Which medication may be given for blood pressure support before dialysis in patients experiencing hypotension?

Midodrine is a medication specifically designed to treat orthostatic hypotension, which is a form of low blood pressure that occurs when standing up. It functions as a vasopressor by stimulating alpha-adrenergic receptors, leading to vasoconstriction, which increases blood pressure. In the context of dialysis, patients may experience hypotension due to factors like fluid shifts or removal of blood during the procedure. Administering midodrine before dialysis can help support their blood pressure, ensuring better tolerance of the treatment and minimizing the risk of complications associated with low blood pressure.

The other options listed, while they are medications used for various cardiovascular conditions, do not have the same application for immediate blood pressure support in the pre-dialysis context. Amlodipine, a calcium channel blocker, is primarily used to lower blood pressure, while Losartan, an angiotensin receptor blocker, also works to reduce blood pressure and would not be appropriate for immediate support in hypotensive situations. Furosemide, a diuretic, is typically used to reduce fluid overload but may exacerbate hypotension by leading to further volume depletion. Thus, midodrine is the most suitable choice for providing acute blood pressure support before dialysis.