Using neck ultrasound to predict difficult breathing tube placement in adults with obesity
Compares airway ultrasound with usual exam methods in adults with obesity having surgery.
Plain-language title generated from the registry record
Registry title: Ultrasound vs Clinical Parameters for Difficult Airway Prediction in Obesity
Key facts
- Where
- Istanbul, TürkiyeSee the site
AI summary: who the study is looking for
From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.
The trial is looking for adults aged 18-65 with obesity (BMI >30 kg/m2) who are having planned surgery under general anesthesia with a breathing tube.
- Age
- 18-65 years
- Sex
- All sexes can join.
- Disease stage
- Obesity with BMI >30 kg/m2. Health status ASA I, II or III. Planned (elective) surgery that needs a breathing tube through the mouth under general anesthesia.
- Earlier treatment
- No previous head and neck surgery or radiotherapy.
Main reasons for not taking part
- Emergency surgery
- Previous head and neck surgery or radiotherapy
- Known or expected difficult airway, or past difficult intubation
- Neck spine problem or limited neck movement
- Pregnancy
Read by machine on 12 November 2026.
Could this be for you?
Answer for yourself. This is not a decision: only the study team can say whether you can take part.
- Are you between 18 and 65 years old?
Source: NCT07528677, who can take part
Where in Türkiye
- Fatih Sultan Mehmet Training and Research HospitalIstanbul, TürkiyeContact: cansu ofluoglu, MDNo longer taking part
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Contact the study team: see the registry record → Contacts and Locations
Print a page for my doctorTrial details
- Who runs it
- Fatih Sultan Mehmet Training and Research Hospital
- Trial code
- NCT07528677
- Record updated
- 14 April 2026
- Original description
Obesity is associated with anatomical changes in the upper airway that increase the risk of difficult laryngoscopy and difficult mask ventilation during anesthesia. Conventional airway assessment parameters such as Mallampati score, neck circumference, and STOP-BANG scale are widely used but have limited predictive accuracy in obese patients. Airway ultrasonography has emerged as a promising non-invasive tool for difficult airway prediction; however, ultrasonographic criteria have not yet been standardized.Read full original descriptionShow less
Comparison of Airway Ultrasonography and Conventional Difficult Airway Parameters for Predicting Difficult Airway in Obese Patients: A Prospective Observational Study
Obesity is associated with anatomical changes in the upper airway that increase the risk of difficult laryngoscopy and difficult mask ventilation during anesthesia. Conventional airway assessment parameters such as Mallampati score, neck circumference, and STOP-BANG scale are widely used but have limited predictive accuracy in obese patients. Airway ultrasonography has emerged as a promising non-invasive tool for difficult airway prediction; however, ultrasonographic criteria have not yet been standardized.
This prospective observational study aims to evaluate the utility of airway ultrasonography in predicting difficult airway in adult obese patients (BMI >30 kg/m²) scheduled for elective surgery under general anesthesia. Ultrasonographic measurements will include the distance from skin to hyoid bone (DSHB) at the level of the hyoid bone, the anterior neck soft tissue thickness at the thyrohyoid membrane level, and the hyomental distance ratio (HMDR). These parameters will be compared with conventional airway assessment tools and correlated with intraoperative Cormack-Lehane laryngoscopy grade and Han Scale mask ventilation score to determine their predictive value for difficult airway.
Inclusion: Age 18-65 years; BMI >30 kg/m2; ASA physical status I, II, or III; Scheduled for elective surgery requiring orotracheal intubation under general anesthesia; Written informed consent obtained.
Exclusion: Emergency surgery; History of previous head and neck surgery or radiotherapy; Known or anticipated difficult airway (history of difficult intubation); Presence of cervical spine pathology or limited neck mobility; Presence of oropharyngeal or laryngeal pathology; Pregnancy; Patients with tracheostomy; Refusal to participate.