[The role of the venous reservoir in maintaining arterial pressure during hemodialysis. Effect of dihydroergotamine].

Hemodialysis has been reported to produce a decrease in cardiac output partially related to a peripheral relocation of blood volume. In order to further evaluate this hypothesis, the hemodynamic effects of dihydroergotamine (DHE), a veino-constrictor drug, were investigated in 5 patients undergoing hemodialysis. Body weight, total blood volume, arterial blood pressure, cardiac output and heart rate were obtained before (period A) and immediately after hemodialysis: before (period B) and after an acute infusion of DHE (period C); studies were performed in supine then in tilted position. During period B, cardiac index decreased by 27% (p less than 0.05) and stroke index by 35% (p less than 0.02). Acute infusion of DHE produced a significant increase in cardiac index (+ 18%, p less than 0.05), stroke index (+ 28%, p less than 0.05) and blood pressure (+ 20%, p less than 0.05). These results indicate that the hemodynamic alterations induced by hemodialysis may be partially reversed by contraction of the capacitance system following DHE infusion.