Video-guided Versus Conventional Right-sided Double-Lumen Tubes for One-Lung Ventilation in Thoracoscopic Surgery

Right-sided double-lumen tubes are used to achieve lung isolation and one-lung ventilation during thoracoscopic surgery. Accurate positioning is particularly important because of the short right main bronchus and the need to maintain patency of the right upper-lobe bronchial opening. Malposition or displacement of a right-sided double-lumen tube may impair right upper-lobe ventilation, compromise lung isolation, and require repeated tube repositioning or fibreoptic bronchoscopy.

This prospective, multicentre, parallel-group randomised controlled trial will enrol 566 adult participants undergoing elective thoracoscopic surgery requiring one-lung ventilation with a right-sided double-lumen tube. Participants will be randomly allocated in a 1:1 ratio to either a video-guided right-sided double-lumen tube or a conventional right-sided double-lumen tube.

In the video-guided group, an integrated visualisation system provides continuous airway visual feedback during initial tube positioning and intraoperative monitoring, allowing real-time identification of changes in tube position. In the conventional group, initial tube placement is performed using standard clinical techniques and anatomical landmarks.

After initial positioning, final tube position will be confirmed by fibreoptic bronchoscopy in both groups. Subsequent fibreoptic bronchoscopy during one-lung ventilation will be performed only when clinically indicated or according to predefined rescue criteria.

The primary outcome is successful initial right-sided double-lumen tube placement, defined as placement of the assigned tube on the first intubation attempt with satisfactory final tube position and satisfactory lung isolation, without withdrawal and reinsertion or exchange to another airway device before initiation of one-lung ventilation.

Secondary outcomes include the incidence of right upper-lobe bronchial obstruction confirmed by fibreoptic bronchoscopy; incidence of intraoperative double-lumen tube displacement; incidence of hypoxemia during one-lung ventilation; requirement for rescue fibreoptic bronchoscopy; time to satisfactory right-sided double-lumen tube positioning; quality of operative lung collapse assessed by the operating surgeon; and the number of intraoperative tube repositioning events.

Participants and outcome assessors will remain blinded to treatment allocation. Because the video-guided and conventional right-sided double-lumen tubes have distinct visual and operational characteristics, the anaesthesiologist performing tracheal intubation and other intraoperative personnel directly involved in airway management cannot be blinded. Outcome assessment will be performed by personnel who are not involved in the airway intervention and remain unaware of treatment allocation.

The trial is designed to determine whether continuous airway visualisation improves initial placement success, maintains more stable right-sided double-lumen tube positioning, reduces the need for subsequent airway interventions, and improves clinically relevant conditions during one-lung ventilation.

**Inclusion Criteria:**

• Adults aged 18 years or older.
• American Society of Anesthesiologists physical status I-III.
• Scheduled for elective thoracoscopic surgery requiring one-lung ventilation with a right-sided double-lumen tube.
• Able to provide written informed consent.

**Exclusion Criteria:**

• Contraindication to placement of a right-sided double-lumen tube, including a lesion involving the right main bronchus that precludes its use.
• Known tracheobronchial anatomical abnormality that may interfere with right-sided double-lumen tube placement or lung isolation.
• Known or anticipated difficult airway.
• Requirement for rapid-sequence induction.
• Emergency surgery.
• Severe respiratory instability that, in the investigator's judgement, makes participation unsafe.
• Concurrent participation in another interventional clinical trial that could interfere with the present study.