The use of BB for lung isolation is believed to provide a slower and a poorer quality of lung collapse (LC) than DLT. Over the years, the investigators have demonstrated an equivalent quality of lung collapse between the L-DLT and BB when two apnea periods are used at the beginning of one-lung ventilation (OLV). (Unpublished data) Further to complementary analysis, investigators have noted a significant difference in time to get complete lung collapse between left and right thoracic surgery when using the L-DLT. Time to obtain complete lung collapse (CLC) was not different when comparing BB and L-DLT in left thoracic surgery.