Effectiveness of Detachment of the Breathing Circuit on the Rate of DLT Malposition After Postural Change

The goal of this clinical trial is to assess the incidence of double-lumen endobronchial tube displacement in patients undergoing thoracic surgery with a change in position, compared with double-lumen endobronchial tube malposition in chest surgery patients with a fixed breathing circuit. The study is to investigate: whether detaching the breathing circuit in patients undergoing thoracic surgery would reduce the rate of double-lumen endobronchial tube malposition, the incidence of postoperative pulmonary complications, and improve patient outcomes. Participants will be randomly divided into a disconnected breathing circuit group and a breathing circuit connected group and after entering the operating room, the intravenous access will be opened, and blood pressure, heart rate, electrocardiogram, oxygen saturation, arterial pressure, and end-expiratory carbon dioxide will be monitored. Anesthesia induction will be performed by an anesthesiologist, and then the double-lumen endobronchial tube will be inserted under laryngoscopic guidance. Will the catheter be delivered to the expected depth, the double-lumen endobronchial tube will be connected to the anesthesia machine for mechanical ventilation. Researchers will compare the malposition rate of the double-lumen endobronchial tube when the patient transitions from the supine to lateral decubitus position, the effect of single-lung ventilation, oxygen saturation at 5 and 10 minutes after single-lung ventilation, and postoperative recovery time.