Vascular responsiveness and body fluid status in patients on chronic hemodialysis.

The vascular responsiveness and the body fluid distribution were studied in 5 hypotensive and 11 normotensive patients on long-term hemodialysis. A diminished vascular responsiveness to intravenously infused norepinephrine or angiotensin II was found in uremic patients, especially in the hypotensive group. A slightly larger, but non-significant circulating blood volume (CBV) and a less extracellular fluid volume (ECF) was found in the hypotensive group as compared with those of the normotensive group. These results suggest that with autonomic nervous dysfunction, such a diminution of vascular responsiveness may be an another factor responsible for the development of hypotension.