Role of Airwayultrasound in Predicting Difficult Endotracheal Intubation in Patients Undergoing General Anesthesia

Unpredictable difficult endotracheal intubation remains a challenge especially if difficult ventilation occurs. Difficult intubation is associated with many severe fatal complications including air way trauma, laryngospasm, hypoxemia, arrhythmias and potential cardiac arrest. Therefore, preoperative evaluation and prediction of potential difficult airway is very important.

Several screening tests are used in clinical practice to identify patients at the risk of difficult airway. Despite their accuracy and benefit, a small number of patients classified to an easy airway may still present an unexpected difficulty. Predicting a difficult airway is not at all an easy task for all patients .

Incidence of difficult airway and difficult intubation varies from 5% to 22% with important implications for clinical practice and patients' outcomes .

There are multiple scores used for airway assesment ,the commonest one is LEMON score. LEMON is an airway assessment score that measures factors associated with difficult intubation such as obesity, head and neck movement, jaw movement , receding mandible, long upper incisors, Mallampatti scores, maxillary incisor characteristics, decreased mouth opening ,shorten thyromental distance and short neck .

Diagnostic criteria for LEMON scoring system :

L- Look. E- Evaluation using the 3-3-2 rule. M- Mallampati. O- Obstruction. N- Neck mobility. Ultrasound (US) imaging technique is simple, portable, noninvasive tool helpful for airway assessment and management. In the last few years, there have been some reports that described various roles of US imaging in airway management. It helps in rapid assessment of the airway anatomy, not only in operation theatre but also in the intensive care unit and emergency department.

Various clinical applications of US imaging of the upper airway include identification of endotracheal tube (ETT) placement, guidance of percutaneous tracheostomy and cricothyroidotomy, detection of subglottic stenosis, prediction of difficult intubation and post-extubation stridor, prediction of paediatric ETT and double-lumen tube (DLT) size.

Recently there are researches about airway assesment by ultrasound. Several airway assesment indicies are used to help in prediction of difficult endotracheal intubation. The most commonly used indices are distance from skin to epiglottis, distance from skin to vocal cord level, and distance from skin to hyoid bone.

Study Overview

• Status: Not yet recruiting
• Conditions: Predict Diificult Endotracheal Intubation
• Intervention / Treatment: Device: assesment of difficult endotracheal intubation by airway ultrasound

• Study Type: Observational
• Enrollment (Estimated): 170

Contacts and Locations

• Study Contact: Name: Meril N Saleeb, resident; Phone Number: 01287178283; Email: mirelnasry@med.sohag.edu.eg
• Study Contact Backup: Name: Abdelrahman H Abdelrahman, professor

Study Locations

• Egypt
  • Sohag, Egypt
    • Sohag University Hospital
    • Contact: Magdy M Amin, Professor

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Adult patients from 18- 50 yrs old Patients who require endotracheal intubation for surgery under general anesthesia.

Description

Inclusion Criteria:

• Adult patients from 18- 50 yrs old
• Patients who require endotracheal intubation for surgery under general anesthesia.

Exclusion Criteria:

• Patients with history of previous difficult intubation.
• Neck deformity such as swelling , scar ,etc.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ultasound airway assesment index ..distance from skin to epiglottis	to measure distance from skin to epiglottis	6 months
ultasound airway assesment index ..distance from skin to hyoid bone	to measure distance from skin to hyoid bone	6 months
ultasound airway assesment index ..distance from skin to vocal cord	to measure distance from skin to vocal cord	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
airway ultrasound and LEMON score	compare between LEMON score and airway ultrasound in predicting difficult airway.	6 months

Collaborators and Investigators

• Sponsor: Sohag University

Publications and helpful links

General Publications

• Cook TM, Woodall N, Frerk C; Fourth National Audit Project. Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society. Part 1: anaesthesia. Br J Anaesth. 2011 May;106(5):617-31. doi: 10.1093/bja/aer058. Epub 2011 Mar 29.
• Frerk C, Mitchell VS, McNarry AF, Mendonca C, Bhagrath R, Patel A, O'Sullivan EP, Woodall NM, Ahmad I; Difficult Airway Society intubation guidelines working group. Difficult Airway Society 2015 guidelines for management of unanticipated difficult intubation in adults. Br J Anaesth. 2015 Dec;115(6):827-48. doi: 10.1093/bja/aev371. Epub 2015 Nov 10.
• Roth D, Pace NL, Lee A, Hovhannisyan K, Warenits AM, Arrich J, Herkner H. Bedside tests for predicting difficult airways: an abridged Cochrane diagnostic test accuracy systematic review. Anaesthesia. 2019 Jul;74(7):915-928. doi: 10.1111/anae.14608. Epub 2019 Mar 6.
• Detsky ME, Jivraj N, Adhikari NK, Friedrich JO, Pinto R, Simel DL, Wijeysundera DN, Scales DC. Will This Patient Be Difficult to Intubate?: The Rational Clinical Examination Systematic Review. JAMA. 2019 Feb 5;321(5):493-503. doi: 10.1001/jama.2018.21413. Erratum In: JAMA. 2020 Mar 24;323(12):1194.

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2023
• Primary Completion (Estimated): January 31, 2024
• Study Completion (Estimated): January 31, 2024

Study Registration Dates

• First Submitted: July 18, 2023
• First Submitted That Met QC Criteria: July 18, 2023
• First Posted (Actual): July 27, 2023

Study Record Updates

• Last Update Posted (Actual): July 27, 2023
• Last Update Submitted That Met QC Criteria: July 18, 2023
• Last Verified: July 1, 2023

More Information

Terms related to this study

• Other Study ID Numbers: Soh-Med-23-07-19MS

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No