Abstract
This study was carried out by using the Valsalva maneuver to evaluate autonomic nerve function in hemodialysis patients. We examined five normotensive and five hypotentive dialysis patients including one with striato-nigral degeneration.The Valsalva maneuver, which consists of forced expiration against 40mmHg for 15 seconds, was performed with continuous recording of arterial pressure and electrocardiography.The ratio of the R-R intervals was significantly lower in hypotensive than normontensive patients (1.24±0.16vs 1.47±0.14, P<0.05). The changes in arterial pressure during strain and release were significantly lower in hypotensive than normotensive patients (Strain: 53.00±2.74vs 73.00±13.03mmHg, P<0.01, Releare: 43.00±8.37 vs 90.00±14.14mmHg, P<0.001).Moreover, the absence of arterial pressure overshoot (phase IV) was specific in hypotensive patients and this finding was similar to that in striato-nigral degeneration with autonomic dysfunction.
These results indicate that autonomic insufficiency is one of the factors in the hypotension in patients undergoing long-term hemodialysis.
