Objective:To evaluate the effect of transcutaneous electrical acupoint stimulation (TEAS) on emergence agitation in the patients undergoing thoracoscopic surgery.Methods:Eighty patients of both sexes, aged 25-64 yr, with body mass index of 18-30 kg/m 2, of American Society of Anesthesiologists physical status Ⅱ or Ⅲ, undergoing elective thoracoscopic surgery under general anesthesia, were divided into 2 groups ( n=40 each) by a random number table method: TEAS group (group T) and control group (group C). In group T, the Hegu (L14), Zusanli (ST36) and Sanyinjiao (SP6) were stimulated starting from 30 min before induction of anesthesia until the end of operation, with a frequency of 2/100 Hz and disperse-dense waves.The intensity of stimulation was the maximum current that patients could tolerate.In group C, stimulating electrodes were placed at the same acupoints before induction, but no electrical stimulation was applied.Ramsay sedation score and VAS score were recorded.and emergence agitation was assessed using RSS agitation score.Blood samples from the median cubital vein or internal jugular vein were collected before anesthesia induction (T 1), at the end of surgery (T 2), immediately after removal of tracheal tube (T 3) and at 15 min after removal of tracheal tube (T 4) for determination of serum interleukin-6 (IL-6) and IL-10 concentrations by enzyme-linked immunosorbent assay.The intraoperative consumption of propofol, remifentanil and sufentanil was recorded.Adverse reactions such as tachycardia, bradycardia, hypertension, hypotension, respiratory depression, delay of awakening and nausea and vomiting were recorded after operation. Results:Compared with group C, the amount of intraoperative remifentanil consumed was significantly decreased, serum IL-6 concentrations were decreased, and the serum IL-10 concentration was increased T 2-4, Ramsay sedate score was increased, and the incidence of agitation was decreased in group T ( P<0.05). There was no significant difference in VAS score and incidence of postoperative adverse reactions between the two groups ( P>0.05). Conclusions:TEAS can reduce the development of emergence agitation in the patients undergoing thoracoscopic surgery, which is related to inhibition of inflammatory responses.