The Effect of Transcutaneous Electrical Acupoint Stimulation Combined With Transcutaneous Auricular Vagus Nerve Stimulation on Postoperative Delirium in Elderly Patients Undergoing Gastrointestinal Surgery

Inclusion Criteria: 1. Aged ≥65 years; 2. Body mass index (BMI) 18-30 kg/m²; 3. American Society of Anesthesiologists (ASA) physical status classification I-III; 4. Patients scheduled for elective laparoscopic gastrointestinal surgery; 5. Willingness to provide written informed consent and comply with the treatment regimen; 6. Absence of severe organic diseases, psychiatric disorders, or preoperative delirium. Exclusion Criteria: 1. Preoperative Mini-Mental State Examination (MMSE) score \<20; 2. Electrocardiographic evidence of severe bradycardia (heart rate \<50 beats per minute); 3. Presence of skin lesions or infections at the electrical stimulation site; 4. History of preoperative chemotherapy or radiotherapy; 5. Concomitant severe organic diseases with compromised tolerance to interventions; 6. Prior exposure to Transcutaneous Electrical Acupoint Stimulation (TEAS) or transcutaneous auricular vagus nerve stimulation (taVNS) with documented insensitivity; 7. Inability to communicate normally, dementia, hearing impairment, or severe psychiatric disorders.