Pleuropulmonary Ultrasound With Clinical Examination to Check the Good Position of the Double Lumen Tube Intubation

Using a new ultrasound approach, allow us to avoid the systematic use of bronchoscopy which is an invasive procedure. Although rare, several complications are known with, among other things, the occurrence of pulmonary infections, pneumothorax associated with increased pressure in the airways, atelectasis or bronchospasm. Avoid the systematic control by fibroscopy in simple cases which makes it possible to overcome the complications related to its use and its cost. The investigators want to evaluate the diagnostic value of the echographic strategy in 2 steps (2D and TM) on 3 sections (pulmonary field on the axillary line of the 2 sides and left upper lobe) associated with the clinical examination in preoperative by comparing with the gold standard: fibroscopy. Clinical examination and pleuropulmonary ultrasound should have a positive predictive value of at least 85%.