Impact of Different Lung Isolation Devices on Pharyngolaryngeal Injuries After Pulmonary Resection

Background: Video-assisted thoracoscopic surgery (VATS) necessitates effective lung isolation techniques. While double-lumen endotracheal tubes (DLT) remain the gold standard, they are associated with significant airway trauma and postoperative laryngopharyngeal morbidity. Laryngeal mask airway (LMA) combined with bronchial blockers represents a promising alternative; however, conventional bronchial blockers pose limitations including challenging positioning and potential airway injury. Novel visual bronchial blocker technology offers enhanced positioning accuracy and reduced airway manipulation, potentially minimizing laryngopharyngeal injury while maintaining effective lung isolation.

Objective: To compare the efficacy and safety of LMA combined with a visual bronchial blocker versus DLT for lung isolation in VATS, with a primary focus on reducing postoperative laryngopharyngeal injury.

Methods: This prospective, randomized, controlled, single-blind, multicenter clinical trial will enroll 270 patients scheduled for elective VATS anatomical lung resection. Participants will be randomly allocated (1:1 ratio) to either the visual bronchial blocker group (VBB group, n=135) or the DLT group (n=135) across three major thoracic surgery centers. The primary outcome is the incidence of laryngopharyngeal injury (sore throat and/or hoarseness) at 24 hours postoperatively. Secondary outcomes include laryngopharyngeal injury at 1 hour and 48 hours postoperatively, intraoperative device dislodgement, hypoxemia (SpO₂ < 90%), quality of lung collapse, airway instrumentation time, hemodynamic fluctuations, emergence quality, device-related complications, and hospital length of stay. Statistical analysis will be performed using SPSS 24.0, employing appropriate parametric and non-parametric tests.

Inclusion criteria

• Age ≥18 years
• Scheduled for elective VATS pulmonary resection under general anesthesia
• American Society of Anesthesiologists (ASA) physical status I-III
• Body mass index (BMI) 18.5-30.0 kg/m²
• Written informed consent

Exclusion criteria

• Anticipated difficult airway (Mallampati class IV, previous difficult intubation, airway abnormalities)
• Gastroesophageal reflux disease or gastric retention
• Active pulmonary infection or bleeding
• Severe pulmonary dysfunction (FEV1 <50% predicted)
• Previous lung surgery or bilateral lung surgery
• Cognitive impairment affecting outcome assessment
• Chronic throat pain or voice abnormalities within 24 hours preoperatively
• Abnormal right upper lobe bronchial anatomy on preoperative CT for right-sided procedures
• Any condition deemed unsuitable for study participation by anesthesiologist or surgeon