Postoperative laryngopharyngeal discomfort after extubation can lead to severe throat pain, dysphagia, or postoperative tongue oedema. Possible mechanisms include increased oral pressure, obstruction of venous and lymphatic return in the neck, and increased capillary hydrostatic pressure, which leads to oedema of the tongue and upper airway. However, real-time monitoring indicators of anaesthesia are lacking. Therefore, we designed this study to accurately measure the contact force of the tracheal tube on the tongue in different surgical positions during general anaesthesia.

This prospective single-centre observational study will enrol 54 patients undergoing elective surgery under general anaesthesia for>2 hours with endotracheal tube application from 1 July 2023 to 30 June 2024. Patients will be divided into the supine (Supine group) and high-risk (Flexion group) groups. Dynamic changes in the contact force between the tracheal tube and tongue will be measured using T-Scan technology. All patients will be followed up for 7 days postoperatively. The primary endpoint is postoperative laryngopharyngeal discomfort. Secondary outcomes include the time to the first successful recovery of oral intake of fluids and solid food, and airway-related events.

Ethical approval was obtained from the Ethics Committee of Clinical Research of China-Japan Friendship Hospital (2023-KY-219, approved on 14 September 2023). Informed consent will be obtained during anaesthesia evaluation. This study aims to explore the characteristics of the contact force on the tongue caused by endotracheal intubation in different surgical positions and to provide a better understanding of the risk factors and prevention of postoperative laryngopharyngeal discomfort. The findings of this study will be presented at our hospital, reported on ClinicalTrials.gov, and published in peer-reviewed journals.

NCT05987293.