Diagnostic value of ultrasound for predicting the occurrence of airway difficulty in patients undergoing anesthesia.

Objective: To investigate the diagnostic value of ultrasound for predicting occurrence of airway difficulty in patients undergoing anesthesia.

Methods: A total of 273 patients airway difficultyundergoing general anesthesia admitted to the Department of Anesthesiology, Nanjing First Hospital, Affiliated to Nanjing Medical University from January 2017 to October 2021 were selected in this prospective study. Among them, 73 suffered airway difficulty and the airway difficultyremaining 200 did not. Factors relating to the occurrence of difficulty were observed, and the hyomental distance ratio [HMDR = hyomental distance at the extreme of head extension (HMDe)/hyomental distance in the neutral position (HMDn)] combined with the distance from skin to epiglottis midway (DSEM) were further studied for the prediction of airway difficulty occurrence.

Results: Multivariate regression analysis revealed that HMDe, HMDR, and DSEM were factors associated with the occurrence of difficulty (all P<0.05). The specificity and the sensitivity of HMDR in diagnosing airway difficulty were 0.715 and 0.918 respectively at a cutoff value of 1.245 mm. The specificity and sensitivity of DSEM in diagnosing airway difficulty were 0.959 and 0.767 respectively at a cutoff value of 22.952 nm. When HMDR was combined with DSEM, the specificity of the diagnosis of airway difficulty was 0.973, and the sensitivity was 0.904.

Conclusion: HMDe, HMDR and DSEM can be used to predict occurrence of airway difficultyand HMDR combined with DSEM has value in the diagnosis.