Role of Ultrasonography in Airway Management

Study Overview
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Brief Summary
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Ultrasound is one of the most useful devices in daily anesthesia practice. Latest purpose of ultrasound usage is prediction of difficult intubation. In this study, we aimed to predict difficult laryngoscopy and intubation by using ultrasound measurement of neck soft tissue thickness in obese patient preoperatively.

Detailed Description
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In this prospective and randomized controlled study, mallampati scores, interincisor gap, thyromental distance, neck circumference measurement and upper lip bite test scores will be recorded in sixty obese patients. Additionally, neck tissue thickness will be recorded at 4 different levels (hyoid bone-skin distance, epiglot-skin distance , thyroid istmus-skin distance, vocal cord-skin distance) after the sniffing position by ultrasound with the linear probe. All measurements will be repeated three times and an average values will be recorded. After all this measurements, endotracheal intubation will be performed by an experienced anesthetist who is uninformed about study. During intubation the Cormack Lehane (C/L, grade 1: full view of the vocal cords; grade 2a: partial view of the glottis; 2b: posterior part of the vocal cord and arytenoids visible; grade 3: only epiglottis visible; and grade 4: neither epiglottis nor glottis visible) and the Intubation Difficulty Scale (IDS) score (the numbers of attempts, operators, and alternative techniques used, the C/L grade of laryngoscopic view, lifting force and external laryngeal manipulation required, and position of the vocal cords. Every insertion of the laryngoscope and advancement of the tracheal tube towards the glottis counted as an attempt. A score of >5 indicates moderate-to-major difficulty) will be recorded.

Official Title
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Is There a Role for Ultrasonography in the Airway Management of Patients With Obesity

Conditions
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Obese Patients

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BMI>30 18-65 YEARS ASA 1-2-3 Obese patients Exclusion Criteria: Pregnancy Upper airway pathology Cervical spine pathology Laryngeal pathology

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hyoid bone-skin distance -effect of ultrasound on prediction of difficult laryngoscopy | The hyoid bone-skin distance will be measured by using ultrasound in centimeters | 30 minutes before induction | 
| Epiglottis-skin distance | The epiglottis-skin distance will be measured by using ultrasound in centimeters | 30 minutes before induction | 
| Thyroid isthmus-skin distance | The thyroid isthmus-skin distance will be measured by using ultrasound in centimeters | 30 minutes before induction | 
| Vocal cord-skin distance | The vocal cord-skin distance will be measured by using ultrasound in centimeters | 30 minutes before induction | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intubation difficulty scale score | Each number of numbers attempt, operator and alternative techniques used, the Cormack Lehane score of laryngoscopic view, lifting force and external laryngeal manipulation required, and position of the vocal cords count 1 point. A score of >5 indicates moderate-to-major difficulty | 1 minutes after intubation |