Effectiveness of Lung Sono in One-lung Ventilation

"The patient undergoing thoracic surgery is intubated with double lumen tube after induction of general anesthesia with propofol and remifentanil.~In the intervention group, alveolar recruitment is performed to the non-surgical side of lung under examination with ultrasound just after anesthesia induction.~During the gradual increment in the pressure of recruitment, the anesthesiologist can find the opening pressure that means the minimal pressure at which observed atelectasis starts to disappear.~Then, alveolar recruitment is performed with the opening pressure until the atelectasis is not visible."