What is the use of hypertonic saline (sodium chloride) solution?

From the Guidelines

Hypertonic saline should be used to reduce intracranial pressure in traumatic brain injury and subarachnoid haemorrhage, but it does not improve neurological outcomes or survival benefit in these patients. The use of hypertonic saline in critical care has been evaluated in several studies, including a review of the literature and guidelines for use in hypotensive states and raised intracranial pressure 1. According to this review, hypertonic saline solutions are effective at reducing intracranial pressure in conditions causing acute intracranial hypertension, but there is no survival or outcome benefit with the use of hypertonic saline solutions for raised intracranial pressure.

Key Points

• Hypertonic saline is effective in reducing raised intracranial pressure (Grade A) 1
• It does not improve neurological outcomes (Grade B) nor survival in states of raised intracranial pressure (Grade A) 1
• The majority of studies have used 7.5% hypertonic saline boluses, while continuous infusions usually utilize 3% hypertonic saline 1
• Hypertonic saline should be used instead of and not in conjunction with mannitol for the treatment of raised intracranial pressure 1

Administration and Monitoring

• For increased intracranial pressure, bolus doses of 250 mL of 3% solution or 30 mL of 23.4% solution may be given 1
• Hypertonic saline should be administered through a central venous catheter when possible, especially at higher concentrations 1
• Close monitoring of serum electrolytes, fluid status, and neurological function is required 1

Adverse Effects

• Fluid overload, pulmonary edema, central pontine myelinolysis (if sodium is corrected too rapidly), phlebitis, and electrolyte imbalances are potential side effects of hypertonic saline 1
• Safety concerns of studies have included autopsies performed on patients 1

From the FDA Drug Label

INDICATIONS AND USAGE: Sodium Chloride Injection, USP, 23. 4%, is indicated as an additive in parenteral fluid therapy for use in patients who have special problems of sodium electrolyte intake or excretion. The answer to the question about Hypertonic saline is that it is indicated for the treatment of sodium, chloride and water deficiencies that commonly occur in many diseases, as stated in the drug label for sodium chloride (IV) 2.

• The drug label mentions that Sodium Chloride Injection, USP, 23. 4% is intended to meet the specific requirements of the patient with unusual fluid and electrolyte needs.
• Key words include: sodium electrolyte intake, parenteral fluid therapy, and treatment of sodium deficiencies.

From the Research

Uses of Hypertonic Saline

• Hypertonic saline is used to treat several critical conditions such as severe and symptomatic hyponatremia and increased intracranial pressure 3
• It is also used in the management of acute traumatic brain injury to reduce intracranial pressure 4
• Hypertonic saline has been shown to be effective in controlling elevated intracranial pressure and as a resuscitative agent in multiple settings including traumatic brain injury (TBI) 5
• The primary indications for the use of hypertonic saline in critical care are hyponatremia, volume resuscitation, and brain injury 6

Administration of Hypertonic Saline

• Hypertonic saline can be administered through a central venous catheter (CVC) or peripherally 3
• Peripheral administration of 3% hypertonic saline is considered a safe and possibly preferred option as it carries a low risk of complications and is a less invasive procedure compared to CVC 3
• The overall incidence of complications associated with peripheral infusion of 3% hypertonic saline is low, with infiltration occurring in 3.3%, phlebitis in 6.2%, erythema in 2.3%, edema in 1.8%, and venous thrombosis in 1% of cases 3

Efficacy and Safety of Hypertonic Saline

• Hypertonic saline has been shown to be effective in reducing elevated intracranial pressure in patients with traumatic brain injury 4
• The effectiveness of hypertonic saline compared with other ICP-lowering agents in the management of acute TBI is still debated, both in the short and the long term 4
• There is weak evidence to suggest that hypertonic saline is no better than mannitol in efficacy and safety in the long-term management of acute TBI 4
• Hypertonic saline appears to be safe and effective in controlling elevated ICP during the inpatient course, but significant questions remain as to the dose and manner of HTS infusion 5