Thyromental Height Test Versus Sternomental Displacement in Elderly

Difficult Airway Clinical Trial

Official title:

Thyromental Height Test Versus Sternomental Displacement Test for Prediction of Difficult Airway in Elderly Surgical Patients.

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT05414214
• Other study ID #: 45MS-2021
• Status: Completed
• Start date: June 10, 2022
• Est. completion date: September 10, 2022

Study information

• Verified date: September 2022
• Source: Cairo University
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The study is designed to evaluate the validity of the SMDD as a predictor of difficult airway in elderly and to compare its validity with that of the TMHT.

Description:

The airway assessment for difficulty before anesthesia in the elderly is crucial as the delay in the endotracheal intubation in this age group can lead to fatal consequences due to limited organ reserve and comorbidities. Previous studies revealed that elderly patients are predisposed to an increased incidence of difficult airway due to the age-related anatomic changes of the head and neck. These changes include, but not limited to, teeth loss, narrow dental arch, reduced oral soft tissue flexibility, TMJ dysfunction, degenerative change of ligament and tendons of the intervertebral discs causing compression of the intervertebral discs, cervical lordosis and spondylosis, limited head and upper neck extension, and fixed cervical spine flexion deformity.

Sternomental displacement (SMDD) is a relatively new objective airway measure that represents the difference between Sternomental distance that is measured while the head is extended on the neck (SMD-extension) and the Sternomental distance that is measured while the head is in a neutral position (SMD-neutral). The SMDD is a surrogate indicator of neck mobility. Both TMHT and SMDD were proved to be a good objective predictor for difficult laryngoscopy (DL) in adult surgical patients.

The TMHT was proved to have good predictive ability for difficult airway in elderly patients, but to the best of our knowledge, the SMDD was not previously evaluated in elderly. This study was designed to evaluate the validity of the SMDD as a predictor of difficult airway in elderly and to compare its validity with that of the TMHT. Our primary endpoint is the AUROC curve (area under receiver operating characteristic curve), sensitivity, specificity of the SMDD as a predictor of difficult laryngoscopy in elderly surgical patients. The secondary endpoint is to compare the validity of SMDD for predicting difficult airway with that of the TMHT and (Modified Mallampati test) MMT.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 150
• Est. completion date: September 10, 2022
• Est. primary completion date: August 20, 2022
• Gender: All
• Age group: 65 Years to 90 Years

Eligibility

Inclusion Criteria:

1. elderly patients aged = 65 years both male & female .

2. ASA physical status I, II, and III .

3. patients scheduled for elective surgeries under general anesthesia .

Exclusion Criteria:

1. Patients undergoing emergency procedure

2. patients requiring elective awake fiberoptic.

3. patients having neuromuscular disorders or craniofacial abnormalities

4. patients with cervical spine surgeries, neck scars, obvious limited neck extension.

5. morbid obesity (MBI ?40 kg/m2)

Related Conditions & MeSH terms

• Difficult Airway

Intervention

Procedure:
• Thyromental Height Test
Thyromental Height Test (TMHT) : will be measured while a patient is lying supine with the head and neck are maintained in a neutral position using a pillow under the head. By using a digital depth gauge, the TMH is the vertical distance measured between the anterior border of the thyroid cartilage directly on the thyroid notch and the anterior border of the mentum.
• Sternomental displacement
Sternomental displacement (SMDD): While the patient is sitting with the head in a neutral position, SMD-neutral will be measured using a tape as the distance between upper borders of the manubrium sterni and the mentum. The SMD-extension will then be measured in the same way with the head extended on the neck. The difference between SMD-extension and SMD-neutral will then be calculated as SMDD.
• General anesthesia
patients will be pre-oxygenated with 100% oxygen for 3 minutes, anesthesia will be then induced intravenously using fentanyl 2 µg/kg, propofol 1 -1.5 mg/kg, and succinylcholine 1 mg/kg lean body weight. Mask ventilation will be maintained till complete muscle relaxation guided by a peripheral nerve stimulator. Using Macintosh laryngoscopy, an anesthetist who has at least three years experience and who will be blinded to the preoperative tests' results, determined the best laryngeal view by using Cormack-Lehane (CL) grading system from I-IV. External neck manipulation will be used when needed to obtain the best laryngoscopic view. Endotracheal intubation will then be accomplished. The number and duration of intubation attempts will be recorded.

Locations

Country	Name	City	State
Egypt	Faculty of medicine-Cairo University	Cairo

Sponsors (1)

Lead Sponsor	Collaborator
Cairo University

Country where clinical trial is conducted

Egypt, 

References & Publications (3)

Etezadi F, Ahangari A, Shokri H, Najafi A, Khajavi MR, Daghigh M, Moharari RS. Thyromental height: a new clinical test for prediction of difficult laryngoscopy. Anesth Analg. 2013 Dec;117(6):1347-51. doi: 10.1213/ANE.0b013e3182a8c734. — View Citation

Johnson KN, Botros DB, Groban L, Bryan YF. Anatomic and physiopathologic changes affecting the airway of the elderly patient: implications for geriatric-focused airway management. Clin Interv Aging. 2015 Dec 4;10:1925-34. doi: 10.2147/CIA.S93796. eCollection 2015. Review. — View Citation

Prakash S, Mullick P, Bhandari S, Kumar A, Gogia AR, Singh R. Sternomental distance and sternomental displacement as predictors of difficult laryngoscopy and intubation in adult patients. Saudi J Anaesth. 2017 Jul-Sep;11(3):273-278. doi: 10.4103/1658-354X.206798. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	sensitivity, specificity of the sternomental displacement as a predictor of difficult laryngoscopy in elderly surgical patients.		10 minutes
Secondary	Thyromental Height Test (TMHT)	Thyromental Height Test (TMHT): will be measured while a patient is lying supine with the head and neck are maintained in a neutral position using a pillow under the head. By using a digital depth gauge, the TMH is the vertical distance measured between the anterior border of the thyroid cartilage directly on the thyroid notch and the anterior border of the mentum.	10 minutes
Secondary	Sternomental displacement (SMDD)	Sternomental displacement (SMDD): While the patient is sitting with the head in a neutral position, SMD-neutral will be measured using a tape as the distance between upper borders of the manubrium sterni and the mentum. The SMD-extension will then be measured in the same way with the head extended on the neck. The difference between SMD-extension and SMD-	10 minutes
Secondary	Modified Mallampati test (MMT)	Modified Mallampati test (MMT): the patient will be seated in a neutral position, the mouth is maximally opened, tongue protruded, and no phonation. According to the apparent oropharyngeal structures, the proper classification will be recorded.	10 minutes
Secondary	Cormack-Lehane (CL) grading system	Cormack-Lehane (CL) grading system from I-IV. (Grade I: full view of the glottis; grade II: glottis partly exposed, anterior commissure not seen; grade III: only epiglottis seen; grade IV: epiglottis not seen). Grade I &II will be categorized as easy laryngoscopy and grade III and IV as difficult laryngoscopy.	10 minutes
Secondary	The number and duration of intubation attempts		10 minutes