerations

• Avoid rapid or excessive sodium correction to prevent osmotic demyelination syndrome 1, 2
• No evidence of osmotic demyelination syndrome has been reported with proper monitoring, even with sustained hypernatremia 1, 2
• Hypertonic saline is not recommended for volume resuscitation in hemorrhagic shock unless combined with severe head trauma and focal neurological signs 1, 2

Common Pitfalls

• Avoid using hypertonic saline in conjunction with mannitol—use one or the other, not both 1
• Do not exceed target sodium of 155 mmol/L to prevent complications 1, 2
• Ensure adequate monitoring infrastructure before initiating therapy 1

Clinical Algorithm

1. Initiate continuous infusion of 3% hypertonic saline targeting serum sodium 145-155 mmol/L for all ICH patients with elevated ICP 1, 2
2. For acute ICP crises during continuous infusion, administer bolus of 7.5% hypertonic saline 250 mL over 15-20 minutes 1
3. Check serum sodium within 6 hours of any bolus administration 1, 2
4. Do not repeat bolus until serum sodium <155 mmol/L 1, 2
5. Continue monitoring ICP, serum sodium, and clinical status throughout treatment 1