Title: Ultrasound Guided Preoperative Airway Assessment and Its Correlation with Standard Clinical Airway Assessment in Patients Having BMI >23KG/M2
Authors: Dr Kanika Sharma, Dr Kartik Syal, Dr Rajesh Verma, Dr Surinder Singh
DOI: https://dx.doi.org/10.18535/jmscr/v8i6.51
Abstract
Introduction
Successful airway management requires a range of knowledge and skills to predict difficulty and to formulate an airway management plan as well as to have the skills necessary to execute the plan using the wide array of airway devices available. Difficult laryngoscopy and tracheal intubation rate still remains at 1.5–13% due to poor reliability of traditional protocols, algorithms and combinations of screening tools in identifying a potentially difficult airway.1 Various studies had shown that the incidence of difficult bag and mask ventilation in overweight patients is approximately 6% whereas in lean patients is approximately 1% and incidence of difficult intubation in overweight is 1.5-16% and in lean it is approximately 7%.2
Clinical criterias routinely used to assess patients prior to anesthesia have variations according to patient’s height, weight and ethnicity.
Ultrasonography (USG) is well-known as a fast, safe and noninvasive technique. There were very limited studies which showed value of USG derived parameters in assessing airway in obese patients and its co-relation with proven clinical parameters. The clinical parameters (MPS, TMD, neck circumference) which were included in the present study are the proven ones to assess airway, especially in overweight and obese patients. The USG derived parameters, preepiglotic space depth (PES), epiglottis to vocal cord distance (EVC), skin to dorsum of tongue distance (S-DT) are the USG parameters taken and clinically assessed parameters and USG parameters were co-related with each other taking Cormacke-Lehane grading as a reference point.
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