What are the two osmotic agents commonly used to remove fluid from the brain?

Mannitol and hypertonic saline are effective osmotic agents used to reduce cerebral edema by drawing fluid out of the brain into the intravascular space. Mannitol is a sugar alcohol that increases osmotic pressure in the blood, which causes fluid to move from the brain tissues and into the bloodstream, helping to decrease intracranial pressure.

Hypertonic saline also works on the principle of osmotic pressure, where it has a higher sodium concentration than normal blood serum. This draws water out of the brain cells and into the extracellular space, effectively reducing swelling. Together, these two agents are often utilized in clinical settings to manage conditions like traumatic brain injury or stroke, where controlling intracranial pressure is critical for patient outcomes.

Other options may include agents that do not have the same dual effect of effectively pulling fluids out of the brain or might not be commonly used in this particular context. For instance, glucose is primarily a source of energy and does not serve as an osmotic agent for fluid removal in the same way that mannitol and hypertonic saline do.