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Evaluation of Difficult Airway With Ultrasonography

Evaluation of Difficult Airway in Obese Patients With Ultrasonography

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04289597
Enrollment
128
Registered
2020-02-28
Start date
2020-08-20
Completion date
2022-03-11
Last updated
2022-03-14

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

Conditions

Difficult Intubation, Obesity

Keywords

Difficult mask, Difficult laryngoscopy, Difficult intubation

Brief summary

As a result of anatomical and physiological changes in obese patients, airway management can be challenging. Ultrasound measurement of neck anterior soft tissues combined with recommended predictive tests may increase the ability to predict the difficult airway. In this study we planned to evaluate the measurement of neck anterior soft tissues by ultrasound in obese patients before anesthesia induction to anticipate difficult mask ventilation, difficult laryngoscopy, and intubation.

Detailed description

Patients with BMI\> 30, schedule elective surgery under general anesthesia, and give consent will be included in the study. In the preoperative evaluation, demographic data of the patients, airway physical examination results (mouth opening, Mallampati score, thyromental distance, neck circumference (from thyroid cartilage level), abnormal upper tooth presence, neck movement restriction\], presence of sleep apnea and STOP-BANG score will be recorded. In the patients taken on the operation table with supine position, ultrasound-guided soft tissue distances will be measured using ultrasound 6-13 Hz linear probe. The distance between the hyoid bone-skin (DSHB), the vocal cord anterior commissura-skin distance (DSAC), the minimum distance of the trachea to the skin at the level of the suprasternal notch (DST), the distance between the thyroid isthmus and the skin (DSI), and the distance between the epiglottis and the skin (DSE) will be measured and recorded. After standard monitoring and anesthesia induction, difficult mask ventilation will be evaluated with Han Scale \[(1) can be ventilated with a mask; 2) can be ventilated with the airway (with or without muscle relaxation); 3) difficult mask ventilation (insufficient, unstable, two practitioners are needed); 4) cannot be ventilated by mask\] and grade 3-4 will be recorded as difficult mask ventilation. Difficult laryngoscopy will be evaluated with Cormack Lehane Scale \[grade 1: vocal cords appear; grade-2: posterior commissura and epiglottis visible; grade-3: only epiglottis are seen; grade-4: glottic structures are not visible\] and grade 3-4 will be recorded as difficult laryngoscopy. Difficult intubation will also be evaluated with the number and duration of intubation attempts with the Macintosh blade. Tracheal intubation will be performed by an anesthesiologist who has at least two years of experience and unaware of ultrasound measurements. The duration of intubation (the time from the first handling of the laryngoscope until the capnography trace appeared) and the number of trials will be recorded.

Interventions

DIAGNOSTIC_TESTDistance between hyoid bone-skin (DSHB)

Distance between hyoid bone-skin

DIAGNOSTIC_TESTVocal cord anterior commissura-skin distance (DSAC)

Vocal cord anterior commissura-skin distance

DIAGNOSTIC_TESTminimum distance of the trachea to the skin at the level of suprasternal notch

Distance of the trachea to the skin at the level of suprasternal notch

DIAGNOSTIC_TESTThyroid isthmus-skin distance (DSI)

Thyroid isthmus-skin distance

DIAGNOSTIC_TESTSkin-epiglottic distance (DSE)

Skin-epiglottic distance

Sponsors

Eskisehir Osmangazi University
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes

Inclusion criteria

* Patients planned to undergo general anesthesia for elective surgery * American Anesthesiology Association physical classification (ASA) status I-III * Body mass index (BMI) above 30

Exclusion criteria

* Patients with neck mass * History of previous neck and thyroid surgery, trauma, arthritis, loss of teeth * History of difficult intubation * Bearded patients * Pregnant women

Design outcomes

Primary

MeasureTime frameDescription
Difficult Mask Ventilation''1 minute'' (During anesthesia induction)Difficult mask ventilation will be evaluated with Han scale \[(1) can be ventilated with a mask; 2) can be ventilated with the airway (with or without muscle relaxation); 3) difficult mask ventilation (insufficient, unstable, two practitioners are needed); 4) cannot be ventilated by mask\] and grade 3-4 will be recorded as difficult mask ventilation.

Secondary

MeasureTime frameDescription
Difficult laryngoscopy''1 minute''Difficult laryngoscopy will be evaluated Cormack Lehane Scale \[grade 1: vocal cords appear; grade-2: posterior commissura and epiglottis visible; grade-3: only epiglottis are seen; grade-4: glottic structures are not visible\] and grade 3-4 will be recorded as difficult laryngoscopy.
Difficult intubation''1 minute''Total number of intubation attempts
The duration of endotracheal intubation time1 minuteThe time from the first handling of the laryngoscope until the capnography trace appeared

Countries

Turkey (Türkiye)

Outcome results

None listed

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