The purpose of this study was to determine whether disconnecting pulmonary vagus nerve branch can abatement chronic cough in patients undergoing unilateral thoracoscopic lobectomy,compared with preserving pulmonary vagus nerve branch.

After screening for the Inclusion criteria and the exclusion criteria, 116 patients undergoing unilateral thoracoscopic lobectomy are randomly assigned to two groups, disconnecting pulmonary vague nerve branches and preserving pulmonary vague nerve branches. The incidence of chronic cough after surgery is compared between groups.

Inclusion Criteria:

• Patients with preoperative imaging of bronchial lung cancer below the secondary bronchus ,the maximum diameter of the tumor ≤ 5cm (T ≤ 2) and staging check not suggesting distant and mediastinal lymph node metastasis (N ≤ 1, M = 0) schedule to receive elective unilateral thoracoscopic lobectomy from 2019 to 2021 will be included in the trial.
• ASAⅠ-Ⅲ

Exclusion Criteria:

• Chronic cough (>8 weeks), its causes including chronic bronchitis, asthma, gastroesophageal reflux disease, history of postnasal drip syndrome, and the use of ACEI drugs and so on;
• other history of lung surgery;
• patients with severe arrhythmia;
• there are contraindications for anesthesia and surgery;
• pregnancy and lactation.