A clinical study of persistent hypotension in patients on chronic hemodialysis

: In order to clarify the pathogenesis of hypotension seen in the patients on chronic hemodialysis, we studied the vascular reactivity to exogenous vasoactive substances and the change of plasma ANP level during hemodialysis treatment. The vascular responsiveness to intravenously infused norepinephrine was decreased in hemodialysis patients, particularly in hypotensive group, compared with healthy controls (< 0.05). The blood pressure response to angiotensin II was also diminished significantly in hypotensive patients, compared with normotensive patients (p < 0.05). The plasma ANP concentration before and after each hemodialysis treatment was not different statistically between hypotensive and normotensive patients. Furthermore, the change of plasma ANP concentration was not correlated with the blood pressure change during each hemodialysis procedure. These findings suggest that the decrease of vascular responsiveness may be a factor for causing persistent hypotension in patients on chronic hemodialysis, and that the plasma ANP level is not responsible for the pathogenesis of hypotension.