Breast cancer is one of the three most common cancers worldwide, and the primary treatment method is surgery.Since most patients are non-smokers who use opioids in the postoperative period, which are known risk factors for postoperative nausea and vomiting (PONV) according to the Apfel Risk Score. Breast surgery was identified as a strong risk factor for PONV. According to the previous studies, the incidence of PONV is 30-70% in patients undergoing the breast cancer surgery, which not only gives patients unpleasant and painful experience, but also prolongs the hospital stays and delay patient discharge and adds to hospital costs. We compared the effects of dexamethasone alone vs. in combination with Pericardium 6 (P6) electrical stimulation or granisetron for inhibition of PONV in women undergoing breast cancer surgery.

186 patients who are planed to undergo elective breast cancer surgery under general anaesthesia into the following three groups: acupoint stimulation+dexamethasone (Group Acu, n=62), granisetron +dexamethasone (Group Gra, n=62), and dexamethasone alone (Group Dxm, n=62). The incidence of nausea, vomiting, and need for rescue antiemetics was recorded 2, 6, 24, and 48 h after surgery.

Inclusion Criteria:

• women undergoing breast cancer resection under general anesthesia
• aged between 18 to 65
• American Society of Anesthesiologists grade I-II

Exclusion Criteria:

• using antiemetic drugs within 24 h before operation,
• nausea or vomiting within 24 h before operation;
• Alcoholic or drug abuse,
• abnormal liver and/or kidney function, diabetic or peripheral neuropathy patients, cardiovascular disease (excluding those with controlled hypertension).
• refuse to participate clinical trial