Transcutaneous Auricular Vagus Nerve Stimulation Prevents Postoperative Delirium in Elderly Patients

This study aims to conduct a prospective, randomized controlled clinical trial on the preventive use of taVNS to improve the incidence of Postoperative Delirium(POD) in elderly patients undergoing anesthesia surgery. The intervention group will receive "standard-stimulation parameters" of taVNS（25HZ，250μs）, while the control group will receive "low-stimulation parameters" of taVNS(1HZ,250μs). The main outcome measure of the study was the incidence of POD within 5 days after surgery. Secondary outcome measures include incidence of new mild and severe postoperative neurocognitive impairment during hospitalization and 90 days, all-cause mortality rate at 90 days, incidence of related adverse events, and length of stay.

Inclusion criteria

• Age≥65 years
• Expected operation time≥ 2 hours
• Postoperative hospital stay≥ 4 days
• Sign the informed consent form

Exclusion criteria

• Neurosurgery or cardiac surgery
• Emergency surgery within 6 hours of admission
• End-stage disease with an expected survival of < 3 months
• Preoperative severe cognitive dysfunction affected perioperative cognitive function assessment
• Severe sinus bradycardia, AVB of degree II and above, pacemaker placement