Transcutaneous electrical nerve stimulation on the PC-5 and PC-6 points alleviated hypotension after epidural anaesthesia, depending on the stimulus frequency

Abstract

Neuraxial blockade causes arterial hypotension. Transcutaneous electrical nerve stimulation (TENS) at the Neiguan (PC-6) and Jianshi (PC-5) reduces the severity of hypotension after spinal anaesthesia, but did not clarify the optimal stimulus frequency. We hypothesized that the stimulus frequency of TENS at the PC-6 and PC-5 points would influence the severity of hypotension after epidural anaesthesia. 65 ASA I or II male patients presenting for inguinal hernia repair were randomized to five groups: the control group received no treatment; the 2Hz, 10Hz, 20Hz, and 40Hz groups received TENS at a frequency of 2Hz, 10Hz, 20Hz, and 40Hz, respectively. The lowest SBP was significantly higher in the 40Hz group [the control, 84 (74-110)mmHg; the 2Hz, 96 (62-116)mmHg; the 10Hz, 100 (68-110)mmHg; the 20Hz, 96 (64-115)mmHg; the 40Hz, 104 (75-140)mmHg: P = 0.004]. Significantly less patients experienced hypotension in the 40Hz group [the control, 78; the 2Hz, 43; the 10Hz, 38; the 20Hz, 38; the 40Hz, 8: P = 0.008]. TENS on the PC-6 and PC-5 points reduced the severity and incidence of hypotension after epidural anaesthesia, depending on the stimulus frequency. Copyright 2012 Young-Chang P. Arai et al.