Inclusion Criteria:  Adult patients scheduled for Video-assisted thoracic surgery (VATS) lobectomy  Exclusion Criteria:  Patients who will not sign the informed consent Obesity (BMI > 35 kg/m2) Cardiovascular disease (heart failure, arrhythmia) OSAS requiring or not C-PAP therapy Chronic alcoholism intraoperative blod loss> 1500 ml One-lung ventilation duration< 60 min