Effect of taVNS on Perioperative Anxiety in Major Abdominal Surgery (taVNS-MASAnx)

Effect of Transcutaneous Auricular Vagus Nerve Stimulation on Perioperative Anxiety in Patients Undergoing Major Abdominal Surgery

It is reported that over 50% of patients undergoing major abdominal surgery experience perioperative anxiety, which often triggers a vicious cycle of "anxiety-pain-gastrointestinal dysfunction" and significantly hinders postoperative recovery. Existing pharmacological and psychological interventions are limited by adverse effects such as respiratory depression, paralytic ileus, and poor patient compliance. While transcutaneous auricular vagus nerve stimulation (taVNS) has shown promise as a non-invasive neuromodulation technique for chronic neuropsychiatric disorders, high-quality evidence regarding its application in anxiety-susceptible perioperative populations is still lacking. This multicenter, randomized, parallel-group, double-blind, sham-controlled trial aims to recruit 282 patients undergoing elective major abdominal surgery across four centers in Mainland China. Eligible participants will be randomized (1:1) to receive either taVNS or sham stimulation for 60 minutes daily from two days prior to surgery through the day of the operation. The primary outcome is the incidence of perioperative anxiety from the day of surgery to 72 hours postoperatively, while secondary outcomes include depression, sleep quality, pain intensity, postoperative delirium, frailty scores, quality of recovery, time to first flatus and defecation, and length of hospital stay.

Study Overview

• Status: Not yet recruiting
• Conditions: Major Abdominal Surgery; Perioperative Anxiety
• Intervention / Treatment: Device: transauricular auricular vagus nerve stimulation; Device: transauricular auricular vagus nerve stimulation

• Study Type: Interventional
• Enrollment (Estimated): 282
• Phase: Not Applicable

Contacts and Locations

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

Study Locations

• China
  • Hangzhou, China
    • The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.
    • Contact: Lina Yu; Phone Number: +86-13958033387; Email: zryulina@zju.edu.cn
  • Zhejiang
    • Huzhou, Zhejiang, China
      • Huzhou Central Hospital
    • Jiaxing, Zhejiang, China
      • The Second Affiliated Hospital of Jiaxing University
      • Contact: Hongmei Zhou; Phone Number: +86-13867300139; Email: drhongmeizhou@163.com
    • Meicheng, Zhejiang, China
      • Jiande First People's Hospital
      • Contact: Sanyue Wang; Phone Number: +86-13968126731; Email: 1501556348@qq.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Age: Between 18 and 85 years.
2. Patients undergoing elective major abdominal surgery under general anesthesia, with an anticipated operative duration of ≥ 2 hours and a predicted postoperative length of stay of ≥ 2 days.
3. ASA classification I-III.

Exclusion Criteria:

1. Active skin breakdown, erythema, swelling, infection of the ear, or significant anatomical abnormalities of the external ear.
2. Pre-existing bradycardia (resting heart rate < 50 beats/min) or third-degree atrioventricular block.
3. Presence of a cardiac pacemaker or other active electronic implants.
4. A documented history of traumatic brain injury within the past 6 months.
5. Chronic pain or long-term reliance on analgesic medications.
6. Severe neuropsychiatric disorders or chronic use of psychotropic medications, including corticosteroids, antidepressants, or anxiolytics.
7. Severe cognitive impairment or any condition precluding effective communication or completion of the assessment scales.
8. Women who were pregnant, lactating, or planning to conceive.
9. Current enrollment in other interventional clinical trials.
10. Anticipated direct transfer to the ICU immediately following surgery.

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; Participants in the taVNS group will receive 60-minute stimulation sessions daily, starting from two days preoperatively and continuing through the day of surgery, for a total of three sessions.	Device: transauricular auricular vagus nerve stimulation; Patients will receive three taVNS sessions, with each session lasting 60 minutes.; Device: transauricular auricular vagus nerve stimulation; Patients will receive three sham taVNS sessions, with each session lasting 60 minutes.
Sham Comparator: sham group; Participants in the sham group will receive 60-minute sham stimulation sessions daily, starting from two days preoperatively and continuing through the day of surgery, for a total of three sessions.	Device: transauricular auricular vagus nerve stimulation; Patients will receive three taVNS sessions, with each session lasting 60 minutes.; Device: transauricular auricular vagus nerve stimulation; Patients will receive three sham taVNS sessions, with each session lasting 60 minutes.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of perioperative anxiety	Incidence of perioperative anxiety from the day of surgery through 72 hours postoperatively, as assessed by the 14-item Hamilton Anxiety Rating Scale (HAMA-14).	From the day of surgery through 72 hours postoperatively following the completion of the intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Length of hospital stay	Length of hospital stay	up to 1 month
Severity and scores of perioperative anxiety	Perioperative anxiety severity and scores will be evaluated at the following timepoints: pre- and post-intervention (T0-T5); 2 hours post-surgery (T6); postoperative days 1, 2, 3, and 7 (T7-T10); and one month post-surgery (T11)	Within one month postoperatively
Severity and scores of perioperative depression	Severity and scores of perioperative depression (HAMD-24) will be evaluated at the following timepoints: pre- and post-intervention (T0-T5); 2 hours post-surgery (T6); postoperative days 1, 2, 3, and 7 (T7-T10); and one month post-surgery (T11)	Within one month postoperatively
Sleep Quality	Sleep Quality (Pittsburgh Sleep Quality Index [PSQI]) will be evaluated at the following timepoints: postoperative days 1, 3, and 7 (T7, T9, T10), and at the one-month postoperative follow-up (T11)	Within one month postoperatively
Pain intensity	Pain Intensity (Numeric Rating Scale[NRS]) will be assessed at the following timepoints: 2 hours post-surgery (T6); postoperative days 1, 2, 3, and 7 (T7-T10); and at the one-month postoperative follow-up (T11)	Within one month postoperatively
Incidence of postoperative delirium within the first 7 days after surgery	Incidence and severity of postoperative delirium (CAM-3D) will be evaluated at the following timepoints: 2 hours post-surgery (T6) and postoperative days 1, 2, 3, and 7 (T7-T10)	Within 7 days postoperatively
Frailty score	Frailty Score (The FRAIL Scale [Fatigue, Resistance, Ambulation, Illness, and Loss of Weight]) will be evaluated at the following timepoints: postoperative days 1, 3, and 7 (T7, T9, T10), and at the one-month postoperative follow-up (T11). The FRAIL scale assesses five components: Fatigue, Resistance, Ambulation, Illness, and Loss of weight	Within one month postoperatively
Quality of recovery	Quality of Recovery (Quality of Recovery Scale[QoR-15]) will be evaluated at the following timepoints: postoperative days 1, 3, and 7 (T7, T9, T10), and at the one-month postoperative follow-up (T11)	Within one month postoperatively
Opioid consumption within the first 7 postoperative days	Opioid consumption within the first 7 postoperative days	Within 7 days postoperatively
Postoperative recovery: including time to first ambulation, time to first flatus, and time to first defecation	Postoperative recovery milestones: including time to first ambulation, time to first flatus, and time to first defecation	up to 1 month

Collaborators and Investigators

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

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2026
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): February 1, 2027

Study Registration Dates

• First Submitted: March 17, 2026
• First Submitted That Met QC Criteria: March 22, 2026
• First Posted (Actual): March 27, 2026

Study Record Updates

• Last Update Posted (Actual): May 19, 2026
• Last Update Submitted That Met QC Criteria: May 15, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: 2026-0369

Drug and device information, study documents

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