PREDICTION OF DIFFICULT LARYNGOSCOPY BY ULTRASOUND GUIDED VALUATION OF ANTERIOR NECK SOFT TISSUE THICKNESS.

Background : The major responsibility of the anaesthesiologist is to provide adequate ventilation to the patient. Most vital element for this is the airway. Difficulties in optimal airway management can lead to serious adverse effects and failure can even lead to mortality. We have evaluated the feasibility of sonography as an imaging tool in identifying important airway anatomical structures on the anterior aspect of the neck and correlated the ultrasound-guided measurements of the airway parameters with the Cormack Lehane classification of the direct laryngoscopy for prediction of the difficult airway. Aim : To predict Difficult Laryngoscopy by Ultrasound guided valuation Of Anterior Neck Soft Tissue Thickness. Method : The study was a prospective observational study. For this study, n (no of cases) =100 considering power of 95% from the previous study; including patients between the age group of 18 to 65 years, ASA I to III grades, scheduled for elective surgery and requiring general anaesthesia with directlaryngoscopy and endotracheal intubation. Patient with anticipated difficult airway were excluded. Modified Mallampati score, Neck circumference at the level of the thyroid cartilage, Thyromental distance, BMI, distance from skin to hyoid bone and distance from skin to the anterior commissure of vocal cords using the USG machine followed by MCLS grade on laryngoscopy were noted. Result : With reference to ROC analysis, the optimal cut-offs of DSHB, DSAC, neck circumference and BMI measurements for the prediction of difficult Laryngoscopy is 0.81 cm, 0.92 cm, 35.75cm and 24.8 kg/m2 respectively with the area under the curves being 0.944, 0.970, 0.801 and 0.745 respectively. Similarly, the optimal cut-off value for modifiedMallampati grades for the prediction of difficult Laryngoscopy is Grade II and above with area under the curves being 0.718. We also found that with experience the required time to measure the distances using USG was reduced with experience. Conclusion : We conclude from our study that the BMI, modified Mallampati grade and neck circumference are good predictors of difficult laryngoscopy. However, USG guided measurements at the level of hyoid bone and anterior commissure of vocal cords showed a higher specificity and sensitivity for the prediction of difficult laryngoscopy

Comparative Evaluation of I-Gel with Uncuffed Endotracheal Tube for Adequacy of Ventilation in Elective Paediatric Surgeries

Background: Uncuffed endotracheal tubes (ETTs) are standard of care for airway management in children up to eight years of age. Direct Laryngoscopy and endotracheal intubation are invasive techniques which may cause hemodynamic changes and can give rise to airway complication. Supraglottic airway devices have been introduced since the past few decades for the management of airway in both adults and children. I-Gel, a second generation supraglottic airway device, is used frequently for securing airway for children. Methods: Total of 90 children of age 2-8 years of age were randomized into two groups, 45 children were ventilated with I-Gel and remaining 45 were ventilated with an uncuffed ETT. Ventilatory parameters like oropharyngeal leak, peak airway pressure and airway sealing quality (ASQ) score were monitored intraoperatively and possible complications were observed at a timely interval after removal of device. Results: Mean oropharyngeal leak pressure in the I-Gel and uncuffed ETT group observed were 20 cmH2O and 19.56 cmH2O respectively. ASQ score was comparable in both groups. Ten patients in the I-Gel group while two in the uncuffed ETT group had blood staining of the device after removal and the difference was statistically significant. Incidence of cough and sore throat post-extubation and after six hours was significantly higher in the ETT group as compared to the I-Gel group. Conclusion: Both devices were comparable and equally effective for adequacy of ventilation while blood staining of the device was observed in the I-Gel group however, cough and sore throat were observed in the ETT group