It is controversial as to which ventilation mode is better in one-lung ventilation(OLV), volume controlled ventilation(VCV) or pressure controlled ventilation(PCV). This study was designed to figure out if there was any difference between these two modes on oxygenation and postoperative complications under the condition of protective ventilation(PV).

This is a single center, single blinded prospective study on two different ventilation mode during one lung ventilation for patients under video assistant thoracoscopy(VATS) lobectomy. After institutional approval and written informed consent were obtained, 60 patients with primary lung cancer under VATS lobectomy in Zhongshan Hospital Fudan University were enrolled and randomized into two groups:VCV group(group V) or PCV group(group P).

Inclusion criteria were age between 18-75 years , ASA I-II, lateral decubitus position with at least 1h OLV and preoperative FEV1>50% predicted. Preoperative exclusion criteria were previous lobectomy , COPD , asthma, uncompensated cardiac disease or contraindications for epidural catheter. Intraoperative exclusion criteria were SpO2 under 90% after intratracheal suction, reconfirmation the position of double lumen tracheal tube(DLT) and recruitment maneuver of dependant lungs.

Inclusion Criteria:

• ASA I-II, lateral decubitus position with at least 1h OLV and preoperative FEV1>50% predicted

Exclusion Criteria:

• Preoperative exclusion criteria were previous lobectomy , COPD , asthma, uncompensated cardiac disease or contraindications for epidural catheter. Intraoperative exclusion criteria were SpO2 under 90% after intratracheal suction, reconfirmation the position of double lumen tracheal tube(DLT) and recruitment maneuver of dependant lungs