Abstract No.: ABS2511: Ultrasound assessment of airway parameters and their clinical correlation to predict difficult airway and laryngoscopy.

Abstract

Background&Aims:Increased tongue thickness, pre-epiglottic depth and anterior-neck soft tissue thickness are likely to be associated with difficultairways. This study was aimed to find out various ultrasound airway assessment measurements and their efficacy and correlation with difficult airway and laryngoscopy.Methods:A prospective hospital based observational study was conducted at KLEA’s Dr.Prabhakar Kore Hospital and MRC, KAHER, Belagavi, after attaining institutional ethical committee clearance, in 60 adult American Society of Anesthesiologists (ASA)I/II patients undergoing tracheal intubationunder general anaesthesia. Patients with head andneck or cervical spine pathology were excluded. Ultrasonographic assessmentof tongue thickness, ratio of Pre-E/E-VC and anterior neck soft tissue thickness at level of vocal cords weredone with patients in supine position, before induction of anaesthesia. These were compared with Cormack-Lehane grading assessed during laryngoscopy and intubation. These assessments were conducted to investigate the potential predictive value of their combination for difficult laryngoscopy.Results:Using Pearson’s correlation, tongue thickness was found to be highly significant in correlation with the Cormack-Lehanegrading along with ratio of Pre-E/E-VC thus to predict difficult laryngoscopy with a significant p value of <0.0001. Thesensitivity of Pre-E/E-VC ratio was found to be 91.67% with a diagnosing accuracy of around 82%. Conclusion:The ultrasound parameters have greater sensitivity and specificity than conventional airway tests. The maximum vertical tongue thickness and ratio of pre-epiglottic space to distance from epiglottis to midpoint-of-vocalcords have better prediction for difficult laryngoscopy.