ABSTRACT
Objective · To evaluate the value of ultrasonic measurement of distance from skin to epiglottis (DSE) for predicting the difficult airway. Methods · 71 patients (20-80 year-old, ASA Ⅰ-Ⅲ ) undergoing endotracheal intubation and general anesthesia for an elective surgical procedure were enrolled. Conventional airway evaluation was performed. The distance from skin at thyroid cartilage upper edge to epiglottis was measured using ultrasound before anesthesia and compared between patients with difficult airway and normal airway. The effects of different methods for evaluating difficult airway were analyzed Results · The ultrasonic measurements of DSE on parasagittal view in patients with difficult airway and normal airway were (23.31±0.43) mm and (19.21±0.27) mm, respectively. The difference was statistically significant (P=0.003). The area under the ROC curve of ultrasonic measurement was 0.799 (95% CI:0.639-0.958) with the best cutoff point of 23.6 mm. The specificity of ultrasonic measurement was significantly increased as compared with Mallampati classification (96.43% vs 71.40%, P=0.004). The difference in sensitivity was not statistically significant (60.00% vs 73.33%, P=0.170). Conclusion · Ultrasonic measurement of DSE on parasagittal view can be used to predict the difficult airway.