Intraoperative opioid-sparing effect of different duration transcutaneous electrical acupoint stimulation in video-assisted thoracoscopic lobectomy

Abstract

Objective To evaluate the intraoperative opioid-sparing effect of different duration transcutaneous electrical acupoint stimulation (TEAS) in video-assisted thoracoscopic lobectomy. Methods Seventy-five patients, aged 18-64 yr, weighing 40-96 kg, of ASA physical status Ⅰ or Ⅱ, scheduled for elective video-assisted thoracoscopic lobectomy under general anesthesia, were randomly divided into 3 groups (n=25 each) using a random number table: control group (group C) , 30 min of stimulation before induction of anesthesia group (group B) , and stimulation throughout surgery (group T) . In group B, the patients received TEAS (frequency 2/100 Hz) on acupoints Xinshu (BL15) , Feishu (BL13) , Neiguan (PC6) , Hegu (LI4) on the operated side starting from 30 min before induction of anesthesia until the beginning of induction, and the intensity was the maximum current that could be tolerated.The intensity for Neiguan (PC6) and Hegu (LI4) was 6-12 mA, and for Xinshu (BL15) and Feishu (BL13) was 9-18 mA.In group T, the patients received TEAS on the four acupoints mentioned above starting from 30 min before induction of anesthesia until the end of surgery.The patients had the electrodes applied, but received no stimulation in group C. After anesthesia was induced with propofol-sufentanil-cisatracurium, double lumen endotracheal tube was inserted.Propofol was given by target-controlled infusion to maintain BIS value within the range of 40-60.Cisatracurium was infused continuously to facilitate muscle relaxation.The infusion rate of remifentanil was adjusted to maintain analgesia nociception index value within the range of 50-70.The intraoperative consumption of remifentanil (the intraoperative consumption of sufentanil was converted to the consumption of remifentanil producing the equivalent effect by 1∶10) was recorded. Results Compared with group C, the intraoperative consumption of remifentanil was significantly decreased in B and T groups.The intraoperative consumption of remifentanil was significantly lower in group T than in group B. Conclusion TEAS on Xinshu (BL15) , Feishu (BL13) , Neiguan (PC6) and Hegu acupoints throughout surgery and for 30 min before induction of anesthesia significantly reduces intraoperative opioid consumption in the patients undergoing video-assisted thoracoscopic lobectomy, while TEAS throughout surgery provides better effect. Key words: Transcutaneous electric nerve stimulation; Analgesics, opioid; Pneumonectomy; Dose-response relationship, drug