TMHT - Difficult Intubation Prediction Using Videolaryngoscopy

Not Applicable

Completed

• Conditions: Predictive Value of Tests; Intubation
• Interventions: Procedure: McGrath MAC video laryngoscopy; Procedure: Macintosh laryngoscopy

• Registration Number: NCT03647371
• Lead Sponsor: Medical University of Silesia

Brief Summary

The purpose of this study is to assess the usefulness of the Thyromental Height Test in prediction of difficult intubation using videolaryngoscopy and double lumen endotracheal tubes in patients scheduled for elective thoracic procedures.

Detailed Description

Successful and fast intubation are crucial for the safety of general anaesthesia. Failed intubation and acute hypoxia remain among the major contributing factors of anaesthesia related deaths. Difficult intubation prevalence in literature is very inconsistent and varies between 1.5-20% of cases in general population, to even 50% in obese Thai population.

There is a number of anthropometric scales and tests used for predicting difficult intubation. However, none of them appears to be sensitive and specific enough to effectively predict difficult intubation.

Recently, simple and non-invasive test predicting difficult intubation was introduced-thyromental height test (TMHT). It shows promise as a more effective substitution for frequently cited anthropometric measures. It is based on the height between the anterior border of the thyroid cartilage and the anterior border of the mentum, measured while the patient lies in the supine position with closed mouth The main objective of the trial is to assess the clinical usefulness of TMHT in prediction of difficult intubation using videolaryngoscopy and double lumen endotracheal tubes in patients scheduled for elective thoracic surgical procedures. The secondary aim is to evaluate usefulness of other commonly used predictive tests associated with difficult intubation.

During routine, preoperative anaesthetic visit thyromental height, thyromental distance, sternomental distance and Mallampati scale score are assessed. Then, during videolaryngoscopy and intubation, score in Cormack-Lehane scale and occurrence of difficult intubation are noted.

Study Timeline

• Study First Submitted: 2018-08-05
• Study Start: 2018-08-06
• Study First Submitted QC: 2018-08-23
• Study First Posted: 2018-08-27
• Primary Completion: 2019-11-05
• Study Completion: 2019-11-05
• Status Verified: 2020-04
• Last Update Submitted: 2020-04-12
• Last Update Posted: 2020-04-14

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 200

Inclusion Criteria

• patients scheduled for elective thoracic procedures, requiring general anaesthesia, videolaryngoscopy and intubation with a Robert-Shaw type double lumen endotracheal tubes
• written, informed consent for participation in the trail
• older than 18 years

Exclusion Criteria

• emergency procedures
• visible anatomic abnormalities
• patients scheduled for awake fibre optic intubation
• lack of consent for participation in the trail

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
McGrath videolaryngoscope	McGrath MAC video laryngoscopy	McGrath Videolaryngoscope
Macintosh laryngoscope	Macintosh laryngoscopy	direct laryngoscope - laryngoscope with Macintosh blade

Primary Outcome Measures

Name	Time	Method
Thyromental height	From August 6 2018 to August 5 2019.	The height between the anterior border of the thyroid cartilage (on the thyroid notch just between the 2 thyroid laminae) and the anterior border of the mentum (on the mental protuberance of the mandible), in supine position with mouth closed, measured with a depth gauge during routine preoperative anaesthetic visit.

Secondary Outcome Measures

Name	Time	Method
core in modified Mallampati test	From August 6 2018 to August 5 2019.	The oropharyngeal view is assessed in sitting position, mouth maximally opened, tongue protruded, without phonation, measured during routine preoperative anaesthetic visit.
Thyromental distance	From August 6 2018 to August 5 2019.	The distance between the thyroid prominence and the most anterior part of the mental prominence of the mandible, measured with a standard centigrade ruler as the distance in centimetres with the patient in supine position, head fully extended, mouth closed, during routine preoperative anaesthetic visit.
Sternomental distance	From August 6 2018 to August 5 2019.	The distance in centimetres between the superior border of the manubrium sterni and the bony point of the mentum, with the patient in supine position, head fully extended, mouth closed, measured with a standard centigrade ruler, during routine preoperative anaesthetic visit.
score in Cormack-Lehane scale	From August 6 2018 to August 5 2019.	During videolaryngoscopy the laryngeal view is graded in Cormack-Lehane Scale by the laryngoscopist. Grade I is assigned when the glottis is fully visible, grade II when the glottis is partially visible, grade III when only the epiglottis is visible and grade IV when neither glottis nor epiglottis is visible.
distance of mouth opening	From August 6 2018 to August 5 2019.	Measured as a distance between the lower and upper incisors with a tape measure (Standard, Hoechstmas, Sulzbach, Germany) as a distance in centimetres. Patients are in sitting position with mouth maximally opened, tongue retracted and without phonation.

Trial Locations

Locations (1)

Samodzielny Publiczny Szpital Kliniczny nr 1; 🇵🇱 Zabrze, Silesia, Poland