Indirect Laryngoscopy and Ultrasonography in Prediction of Difficult Airway

The Role of Indirect Laryngoscopy, Clinical and Ultrasonographic Assessment in Prediction of Difficult Airway

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT04226703

Enrollment

140

Registered

2020-01-13

Start date

2019-06-15

Completion date

2019-12-15

Last updated

2020-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Difficult Intubation

Keywords

airway, laryngoscopy, ultrasonography

Brief summary

This study was designed to assess the success of indirect laryngoscopy and ultrasonographic measurements in the prediction of difficult airway. All patients were examined by indirect laryngoscopy and ultrasonography preoperatively and the predictive values for difficult airway of these methods were compared.

Detailed description

Difficult airway is a condition that increases the patient's vital risk and leaves the anesthesia and surgical team in a difficult position. Failure to perform an adequate preoperative evaluation may result in the team being unprepared. Therefore, various methods have been investigated in the prediction of difficult airway from past to present. With the development of technology, imaging methods have become routine applications in clinical use. Ultrasonography and indirect laryngoscopy have been shown to be used in predicting difficult airway in the literature, but there is no study showing which is a better predictor.

Interventions

DIAGNOSTIC_TESTUltrasonographic upper airway measurements

Ultrasonographic upper airway measurements: Epiglottis-skin distance, Hyoid bone-skin distance, Anterior commissure-skin distance and Thickness of tounge root. Indirect Laryngoscopy: Grading of laryngoscopic view (I=Visible anterior commissure and vocal cords, II= visible posterior part of vocal cords and posterior commissure, III= Visible posterior commissure and epiglottis, IV= Visible only epiglottis tip and posterior pharyngeal wall)

Study design

Observational model

COHORT

Time perspective

CROSS_SECTIONAL

Eligibility

Sex/Gender

ALL

Age

18 Years to 70 Years

Healthy volunteers

Yes

Inclusion criteria

* Subject is operated in ear, nose and throat department. * Subject over the age of 18. * Subject giving consent to participate in the study.

Exclusion criteria

* Subject under the age of 18 * Subject with a history of radiotherapy in the head and neck region, * Subject with facial deformity, * Subject whose neck movements have been restricted by previous trauma or surgery, * Subject has laryngeal disease * Previously operated subject with known airway assessment * Morbidly obese subject with BMI\> 40

Design outcomes

Primary

Measure	Time frame	Description
Indirect Laryngoscopic Grade	The day before surgery	The otolaryngologist,who is blind about ultrasonographic airway measurements of patients, performs indirect laryngoscopy and evaluates the laryngeal view.
Cormack-Lehane Classification	Three minutes after induction of anesthesia.	The anesthesiologist, who is blind about indirect laryngoscopy findings and ultrasonographic airway measurements, performs intubation and evaluates the laryngeal view.
Epiglottis skin distance in centimeters.	Five minutes before induction of anesthesia.	The anesthesiologist, who is blind about indirect laryngoscopy findings and is experienced user of ultrasonography, measures epiglottis to skin distance.
Hyoid bone-skin distance in centimeters.	Five minutes before induction of anesthesia.	The anesthesiologist, who is blind about indirect laryngoscopy findings and is experienced user of ultrasonography, measures hyoid bone to skin distance.
Anterior commissure-skin distance in centimeters.	Five minutes before induction of anesthesia.	The anesthesiologist, who is blind about indirect laryngoscopy findings and is experienced user of ultrasonography, measures anterior commissure to skin distance.
Thickness of tongue root in centimeters.	Five minutes before induction of anesthesia.	The anesthesiologist, who is blind about indirect laryngoscopy findings and is experienced user of ultrasonography, measures thickness of tongue root.

Secondary

Measure	Time frame	Description
Thyromental distance in centimeters	The day before surgery	The distance between thyroid notch and mentum. Evaluated by the anesthesiologist who performs intubation.
Sternomental distance in centimeters.	The day before surgery	The distance between sternal notch and mentum. Evaluated by the anesthesiologist who performs intubation.
Neck circumference in centimeters.	The day before surgery	Evaluated by the anesthesiologist who performs intubation.
Mallampati classification	The day before surgery	Evaluated by the anesthesiologist who performs intubation.
Body mass index (BMI)	The day before surgery	Weight and height will be combined to report BMI in kg/m\^2.Evaluated by the anesthesiologist who performs intubation.

Countries

Turkey (Türkiye)

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026