Effects of taVNS on Postoperative Pain in Complex Spinal Surgery (taVNS-cSSPain)

Effect of Transcutaneous Auricular Vagus Nerve Stimulation on Postoperative Pain in Patients Undergoing Complex Spinal Surgery: a Randomized Controlled Trial

Transcutaneous auricular vagus nerve stimulation (taVNS) is a non-invasive, novel neuromodulation technique. Previous studies have demonstrated its safety and efficacy in chronic pain, mental disorders, and other diseases, but evidence regarding its use in acute postoperative pain remains limited. This project aims to explore the efficacy and safety of taVNS in managing acute pain after complex spinal surgery. This is a single-center, double-blind, randomized controlled clinical trial, planning to recruit 98 patients scheduled to undergo complex spinal surgery at the Second Affiliated Hospital of Zhejiang University School of Medicine. Participants will be randomly assigned to either the experimental group (taVNS stimulation) or the control group (sham stimulation). The experimental group will receive five stimulation sessions, each lasting one hour, from one day before surgery to three days after surgery. The primary outcome was opioid consumption within 72 hours postoperatively. Secondary outcomes included the maximum, minimum, and mean NRS on postoperative days 1, 2, and 3; NRS before and after each taVNS stimulation; time to first PCIA compression and number of PCA sessions within 3 days postoperatively; Hospital Anxiety and Depression Scale (HADS), Pittsburgh Sleep Quality Index (PSQI), and Quality of Recovery Scale (QoR15) on postoperative day 3; time to first flatus, and first bowel movement; and the incidence of chronic pain, HADS, PSQI, and QoR15 at 3 months postoperatively.

Study Overview

• Status: Not yet recruiting
• Conditions: Postoperative Pain; Postoperative Pain Management; Postoperative Pain in Orthopaedics
• Intervention / Treatment: Device: transauricular auricular vagus nerve stimulation; Device: transauricular auricular vagus nerve stimulation

• Study Type: Interventional
• Enrollment (Estimated): 98
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Lina Yu, M.D; Phone Number: 8613958033387; Email: zryulina@zju.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Patients undergoing elective general anesthesia for complex spinal surgeries
2. Age ≥ 18 years
3. ASA classification I-III

Exclusion Criteria:

1. Ulceration or infection of the auricle skin
2. Bradycardia (heart rate of < 60 beats/min） or third-degree atrioventricular block
3. Implanted cardiac pacemaker or other electronic devices
4. Mental disorders or long-term use of psychotropic medications
5. Severe hepatic and renal insufficiency
6. Unable to understand the content of the scale assessment or unable to cooperate with the scale assessment
7. Pregnant or lactating women
8. Expected reoperation during hospitalization
9. Expected to be transferred to the ICU after surgery
10. Participation in other concurrent clinical trials

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: taVNS group; Paticipants in this arm will undergo a 60 minutes intervention of taVNS from one day before surgery to three days after surgery.	Device: transauricular auricular vagus nerve stimulation; Patients will receive five taVNS sessions, with each session lasting 60 minutes.; Device: transauricular auricular vagus nerve stimulation; Patients will receive five sham taVNS sessions, with each session lasting 60 minutes.
Sham Comparator: sham group; Paticipants in this arm will undergo a 60 minutes sham stimulation from one day before surgery to three days after surgery.	Device: transauricular auricular vagus nerve stimulation; Patients will receive five taVNS sessions, with each session lasting 60 minutes.; Device: transauricular auricular vagus nerve stimulation; Patients will receive five sham taVNS sessions, with each session lasting 60 minutes.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Opioid consumption within 72 hours postoperatively	Researchers will record the dosage of opioids used by participants within 72 hours after surgery and convert it into morphine equivalents.	Within 72 hours postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Length of hospital stay		up to 1 month
Pain score	Maximum, minimum, and mean NRS on postoperative days 1, 2, and 3, and NRS before and after taVNS stimulation.	within 72 hours postoperatively
Use of PCIA	Including the first compression time of PCA and times of PCA within 72 hours postoperatively	Within 72 hours postoperatively
Hospital Anxiety and Depression Scale (HADS) within 3 months postoperatively	Assessed by HADS within 3 months postoperatively	on the 3 months
Pittsburgh Sleep Quality Index (PSQI) within 3 months postoperatively	assessed by PSQI within 3 months postoperatively	on the 3 months
Quality of Recovery Scale (QoR15) within 3 months postoperatively	Assessed by QoR15 within 3 months postoperatively	on the 3 months
Incidence of chronic pain	Assessed by NRS at 3 months postoperatively	at 3 months postoperatively
Functional recovery indicators	Including time to first flatus and time to first bowel movement	up to 2 weeks
Adverse events		on the 3 months

Collaborators and Investigators

• Sponsor: Second Affiliated Hospital, School of Medicine, Zhejiang University

Study record dates

Study Major Dates

• Study Start (Estimated): December 24, 2025
• Primary Completion (Estimated): February 28, 2026
• Study Completion (Estimated): May 31, 2026

Study Registration Dates

• First Submitted: December 17, 2025
• First Submitted That Met QC Criteria: December 29, 2025
• First Posted (Actual): January 9, 2026

Study Record Updates

• Last Update Posted (Actual): January 9, 2026
• Last Update Submitted That Met QC Criteria: December 29, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain, Postoperative
• Other Study ID Numbers: 2025-1950

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No