Acute effect of hemodialysis on sympathetic skin response

Sympathetic skin response (SSR) is a useful and simple test for unmyelinated axon function in peripheral sensorimotor neuropathies. SSR was tested on a group of patients undergoing chronic regular hemodialysis before and after a single dialysis session. Nineteen patients in hemodialysis for more than three months were included. Nine patients were on dialysis with cellulosic membranes (CA, 3 male and 6 female, aged 57.7 +/- 16.4 years) and ten ones were on dialysis with non-cellulosic membranes (NC, 4 male and 6 female, aged 50.2 +/- 15.9 years) were studied. There were no differences neither in Kt/V values (NC 1.37 +/- 0.34 vs. CA 1.22 +/- 0.27) nor in TAC ones (NC 41.5 +/- 18.2 vs. CA 41.3 +/- 14.1 mg/dL). After hemodialysis with NC amplitude significantly increased (994 +/- 1015 vs. 382 +/- 465 microv baseline, p < 0.05). Latency did not change (1.76 +/- 0.83 vs. 2.07 +/- 0.50 s baseline). After hemodialysis with CA neither amplitude changed (1368 +/- 1074 vs. 1240 +/- 1594 microv baseline), nor did latency (1.79 +/- 0.35 vs. 1.94 +/- 0.59 s baseline). Hemodialysis with non-cellulosic membranes (but not with cellulose acetate) yields a short-term improvement of sympathetic skin response. This effect is similar to those seen in nerve conduction velocities and it may be related to increased middle-molecules depuration.