Infrared Transillumination of the Front of the Neck

Study Overview
=================
Brief Summary
-----------------
Infrared light is applied to the front of the neck of patients for awake flexible optical intubation. The infrared light can be detected by the camera at the tip of the flexible video-bronchoscope. The flexible scope is introduced into the trachea with or without the aid of the blinking infra red light and the ease of placement of the flexible scope is studied.

Detailed Description
-----------------
The investigators study patients for anaesthesia who will need endotracheal intubation and in whom the intubation is predicted to become difficult so that an awake flexible-video-scope-guided intubation is chosen. Infrared light is applied to the front of the neck of patients for awake flexible optical intubation. The infrared light can be detected by the camera at the tip of the flexible video-bronchoscope. The flexible scope is introduced into the trachea with or without the aid of the blinking infra red light and the ease of placement of the flexible scope is studied.

Official Title
-----------------
Infrared Transillumination of the Front of the Neck as an Aid for Awake Intubation

Conditions
-----------------
Tracheal Intubation

Intervention / Treatment
-----------------
* Procedure: Tracheal intubation by endoscopy with flexible bronchoscope


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients scheduled for awake tracheal intubation over the insertion cord of a flexible video-trachea-bronchoscope. Exclusion Criteria: Age < 18 years Patients at high risk of aspiration of gastric content Patients with hypoxia, saturation < 90 % on ambient air Patients with audible stridor at rest American Society of Anesthesiology (ASA) physical class > 3 contraindication for trans-crico-thyoid-membrane puncture (cancer, infection on the site, severely coagulopathies, inability to identify the crico-thyroid membrane)

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

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

Accepts Healthy Volunteers
-----------------
No

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

Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Infrared guidance first<br>In this arm the infra red guidance is applied to the first passage of the flexible scope to the trachea. The second passage of the flexible scope is without the infrared light | Procedure: Tracheal intubation by endoscopy with flexible bronchoscope<br>* A blinking infrared light source is placed on the anterior neck at the level of the cricothyroid membrane to serve as a guide to facilitate finding the way to the trachea<br>|
| Active Comparator: Infrared guidance last<br>In this arm NO infra red guidance is applied to the first passage of the flexible scope to the trachea. The second passage of the flexible scope is with the infrared light as guide | Procedure: Tracheal intubation by endoscopy with flexible bronchoscope<br>* A blinking infrared light source is placed on the anterior neck at the level of the cricothyroid membrane to serve as a guide to facilitate finding the way to the trachea<br>|

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

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fraction of cases where the blinking light is seen before the vocal cords are seen | The flexible scope is entered into the airway twice, . It is noted from watching the videos of the procedures if the blinking light or the vocal cords are seen first - | 1 day of the procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fraction of cases where the blinking light is seen from the teeth, the mouth, the pharynx and the larynx and the fra fraction of cases where the vocal cords are seen from the teeth, the mouth, the pharynx and the larynx | The flexible scope is entered into the airway twice, one time with and one time without the blinking light on the front of the neck. It is noted from watching the videos of the procedures if the blinking light or the vocal cords are seen first - and from which anatomical location it is seen. | 1 day of the procedure | 
| Time from the tip of the flexible scope passes the teeth until vocal cords are seen | Time measured from the tip of the flexible scope passes the teeth until the vocal cords are seen | 1 day of the procedure |