Effect of Transcutaneous Auricular Vagus Nerve Stimulation on Postoperative Opioid Consumption in Patients Undergoing Major Abdominal Surgery

Effect of Transcutaneous Auricular Vagus Nerve Stimulation on Postoperative Opioid Consumption in Patients Undergoing Major Abdominal Surgery

This study aims to design a prospective, double-blind, randomized controlled trial to compare the effects of transcutaneous auricular vagus nerve stimulation (taVNS) on postoperative visceral pain in patients undergoing major abdominal surgery. Participants will be randomly assigned to receive either taVNS or sham stimulation. The total consumption of opioids and other analgesics within 24 hours post-surgery in the AICU will be recorded, along with follow-up assessments of pain scores and quality of recovery scores (Qor-15) at 24 hours postoperatively.

Inclusion Criteria:

• Age between 18 and 85 years, regardless of gender
• ASA physical status classification I-III
• Scheduled for elective major abdominal surgery under general anesthesia, with postoperative admission to the AICU for monitoring
• Anticipated duration of stay in the AICU is approximately 24 hours

Exclusion Criteria:

• History of vagus nerve-related diseases (such as vasovagal syncope);
• Severe arrhythmias or implanted electronic devices such as pacemakers;
• Skin lesions, infections, or deformities at the site of external ear stimulation;
• Long-term preoperative use of opioid medications or sedatives;
• Allergy to study-related medications;