1. Newly diagnosed or existing COPD defined by GOLD, and FEV1 of\<80% predicted and FEV1/FVC\<70%
2. Diagnosed as primary lung cancer by China guidelines on diagnosis and treatment of primary lung cancer
3. .Consistent with indication of operation of pulmonary single lobectomy surgery by China guidelines on diagnosis and treatment of primary lung cancer
4. General anesthesia and double cavity intubation was used during operation
5. ASA Classification of Anesthesia Risk is in category 1-3 both in baseline
6. age from 40-80 years old
7. Smoking cessation more than two weeks before operation
8. SP O2\>90% before surgery
9. Hemoglobin \> 10g/dl
10. Estimated duration of surgery \< 4 hours
11. 18.5\<BMI \< 28
You may not be if
1. Patients who had taken systemic corticosteroids in the preceding 1month before baseline
2. Patients who had pneumonia in the preceding 1month before baseline
3. Patients with a history of recent myocardial infarction, heart failure, tuberculosis
4. Subject with known or suspected human immunodeficiency virus infection
