Should Hypertonic Saline Be Considered for the Treatment of Intracranial Hypertension? A Review of Current Evidence and Clinical Practices

Abstract

Intracranial hypertension (IH) is a critical neurological emergency that requires prompt intervention because failure to treat it properly can lead to severe outcomes, including secondary brain injury. Traditionally, mannitol (MNT) has been the cornerstone of hyperosmolar therapy. However, the use of hypertonic saline (HTS) has become increasingly important because of its unique advantages. Both HTS and MNT effectively reduce intracranial pressure by creating an osmotic gradient that draws fluid from brain tissue. However, unlike MNT, HTS does not induce diuresis or significantly lower blood pressure, making it more favorable for maintaining cerebral perfusion. Additionally, HTS does not cause rebound edema and carries a lower risk of renal injury than MNT. However, it is important to note that the use of HTS comes with potential risks, such as hypernatremia, hyperchloremia, and fluid overload. Due to its unique properties, HTS is a crucial agent in the management of IH, and understanding its appropriate use is essential to optimize patient outcomes.

Keywords: Brain edema; Intracranial hypertension/drug therapy; Mannitol; Saline solution, hypertonic.

FIGURE 1. Mechanism of actions of hypertonic saline. HTS reduces cerebral edema and decreases ICP through its osmotic effect, as well as plasma expansion and improved cerebral microcirculation. Additionally, the cardiovascular effects of HTS increase intravascular volume and cardiac output, leading to an elevation in CPP. Moreover, HTS possesses immune-modulating and antioxidant properties. Together, these mechanisms work synergistically to contribute to the prevention of secondary brain injury.

HTS: hypertonic saline, IV: Intravenous, BP: blood pressure, ICP: intracranial pressure, CPP: cerebral perfusion pressure.