Wrist-ankle acupuncture for preventing postoperative nausea and vomiting in high-risk female patients: study protocol for a pragmatic, randomized, single-blind, sham-controlled trial

Background Postoperative nausea and vomiting (PONV) affects approximately 30% of the general surgical population and up to 80% of high-risk patients, causing significant patient distress and dissatisfaction. Female gender, non-smoking status, history of motion sickness or previous postoperative nausea and vomiting, and opioid use represent established risk factors for developing these complications. Current pharmacological prophylaxis strategies may be insufficient for high-risk patients, and concerns about side effects and drug interactions limit their universal application. Wrist-ankle acupuncture (WAA), a specific form of acupuncture technique that stimulates points on the wrists and ankles, has shown promise as a non-pharmacological intervention for nausea and vomiting prevention. However, high-quality evidence from randomized controlled trials evaluating WAA specifically for PONV prophylaxis in high-risk populations remains limited. Methods This pragmatic, randomized, single-blind, sham-controlled trial will evaluate the effectiveness of WAA for PONV prophylaxis in high-risk female patients. Participants will be female patients aged 18–60 years with multiple PONV risk factors including non-smoking status, history of motion sickness or previous postoperative nausea and vomiting, and anticipated opioid use, scheduled for surgery under general anesthesia. Eligible participants will be randomly allocated to receive either WAA at specific acupoints (Upper 1, Lower 1, and Lower 2) or sham acupuncture using blunt-tip needles without skin penetration. The intervention will be administered within 30 minutes before anesthesia induction by trained practitioners. All participants will receive routine antiemetic prophylaxis according to current clinical guidelines. The primary outcome will be the incidence of PONV during the first 24 hours after surgery. Secondary outcomes will include nausea severity scores, vomiting frequency, rescue antiemetic requirements, patient satisfaction, and adverse events related to the intervention. Discussion This study will provide high-quality evidence regarding the effectiveness and safety of WAA as an adjunctive intervention for PONV prevention in high-risk female patients. The pragmatic design will enhance the generalizability of findings to routine clinical practice settings. If proven effective, WAA could offer a safe, non-pharmacological option to complement existing prophylactic strategies, potentially reducing the burden of PONV in vulnerable patient populations while minimizing additional drug-related side effects. Trial registration The trial was prospectively registered on the Chinese Clinical Trial Registry (ChiCTR2500096928) on February 10, 2025, before patient enrollment.