The patients were divided into two groups by random number method: GroupRD1 group and GroupRD2 group were given general anesthesia and intercostal nerve block.The drug for intercostal nerve block was 0.33% ropivacaine +2.333mg compound betamethasone (1.667mg betamethasone dipropionate + 0.667mg betamethasone sodium phosphate) to 15ml.

The RD1 group received ultrasound-guided intercostal nerve block at the incision before anesthesia induction, and the RD2 group received ultrasound-guided intercostal nerve block at the lateral costal Angle before anesthesia induction.

Inclusion Criteria:

1. 18-70 years old
2. ASA grade I-III
3. BMI: 18.5-28kg/m2
4. Type of surgery: elective thoracoscopic lung mass resection
5. Informed consent has been signed by the patient and/or family members

Exclusion Criteria:

1. game anesthesia or sugar cortical hormone drugs allergic
2. preoperative use of opioid medicines
3. serious blood coagulation dysfunction
4. serious heart, lung, liver and renal insufficiency
5. put, chemotherapy, and glucocorticoid immunosuppressive therapy history or diseases of the immune system
6. peptic ulcer
7. newly gastrointestinal surgery
8. has a history of thoracic surgery
9. is the central nervous system disease
10. Other glucocorticoids should be used with caution in patients such as fractures, wound repair, corneal ulcers, hyperadrenocortical disease, diabetes mellitus, pregnant women, etc.