What substance might be administered to prevent cellular swelling in brain death donors?

Administering mannitol to prevent cellular swelling in brain death donors is based on its osmotic diuretic properties. Mannitol works by increasing the osmolarity of the blood, which draws water out of cells and into the bloodstream. This helps reduce intracranial pressure and prevents cellular edema, which is particularly important in cases of brain death where there may be compromised cellular integrity due to the lack of perfusion and oxygenation.

When brain death occurs, there is a risk of cellular swelling due to a variety of factors, including loss of autoregulation and increased intracranial pressure. By using mannitol, healthcare providers aim to mitigate these effects, preserving the organs for potential donation.

The other substances listed have different roles. For instance, vasopressin primarily acts on blood vessels to regulate blood pressure, dopamine influences cardiac output and renal function, and ephedrine is a stimulant that increases heart rate and blood pressure. None of these alternatives directly address the issue of cellular swelling to the same extent as mannitol does.