Learning Curve of Endobronchial Intubation Using Video Laryngoscopes

Study Overview
=================
Brief Summary
-----------------
The use of video laryngoscopes for endobronchial intubation has its own potential benefits particularly in case of airway difficulty. It is not clear how many cases are required to show competency in successful endobronchial intubation using McGrath and King Vision video laryngoscopes in simulated easy and difficult airways by novices. The here proposed randomized crossover clinical trial will test the learning curve of using each of McGrath and King Vision video laryngoscopes in simulated easy and difficult airways with respect to the number of intubation trials for successful endobronchial intubation

Detailed Description
-----------------
Surgeries that require lung isolation have been using double-lumen tubes (DLT) for endobronchial intubation as the preferred method due to its numerous advantages. However, the larger diameter of the DLT compared to the single-lumen tube can be more difficult to insert during intubation. [1] The use of video laryngoscopes (VL), which were found to have lower rates of intubation failure, reduced incidences of tracheal and laryngeal trauma, improved glottic view, and increased ease of use, are gaining interest for its use in endobronchial intubation. [2, 3] The use of McGrath® VL systems for DLT endobronchial intubation has been studied and compared to that of conventional laryngoscopy, as well as that of other VL systems. When compared to the conventional Macintosh laryngoscope, McGrath® VL has been consistently associated with a better glottic visualization. [4 - 6] Other advantages include reduced need for external laryngeal manipulation and a lower rate of intubation-associated complications, such as bronchospasm and trauma to the oral mucosa. [7] However, results regarding time to intubation have been controversial. The use of King Vision® VL for DLT endobronchial intubation has not been studied as much as the McGrath® video laryngoscope. Two studies compared the King Vision® VL system to the conventional Macintosh laryngoscope and to other VL systems. When comparing King Vision® to Macintosh laryngoscope, the time to intubation was comparable between the two devices. [8, 9] However, one study found that in a simulated easy airway, a significantly longer time to intubation was shown with King Vision® VL. [9] King Vision® VL and Macintosh laryngoscope were also comparable in terms of glottic visualization, intubation difficulty, first-pass success rates, need for optimizing maneuvers, and postoperative symptoms indicative of pharyngeal or laryngeal trauma. [8, 9] Therefore, competency in endobronchial intubation using video aided laryngoscopes is built through continuous and regular hands-on training. [10] The learning curve of the novice is usually monitored aiming to detect when satisfactory performances are reached. This is widely done using the cumulative sum analysis (CUSUM) test, which provides an objective evaluating method of skill learning via ongoing monitoring. [11] Educational Course. All participants will attend a 30-minutes didactic virtual training course on the Zoom platform equipped with a slide presentation including a demonstrative video on the endobronchial intubation and the tips and tricks for using the two study devices. Additionally, a 5-minute hands-on practice session would be provided on each simulated airway model under close supervision by the investigators (AK, MK, SS, and TAG). Before each DLT intubation attempt, the manikin, laryngoscope blade, and DLT will be lubricated. After completing the DLT intubation, participants should have a 15-minute break before performing intubation using another laryngoscope. All intubations will be performed with a 35-Fr left-side DLT. The participants will not be allowed to watch each other to avoid any learning effect through observation. DATA ANALYSIS Updated and finalized statistical analysis plan will be written, before closing the database.

Official Title
-----------------
Endobronchial Intubation With the King Vision and McGrath Laryngoscopes in Simulated Easy and Difficult Airways by Novices. (eKingMath)

Conditions
-----------------
Endobronchial Intubation

Intervention / Treatment
-----------------
* Other: The simulated easy airway
* Other: The simulated difficult airway
* Device: King Vision Laryngoscope
* Device: MacGrath Laryngoscope


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Novice medical school students in using the devices tested. Are not familiar with double-lumen tube (DLT) insertion. Having no previous experience with the two tested video laryngoscopes for tracheal intubation. Exclusion Criteria: Decline consent to participate. No written informed consent.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: A single-center, interventional, crossover, single-blind (participant), prospective, trial in simulated easy and difficult airway. The study will be conducted according to Good Clinical Practice (GCP) Guidelines and abide by the principles of the Declaration of Helsinki.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: McGrath-King Vision<br>The participants will attempt double-lumen tube intubation using the McGrath (X-blade) laryngoscope then they will use the King Vision (channelled blade size 3) in the same order. | Other: The simulated easy airway<br>* A high-fidelity simulator (Airway Management Trainer, model AA-3100, Laerdal Medical Ltd., Orpington, England, UK) will be equipped to create an easy airway situation by adjusting the manikin until it becomes in a neutral position<br>Other: The simulated difficult airway<br>* A high-fidelity simulator (Airway Management Trainer, model AA-3100, Laerdal Medical Ltd., Orpington, England, UK) will be equipped to create a difficult airway scenario will be established by placing the occiput on an Oasis Elite™ Prone Head Rest, Adult (140 mm in height) (Covidien, Mansfield, MA, USA), and inhibiting head and neck movement by securing the head with an adhesive tape, simulating the effect produced by a cervical-collar.<br>Device: King Vision Laryngoscope<br>* Using a King Vision Laryngoscope for placement of the DLT<br>Device: MacGrath Laryngoscope<br>* Using a MacGrath Laryngoscope for placement of the DLT<br>|
| Active Comparator: King Vision-McGrath<br>The participants will attempt double-lumen tube intubation using the King Vision (channelled blade size 3) then they will use the McGrath (X-blade) laryngoscope in the same order. | Other: The simulated easy airway<br>* A high-fidelity simulator (Airway Management Trainer, model AA-3100, Laerdal Medical Ltd., Orpington, England, UK) will be equipped to create an easy airway situation by adjusting the manikin until it becomes in a neutral position<br>Other: The simulated difficult airway<br>* A high-fidelity simulator (Airway Management Trainer, model AA-3100, Laerdal Medical Ltd., Orpington, England, UK) will be equipped to create a difficult airway scenario will be established by placing the occiput on an Oasis Elite™ Prone Head Rest, Adult (140 mm in height) (Covidien, Mansfield, MA, USA), and inhibiting head and neck movement by securing the head with an adhesive tape, simulating the effect produced by a cervical-collar.<br>Device: King Vision Laryngoscope<br>* Using a King Vision Laryngoscope for placement of the DLT<br>Device: MacGrath Laryngoscope<br>* Using a MacGrath Laryngoscope for placement of the DLT<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The learning curve of using the device tested | The learning curve will be measured with the successful endobronchial intubation within 180 seconds on simulated easy and difficult airways using McGrath and King Vision video laryngoscopes by cumulative sum (CUSUM) analysis using an EXCEL Spreadsheet. Performance of the participants will be assessed for the duration of the study until completing 25 intubation attempts on each of the simulated easy and difficult airway models with a minimum of one day apart from each model. 25 intubation attempts | through study completion, an average of 1 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to endobronchial intubation | The time needed to achieve endobronchial intubation, which starts from the passage of the video laryngoscope through the central incisors to when the tip of the bronchial lumen passes through the glottis, as confirmed by the investigator through the display screens. | for 180 seconds from the passage of the video laryngoscope through the central incisors | 
| Time to placement of the endobronchial tube | The time to placement of the endobronchial tube in the left main bronchus | for 360 seconds from the passage of the video laryngoscope through the central incisors | 
| Percentage of glottic opening (POGO) score | The best view during laryngoscopy using the classification described by percentage of glottic opening (POGO) score | for 180 seconds from the passage of the video laryngoscope through the central incisors | 
| The difficulty of intubation | The difficulty of intubation evaluated using a visual analog scale (VAS) (ranging from 0, meaning extremely easy, to 100, which is extremely difficult). | for 180 seconds from the passage of the video laryngoscope through the central incisors | 
| The first-pass success | The first-pass success ratio is calculated as the number of first-attempt successes over the number of intubation attempts. | for 360 seconds from the passage of the video laryngoscope through the central incisors | 
| The number of times the video laryngoscope is withdrawn from mouth | The number of times the video laryngoscope is withdrawn from mouth then inserted again. | for 180 seconds from the passage of the video laryngoscope through the central incisors | 
| The number of times optimization maneuvers | The number of times optimization maneuvers are used in each attempt | for 180 seconds from the passage of the video laryngoscope through the central incisors | 
| The number of required external laryngeal manipulation | The number of required external laryngeal manipulation to improve the glottic view | for 180 seconds from the passage of the video laryngoscope through the central incisors | 
| The preferred device | The preferred device as rated by the participant after completing all intubation attempts | For 4 weeks from the start of study |