Preoperative ultrasonographic measurements of tongue thickness, tongue thickness-thyromental distance ratio and skin to epiglottis distance in predicting unanticipated difficult airway. A prospective comparative observational study.

This is a prospective observational study conducted from August 2025 to February 15 2026 in a tertiary care teaching hospital, involving 60 patients undergoing elective surgeries under general anesthesia requiring endotracheal intubation. The study aims to assess the correlation between preoperative upper airway ultrasound measurements and the difficulty of laryngoscopy. Preoperative evaluation includes airway examination (such as thyromental distance), administration of pantoprazole, and ultrasound assessment using curvilinear and linear probes to measure tongue thickness (TT) and distance from skin to epiglottis (DSE). During surgery, direct laryngoscopy will be performed, and the Cormack-Lehane (CL) grade will be documented without external laryngeal manipulation. Laryngoscopy is classified as easy (CL I, II) or difficult (CL III, IV), and the need for adjuncts like bougie or stylet will also be noted. The study aims to identify ultrasound-based predictors of difficult airway management.