Inclusion Criteria:  Patients' age ≥70 years; Underwent elective non-cardiac surgery (including Orthopedics, thoracic, urology, general surgery patients)under general anesthesia ;  Exclusion Criteria:  History of neuropsychiatric diseases including delirium, mental disorders, Parkinson, dementia, etc.; The operation was cancelled due to various reasons after the patient was enrolled; severe liver disease; severe renal dysfunction defined as either having creatinine clearance < 30 ml/min or being dialysis-dependent; Patients who undergo second operation in a short period; Past 30-day prescribed use of sedative-hypnotics for the indication of insomnia; History of alcohol abuse or a history of drug dependence; Cannot with the completion of tests of cognitive function; Known allergy to skin patch; Treatment site has active skin lesion or inflammation; Refused to participate in the study.