Comparison of Airway Ultrasound Measurements

Not yet recruiting

• Conditions: Intubation; Difficult or Failed

• Registration Number: NCT06928402
• Lead Sponsor: Ankara Ataturk Sanatorium Training and Research Hospital

Brief Summary

Evaluating the success of measurements taken with ultrasound airway imaging in predicting difficult intubation by comparing conventional parameters in terms of difficult intubation and the proportion of patients encountered during intubation and characterised as difficult.

Detailed Description

Clinical screening tests, which have long been routinely used for airway assessment, do not have sufficient sensitivity and specificity to detect difficult laryngoscopy. The Cormack-Lehane laryngoscopy classification, which can be assessed during direct laryngoscopy, is an invasive procedure and is not suitable for routine preoperative airway assessment. Preoperative airway assessment using ultrasound can help to predict a difficult laryngoscopy and/or difficult intubation and is growing in popularity as a non-invasive diagnostic tool. Several recent studies have emphasised the importance of various ultrasound-mediated airway measurements in predicting difficult intubation, and have shown that measurements with different parameters and data obtained by ratioing some measurements to each other may have an important role. However, the parameters obtained by ultrasound-mediated airway measurement can help determine airway anatomy and guide airway interventions with dynamic real-time images.

In this study, we used hyoid bone visibility obtained by preoperative ultrasound evaluation of the upper airway, followed by skin-hyoid distance, skin-cricothyroid membrane distance and length, hyomental distance measured in two different positions, neutral and extension, and the ratios of these two measurements to predict difficult intubation; traditional parameters used as indicators of difficult ventilation and/or intubation (Mallampati-Samsoon classification, upper lip bite test, thyromental distance, sternomental distance, neck circumference, maximum mouth opening, Wilson difficult intubation score and Han ventilation scale).

Study Timeline

• Status Verified: 2025-04
• Study First Submitted: 2025-04-08
• Study First Submitted QC: 2025-04-08
• Last Update Submitted: 2025-04-08
• Study Start: 2025-04-14
• Study First Posted: 2025-04-15
• Last Update Posted: 2025-04-15
• Primary Completion: 2025-08-31
• Study Completion: 2025-09-30

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 420

Inclusion Criteria

• Patients to be operated with endotracheal intubation under elective conditions
• Voluntary patients whose informed consent was obtained,
• Patients older than 18 years
• Patients evaluated in the 1-2-3 category of the American Society of Anaesthesiologist (ASA)

Exclusion Criteria

• Patients with a history of difficult intubation
• Pregnant patients
• Patients with a history of surgery in the head and neck region
• Patients with a history of trauma or tumour in the head and neck region
• Presence of a syndrome that will cause difficult intubation
• Uncooperative patients,
• Patients with missing data

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Ratio of ultrasound-derived parameters with conventional parameters	1 hour peroperatively	ultrasound derived parameters: hyoid bone visibility, skin-hyoid distance, skin-hyoid distance, skin-crricothyroid membrane distance, cricothyroid membrane length and hyomental distance measured in neutral and extension and the ratio of these values.; Conventional parameters: thyromental distance, sternomental distance, upper lip bite test, head-neck movement, presence of retrognathia, neck circumference, maximum mouth opening, Wilson difficult intubation score, Han scale and Mallampati score

Secondary Outcome Measures

Name	Time	Method
Incidence of difficult intubation	1 hour peroperatively	Defined as ≥3 intubation attempts by an experienced anesthesiologist, use of adjunctive devices (e.g., stylet, LMA, video laryngoscope), or duration \>10 minutes.
Incidence of difficult ventilation	1 hour preoperatively	Grade 3 and 4 for Han scale.( Difficulty of mask ventilation (DMV) has been classified using the Han scale.)