Effect of transcutaneous electrical acupoint stimulation on the EC(50) of remifentanil suppressing responses to tracheal extubation in elderly patients

Transcutaneous electrical acupoint stimulation (TEAS) is a emerging treatment which combines transcutaneous electrical nerve stimulation with traditional acupoint therapy. The present study was aimed to evaluate the effect of TEAS on the effective concentration (EC(50)) of remifentanil suppressing tracheal extubation response in elderly patients. Fifty-three patients undergoing spine surgery were randomly divided into 2 groups: control group (group C, n = 26) and transcutaneous electrical acupoint stimulation group (group TEAS, n = 27). The EC(50) values for remifentanil TCI were determined using sequential method and probit analysis. The remifentanil EC(50) of that suppressed responses to extubation during anesthetic emergence was 1.20 ng/mL in group TEAS, a value that was significantly lower than the 1.64 ng/mL needed by patients in group C. The TEAS can enhance the efficacy of remifentanil on suppressing responses to tracheal extubation in elderly patients, the EC(50) of remifentanil can reduce approximately 27% compared with group C.