Efficacy of Transcutaneous Auricular Vagus Nerve Stimulation for Postoperative Pain Relief in Patients Undergoing Elective Laparoscopic Gastrointestinal Tumor Surgery

Pain Ther. 2026 Mar 13. doi: 10.1007/s40122-026-00825-y. Online ahead of print.

ABSTRACT

INTRODUCTION: Acute postoperative pain remains prevalent among patients undergoing gastrointestinal tumor surgery. The study was conducted to evaluate the efficacy of transcutaneous auricular vagus nerve stimulation (taVNS) in alleviating postoperative pain in this population.

METHODS: This patient- and assessor-blinded randomized controlled trial was conducted at the Second Affiliated Hospital of Zhejiang University School of Medicine. Eligible participants who underwent elective laparoscopic gastrointestinal tumor surgery were randomly assigned to the taVNS or control stimulation group. Both groups received the stimulation on the day before surgery and the day after surgery. The primary outcome was the change in visual analogue scale (VAS) scores at 24 h postoperatively.

RESULTS: The median reduction in VAS scores was 12.0 in the taVNS group, compared with 5.0 in the control stimulation group (median [interquartile range, IQR] 12.0 [10.0-13.3] mm vs 5.0 [2.0-8.0] mm; P < 0.001). Additionally, the taVNS group showed lower cumulative morphine milligram equivalents (MME) at 48 h (median [IQR] 0 [0-5] mg vs 5 [0-10] mg; P = 0.004) and 72 h (median [IQR] 0 [0-5] mg vs 5 [0-10] mg; P = 0.002), and shorter time to first flatus (median [IQR] 45 [40-60] h vs 75 [60-85] h; P < 0.001). The incidence of complications, length of hospital stay, and quality of recovery-15 (QoR-15) scores are similar between groups.

CONCLUSION: TaVNS statistically alleviated postoperative pain in patients undergoing gastrointestinal tumor surgery, decreased analgesic requirements, and promoted gastrointestinal function recovery.

TRIAL REGISTRATION: NCT06763913.

PMID:41824217 | DOI:10.1007/s40122-026-00825-y