Impact of bilateral ST36 and PC6 electroacupuncture on the depth of sedation in general anaesthesia.

OBJECTIVE: To investigate the impact of electroacupuncture (EA) at bilateral acupuncture points ST36 and PC6 on the level of sedation in general anaesthesia.

METHODS: 40 patients undergoing abdominal surgery were randomly divided into two groups: EA combined with general anaesthesia (EA group, n=20) and general anaesthesia control group (n=20). The bilateral acupuncture points ST36 and PC6 were selected in both groups. Target-controlled infusion (TCI) of propofol was used for the induction and maintenance of general anaesthesia to reach an equilibrium state of Narcotrend Index (NT index). In the EA group, EA was performed with a Hans EA device. In the control group, general anaesthesia was performed without EA stimulation. In both groups, heart rate (HR), mean blood pressure (MAP) and NT index were recorded at corresponding time points up to 30 min after the end of acupuncture.

RESULTS: The NT indices of the EA group showed a downward trend after EA stimulation (p=0.01). From 15 min after the start of EA stimulation the NT indices of the EA group were significantly lower than those of the control group (p<0.05). HR and MAP of the two groups showed no significant differences at any time points (p≥0.05).

CONCLUSIONS: EA stimulation at bilateral ST36 and PC6 significantly deepens the sedation level of general anaesthesia in patients with propofol TCI, has little impact on haemodynamics and provides significant delayed sedation effects.