Assessment Of Difficult Airway Predictors: A Prospective Comparison Of Upper Airway Ultrasound And Conventional Anthropometric Measures

This prospective observational study aims to evaluate whether upper airway ultrasound measurements can improve the prediction of difficult airway compared with conventional anthropometric assessments. Adult patients undergoing elective procedures requiring airway management will be included. Ultrasound parameters such as tongue thickness, anterior neck soft tissue thickness, and hyomental distance will be measured before airway intervention. Standard clinical predictors (Mallampati score, thyromental distance, neck circumference, etc.) will also be recorded. The primary objective is to determine the diagnostic accuracy of ultrasound-based measurements in predicting difficult laryngoscopy and intubation. The study seeks to provide evidence supporting the integration of upper airway ultrasound into routine pre-anesthetic airway evaluation.

Study Overview

• Status: Recruiting
• Conditions: Difficult Airway Intubation; Prediction of Difficult Airway

• Study Type: Observational
• Enrollment (Estimated): 200

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Ankara, Turkey (Türkiye)
    • Recruiting
    • Sağlık Bilimleri Üniversitesi
    • Contact: sami eksert, MD, Assoc. Prof.; Phone Number: +90 532 562 0597; Email: exert79@yahoo.com

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

The study population consists of adult patients (18-99 years) scheduled for elective surgery under general anesthesia at a tertiary care hospital. Participants represent typical surgical patients requiring preoperative airway assessment. No healthy volunteers will be enrolled. Only ASA I-III patients who can provide informed consent will be included.

Description

Inclusion Criteria:

• Adults aged 18-99 years
• Patients scheduled for elective surgery under general anesthesia
• ASA Physical Status I-III
• Able to provide informed consent
• Undergoing preoperative airway evaluation

Exclusion Criteria:

• - Emergency surgery cases
• Age <18 years
• ASA Physical Status IV-V
• Pregnant or breastfeeding patients
• Patients with limited cooperation or inability to provide consent
• Known anatomical airway anomalies or previous major neck surgery

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Single Cohort; This cohort includes all adult participants undergoing airway evaluation with upper airway ultrasound and standard anthropometric measurements. No interventions are applied; participants are observed prospectively to assess the predictive value of ultrasound parameters for difficult airway.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diagnostic accuracy of ultrasound airway measurements for predicting difficult mask ventilation	Evaluation of the sensitivity, specificity, and area under the ROC curve (AUC) of ultrasound-based airway measurements-tongue thickness, hyoid-to-skin distance, and epiglottis-to-skin distance-in predicting difficult mask ventilation. These ultrasound parameters will be compared with conventional anthropometric airway assessment tests to determine their predictive performance.	Preoperative assessment (within 1 hour before induction of anesthesia)

Collaborators and Investigators

• Sponsor: Saglik Bilimleri Universitesi Gulhane Tip Fakultesi

Publications and helpful links

General Publications

• Yao W, Wang B. Can tongue thickness measured by ultrasonography predict difficult tracheal intubation? Br J Anaesth. 2017 Apr 1;118(4):601-609. doi: 10.1093/bja/aex051.
• Rastogi A, Singh AK, Srivastava D, Kannaujia AK, Singh TK, Mishra P. Evaluation of ultrasound measured tongue thickness, tongue thickness-thyromental distance ratio, and skin-to-epiglottis distance in predicting unanticipated difficult laryngoscopy. J Anaesthesiol Clin Pharmacol. 2025 Jan-Mar;41(1):151-157. doi: 10.4103/joacp.joacp_423_23. Epub 2025 Jan 23.
• Roth D, Pace NL, Lee A, Hovhannisyan K, Warenits AM, Arrich J, Herkner H. Airway physical examination tests for detection of difficult airway management in apparently normal adult patients. Cochrane Database Syst Rev. 2018 May 15;5(5):CD008874. doi: 10.1002/14651858.CD008874.pub2.

Study record dates

Study Major Dates

• Study Start (Actual): December 25, 2025
• Primary Completion (Estimated): July 25, 2026
• Study Completion (Estimated): December 25, 2027

Study Registration Dates

• First Submitted: December 16, 2025
• First Submitted That Met QC Criteria: December 16, 2025
• First Posted (Actual): December 30, 2025

Study Record Updates

• Last Update Posted (Actual): March 10, 2026
• Last Update Submitted That Met QC Criteria: March 6, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: AEŞH-EK-2-25-276

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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