Feasibility Study of Peripheral Venous Cannulation Pain in Predicting Acute Pain After Total Knee Arthroplasty

Inclusion Criteria: 1. Patients undergoing the first unilateral total knee arthroplasty surgery under general anesthesia combined with nerve block ; 2. Age : 18 years old ≤ age ≤ 80 years old ; 3. ASA grade I-II ; 4. Informed consent was signed by patients or immediate family members before operation. Exclusion Criteria: 1. There are known pain abnormalities, mental disorders, cognitive dysfunction ; 2. patients with long-term use of opioids and a history of drug dependence ; 3. patients with alcohol dependence ; 4. the patient refused to use the analgesic pump ; 5. Difficult to understand the VAS score ; 6. body mass index ≥ 40 ; 7. hand nerve abnormalities, hand loss ; 8. plan postoperative ICU patients ; 9. In other cases, the researchers believe that is not suitable for this researcher.