Adjunctive PC6 Stimulation Added to Dual Pharmacological Prophylaxis for Postoperative Nausea and Vomiting: A Randomised Clinical Trial

Background: Postoperative nausea and vomiting (PONV) remains common after laparoscopic surgery despite total intravenous anaesthesia and dual pharmacological prophylaxis. We aimed to assess whether adjunctive transcutaneous electrical acupoint stimulation (TEAS) at PC6 reduces PONV within 24 h in this setting. Methods: In this patient- and assessor-blinded, sham-controlled, randomised trial at a tertiary hospital in China, female adults at moderate to high risk of PONV scheduled for elective laparoscopic abdominal surgery were randomly assigned 1:1 to active PC6 stimulation or sham stimulation from 30 min before surgery until discharge from the post-anaesthesia care unit. All participants received total intravenous anaesthesia, dexamethasone, and ondansetron. The primary outcome was any PONV within 24 h after surgery, analysed in all randomised participants. The trial is registered with ClinicalTrials.gov, NCT06241547, and is completed. Findings: Between Feb 5, 2024, and Jan 9, 2026, 302 participants were randomly assigned to active stimulation (n=151) or sham stimulation (n=151). PONV within 24 h occurred in 48 (31.8%) of 151 participants in the active stimulation group and 52 (34.4%) of 151 in the sham group (absolute risk difference -2.6 percentage points, 95% CI -13.3 to 8.0; relative risk 0.92, 95% CI 0.67-1.27; p=0.71). No device-related adverse events were observed. Interpretation: Among female patients undergoing laparoscopic surgery and receiving total intravenous anaesthesia with dual pharmacological prophylaxis, adjunctive TEAS at PC6 did not significantly reduce 24-h PONV.