Clinical trial NCT04289597: Evaluation of Difficult Airway With Ultrasonography
Official title: Evaluation of Difficult Airway in Obese Patients With Ultrasonography
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Difficult Intubation
Obesity
Keywords: Difficult mask
Difficult laryngoscopy
Difficult intubation
Lead sponsor: Eskisehir Osmangazi University
Sponsor class: OTHER
First posted: 2020-02-28
Enrollment: 128
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: A hundred twenty-eight patients, aged 18-65 years-old, with an American Anesthesiology Association physical classification (ASA) I-III and body mass index (BMI) above 30 and planned to undergo general anesthesia for elective surgery, will be included in the study.

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.

Eligibility criteria: 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

Primary outcomes:
measure: Difficult Mask Ventilation
timeFrame: ''1 minute'' (During anesthesia induction)
Secondary outcomes:
measure: Difficult laryngoscopy
timeFrame: ''1 minute''
measure: Difficult intubation
timeFrame: ''1 minute''
measure: The duration of endotracheal intubation time
timeFrame: 1 minute
Other outcomes:
Locations:
city: Odunpazarı
country: Turkey
facility: Eskisehir Osmangazi Univercty
state: Eskisehir
Study officials:
affiliation: Teaching Assistant
name: Meryem Onay, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Wu J, Dong J, Ding Y, Zheng J. Role of anterior neck soft tissue quantifications by ultrasound in predicting difficult laryngoscopy. Med Sci Monit. 2014 Nov 18;20:2343-50. doi: 10.12659/MSM.891037.
citation: Ezri T, Gewurtz G, Sessler DI, Medalion B, Szmuk P, Hagberg C, Susmallian S. Prediction of difficult laryngoscopy in obese patients by ultrasound quantification of anterior neck soft tissue. Anaesthesia. 2003 Nov;58(11):1111-4. doi: 10.1046/j.1365-2044.2003.03412.x.
citation: Liang H, Hou Y, Wei H, Feng Y. Supraglottic jet oxygenation and ventilation assisted fiberoptic intubation in a paralyzed patient with morbid obesity and obstructive sleep apnea: a case report. BMC Anesthesiol. 2019 Mar 20;19(1):40. doi: 10.1186/s12871-019-0709-7.
citation: Murphy C, Wong DT. Airway management and oxygenation in obese patients. Can J Anaesth. 2013 Sep;60(9):929-45. doi: 10.1007/s12630-013-9991-x. Epub 2013 Jul 9.
citation: Lundstrom LH, Moller AM, Rosenstock C, Astrup G, Wetterslev J. High body mass index is a weak predictor for difficult and failed tracheal intubation: a cohort study of 91,332 consecutive patients scheduled for direct laryngoscopy registered in the Danish Anesthesia Database. Anesthesiology. 2009 Feb;110(2):266-74. doi: 10.1097/ALN.0b013e318194cac8.
citation: Chung F, Subramanyam R, Liao P, Sasaki E, Shapiro C, Sun Y. High STOP-Bang score indicates a high probability of obstructive sleep apnoea. Br J Anaesth. 2012 May;108(5):768-75. doi: 10.1093/bja/aes022. Epub 2012 Mar 8.
citation: Alessandri F, Antenucci G, Piervincenzi E, Buonopane C, Bellucci R, Andreoli C, Alunni Fegatelli D, Ranieri MV, Bilotta F. Ultrasound as a new tool in the assessment of airway difficulties: An observational study. Eur J Anaesthesiol. 2019 Jul;36(7):509-515. doi: 10.1097/EJA.0000000000000989.