Mechanisms of Increased Ambulatory Blood Pressure in Patients With Intradialytic Hypertension

The purpose of this study is 1) to determine what physiologic factors (extracellular fluid overload or vasoconstriction) contribute more to increased blood pressure levels between dialysis treatments in hemodialysis patients whose blood pressure increases and decreases during hemodialysis and 2) to determine whether carvedilol provides better control of blood pressure between dialysis treatments than prazosin in patients whose blood pressure increases during dialysis.