Previous Abstract | Next Abstract
Printable Version
October 22, 2017
43030.645833 - 43030.729167
Room Exhibit Hall B2 - Area C
Evaluation of Anterior Neck Soft Tissue Thickness at Two Different Levels by Utrasonography for Prediction of Difficult Laryngoscopy in Obese Patients
Rohan Sharma, M.D., Neelam Prasad, M.D., Munisha Agarwal, M.D., Aakanksha Sehgal, M.D.
Maulana Azad Medical College, New Delhi, India
Disclosures: R. Sharma: None. N. Prasad: None. M. Agarwal: None. A. Sehgal: None.
Background: The incidence of difficult laryngoscopy is higher in the obese population. The usual predictors of difficult laryngoscopy have shown only mild to moderate sensitivity and specificity in its prediction. Ultrasonography of the airway has been recently shown to be an effective tool for airway assessment. Material and methods: 40 patients with a BMI ≥ 30 kg/m2 from 18 to 60 years with ASA grade 1 & 2 scheduled to undergo surgery under general anaesthesia were enrolled. The neck soft tissue was quantified using ultrasonography by measuring the distance from the skin to the vocal cords (DSVC) and the distance from the skin to the hyoid bone (DSHB). Hyomental distance (HMDS) was measured using ultrasonography and hyomental distance ratio(HMDR) was calculated. Thyromental distance, mallampatti grading, Wilson score, BMI and neck circumference were also measured as a predictor of difficult intubation. The view of the glottis at laryngoscopy was recorded as grade I - IV as per the Cormack and Lehane classification. Result: Out of 40 patients, 8 (20%) had difficult laryngoscopy (CL gd. III & IV) . Patients with difficult laryngoscopy had lesser soft tissue thickness at the vocal cords (DSVC) at 7.1±1.8mm vs 8.6±2.1mm; p=0.042 and at the level of the hyoid bone (DSHB) 1.07± 0.11 vs 1.11±0.2mm; p=0.278 as compared to the easy laryngoscopy group(CL gd I-II). The hyomental distance (HMDS) was also lesser in the difficult laryngoscopy group at 4.76±0.21 cm vs 5.09± 0.65mm; p=0.083. The hyomental distance ratio (HMDR) was 1.08±0.04 for the difficult laryngoscopy group and 1.12±0.08 for the easy laryngoscopy group, p value being 0.085. Conclusion: Ultrasonographic measurements of soft tissue thickness at vocal cords, hyoid bone, the hyomental distance and the hyomental distance ratio was lesser in the difficult laryngoscopy group as compared to the easy laryngoscopy group with the distance at the vocal cords being significant.

Copyright © 2017 American Society of Anesthesiologists