Transcutaneous Auricular Vagus Nerve Stimulation for Preventing Acute Kidney Injury in Patients Undergoing Cardiac Surgery With Cardiopulmonary Bypass

NCT07549243 | Not Yet Recruiting

• 1 other identifier: 20260315122240876
• Study Type: interventional
• Target: 152
• Locations: 0 countries
• Sites: N/A

Brief Summary

Acute kidney injury (AKI) is a common complication after cardiac surgery using cardiopulmonary bypass, leading to longer hospital stays and worse outcomes. Effective preventive therapies are lacking. This randomized controlled trial investigates whether transcutaneous auricular vagus nerve stimulation (taVNS)-a non-invasive ear stimulation technique-can reduce AKI after cardiac surgery. A total of 152 patients undergoing elective cardiac surgery with cardiopulmonary bypass will be randomly assigned to receive either taVNS or sham stimulation. The intervention begins before surgery and continues daily through postoperative day 5. The primary outcome is the incidence of AKI within 7 days after surgery. Secondary outcomes include AKI severity, need for dialysis, kidney function recovery, complications, and inflammatory biomarkers. This study is approved by the institutional ethics committee. All participants will provide written informed consent.

Conditions

Acute Kidney Injury; Cardiac Surgery; Cardiopulmonary Bypass

Outcome Measures

Primary Outcomes (1)

• Incidence of Acute Kidney Injury (AKI) Within 7 Days After Surgery

  Within 7 days after surgery

Secondary Outcomes (33)

• Severity of Acute Kidney Injury (AKI) by KDIGO Stage

  Within 7 days after surgery

• Requirement of Renal Replacement Therapy (RRT)

  From surgery to hospital discharge, assessed daily, up to 90 days

• Duration of RRT

  From initiation to discontinuation of RRT, assessed daily, up to 90 days

• Persistent AKI at Postoperative Day 7

  Postoperative day 7

• Time to Kidney Function Recovery Among Participants With AKI

  From AKI diagnosis to recovery, assessed daily, up to 30 days after surgery

Study Arms (2)

Transcutaneous Auricular Vagus Nerve Stimulation (taVNS)

EXPERIMENTAL

Device: Transcutaneous Auricular Vagus Nerve Stimulation

Sham Stimulation

SHAM COMPARATOR

Device: Sham Stimulation

Interventions

Transcutaneous Auricular Vagus Nerve Stimulation DEVICE

Participants in this arm receive active transcutaneous auricular vagus nerve stimulation (ta-VNS) using the tVNS501 device. Stimulation is delivered to the left cymba conchae (auricular branch of the vagus nerve) with the following parameters: frequency 25 Hz, pulse width 250 µs, 30 seconds on / 30 seconds off cycling. Intensity is adjusted starting from 0.4 V and increased in 0.4 V increments until the participant perceives mild discomfort, then reduced to the highest tolerable non-painful level. The intervention begins on the day of surgery (from the preoperative holding area through 6 hours postoperatively in the ICU) and continues on postoperative days 1 through 5 with two 120-minute sessions per day (at 9:00 and 14:00). The device is applied by trained non-blinded operators.

Transcutaneous Auricular Vagus Nerve Stimulation (taVNS)

Sham Stimulation DEVICE

Participants in this arm receive sham stimulation using the same tVNS501 device. Electrodes are placed on the left cymba conchae following the same procedure as the active group, but no electrical current is delivered. The stimulation settings are displayed on the device to maintain blinding, but the output is turned off. The schedule and duration of device application are identical to those in the active stimulation group.

Sham Stimulation

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age ≥18 years
• Scheduled for elective cardiac surgery with cardiopulmonary bypass under general anesthesia
• Baseline estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m² (CKD-EPI formula)
• American Society of Anesthesiologists (ASA) physical status classification I-III
• New York Heart Association (NYHA) functional classification I-III
• Able to understand and cooperate with study procedures
• Willing to participate and provide written informed consent. For participants unable to read or sign due to incapacity or illiteracy, consent may be obtained from a legally authorized representative or witnessed by an impartial third party as per ethical guidelines

You may not qualify if:

• Solitary kidney, history of kidney transplantation, pre-existing renal replacement therapy, or pre-existing acute kidney injury (KDIGO criteria)
• Contraindications to transcutaneous auricular vagus nerve stimulation, including active infection, dermatitis, skin breakdown, or severe psoriasis in the bilateral auricular region; allergy to silicone, electrode gel, or device materials; uncontrolled arrhythmia, symptomatic bradycardia, sick sinus syndrome, second- or third-degree atrioventricular block, implanted pacemaker or defibrillator; carotid sinus hypersensitivity; uncontrolled epilepsy; or active peptic ulcer disease
• Received vagus nerve stimulation, auricular acupuncture, or transcutaneous electrical nerve stimulation within 1 month prior to enrollment
• Long-term use of medications that significantly affect autonomic nervous system tone or renal blood flow and cannot be safely paused before surgery
• Active systemic infection or sepsis (Sepsis-3 criteria) prior to surgery
• Acute ischemic or hemorrhagic stroke, or acute myocardial infarction within 3 months prior to enrollment
• Severe hepatic dysfunction (Child-Pugh Class C), acute liver failure, or other serious life-threatening conditions
• Vulnerable populations (excluding elderly or illiterate individuals) including critically ill patients, individuals with psychiatric disorders, cognitive impairment, or pregnant women
• Any other condition deemed by the investigator to make the participant unsuitable for study participation

Sponsors & Collaborators

• Sir Run Run Shaw Hospital: lead

MeSH Terms

Conditions

Acute Kidney Injury

Condition Hierarchy (Ancestors)

Renal Insufficiency; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Male Urogenital Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: April 6, 2026
• First Posted: April 24, 2026
• Study Start: April 15, 2026
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): May 1, 2027
• Last Updated: April 24, 2026

Record last verified: 2026-04