When do you consider starting hypertonic saline solution in patients with an acute ischemic stroke?

Hypertonic (3%) saline is infrequently used, and mainly applies to patients who have signs of significant midline shift or cerebral edema on CT or MRI with a depressed loss of consciousness. In stroke patients in the awake/alert state with a large stroke and risk for edema development in the next 24-48 hours, treatment can be initiated if hyponatremia is also present. Higher concentrations of hypertonic saline (23%) are used when there is impending herniation as an alternative to mannitol, and lower concentrations (2%) are unlikely to provide benefit over normal saline or a similar infusion.