Transcutaneous electrical acupoint stimulation versus dexamethasone for prophylaxis of postoperative nausea and vomiting in breast surgery: A non-inferiority randomized controlled trial

Transcutaneous electrical acupoint stimulation and dexamethasone can reduce postoperative nausea and/or vomiting. In this noninferiority study, we compared the effects of Neiguan acupoint (PC6) transcutaneous electrical acupoint stimulation with dexamethasone to prevent postoperative nausea and/or vomiting in female patients undergoing breast surgery.In total, 280 patients were randomized into the following 2 groups: transcutaneous electrical acupoint stimulation (n = 140) and dexamethasone (n = 140). Transcutaneous electrical acupoint stimulation was performed 0.5 hours before anesthesia induction, immediately after entering the post-anesthesia care unit, and every 3 hours after leaving the post-anesthesia care unit. In the postoperative ward, the anesthetist instructed the patient's family members to assist the patient with PC6 patient-controlled transcutaneous electrical acupoint stimulation. Patients in the dexamethasone group were given 8 mg dexamethasone (intravenously) at 0.5 hours before induction of anesthesia. The incidence of nausea, vomiting, need for rescue antiemetics, patient satisfaction score, and the feasibility results of PC6 patient-controlled transcutaneous electrical acupoint stimulation were recorded 24 hours after surgery.Within 0 to 24 hours after surgery, the incidence of postoperative nausea and/or vomiting in the transcutaneous electrical acupoint stimulation group was not inferior to the dexamethasone group (31.1% vs 27.9%, per protocol risk difference 3.2; 95% confidence interval -7.7 to 14.0). The results of the intention-to-treat analysis (30.7% vs 27.1%, risk difference 3.6; 95% confidence interval -7.0 to 14.2) agreed with the per protocol analysis. Patient satisfaction score in the transcutaneous electrical acupoint stimulation group was higher than that in the dexamethasone group (3.9 ± 0.1 vs 3.6 ± 0.1, P = .003). The scheme of preventing postoperative nausea and/or vomiting by PC6 patient-controlled transcutaneous electrical acupoint stimulation was feasible.Transcutaneous electrical acupoint stimulation was noninferior to dexamethasone in preventing postoperative nausea and/or vomiting within 24 hours after breast surgery. Neiguan acupoint patient-controlled transcutaneous electrical acupoint stimulation was feasible to prevent postoperative nausea and/or vomiting.