Effectiveness of Mannitol vs Hypertonic Saline for Intracranial Hypertension from Traumatic Brain Injury

Since elevated ICP is complicated by higher mortality and serious neurologic deficits, its prevention and treatment are key. Osmotic agents can decrease cerebral edema and thus, ICP. This therapy is used in TBI patients who have clinical manifestations of cerebral edema and ICH or have a documented elevated ICP.3 Specifically, two osmotic agents, hypertonic saline (HTS) and mannitol (MNT), have been shown to be effective for ICP.3 Nonetheless, whether one agent is superior to the other has yet to be determined. Each osmotic agent has theoretical advantages. HTS has several theoretical advantages over MNT including intravascular volume replenishment and prevention of hypovolemia.3 Moreover, HTS appears to improve tissue oxygenation of the brain more than MNT since HTS has less chance of leaking into brain parenchyma and interfering with the functional tissue of the brain.3 A theoretical advantage of MNT is its effects on brain circulation. Although the mechanism of action of MNT isn’t fully understood, it is thought to lower ICP by reducing blood viscosity. This in turn helps cerebral blood flow and ultimately reducing cerebral blood volume and ICP.3 Additionally, MNT reduces ICP by withdrawing water from the brain parenchyma and is excreted in urine. 3 Examining the currently available evidence may establish which osmotic agent is more effective