Certified Registered Nurse Anesthetist (CRNA) Practice Exam

What is the primary use of Mannitol in medical treatment?

1. To manage hypertension

2. To treat elevated intracranial pressure

3. To provide sedation during intubation

4. To enhance renal function

The correct answer is: To treat elevated intracranial pressure

Mannitol is primarily used in medical treatment for the management of elevated intracranial pressure. It is an osmotic diuretic that works by drawing fluid out of the brain and into the bloodstream, thereby reducing swelling and lowering pressure within the cranial cavity. This can be critical in conditions such as traumatic brain injury, stroke, or brain tumors, where control of intracranial pressure is vital to prevent further brain damage. The mechanism of action involves creating an osmotic gradient that encourages the movement of water from the intracellular space, where excess fluid might be causing edema, into the vascular compartment. This not only reduces intracranial pressure but can also improve cerebral blood flow and oxygen delivery to the brain. While Mannitol can have effects on renal function, such as promoting diuresis, its primary indication is certainly focused on addressing conditions related to elevated intracranial pressure. It is not routinely used for managing hypertension or for providing sedation during intubation, further consolidating its role specifically in neurocritical care scenarios.