OBJECTIVETo investigate the effects of electroacupuncture on bispectral index (BIS) of electroencephalography in patients undergoing subtotal thyroidectomy.

METHODSSixty patients were equally randomized into group A given electroacupuncture combined with cervical plexus block (CPB) and group B given CPB alone. After needling sensation was reached in bilateral "Hegu" and "Neiguan" acupoints, 5 min of high frequency electrical stimulation by electrical stimulation device followed with CPB was applied to group A, while only CPB was performed in group B. Visual analog scale (VAS) and verbal stress scale (VSS) were monitored, complication and adverse reaction were observed and BIS, mean arterial pressure (MAP), heart rate (HR) and arterial oxygen saturation (SaO2) were monitored continuously in the perioperative period.

RESULTSHR increased and BIS decreased in group A, both were lower significantly than those in group B (P < 0.01); MAP, the complementary dosage of fentanyl and lidocaine used and scores of VAS and VSS were also lower in group A than those in group B (P < 0.01).

CONCLUSIONElectroacupuncture could enhance the anesthetic effect of CPB, lower the BIS value during subtotal thyroidectomy.