The Clarus Video System and Direct Laryngoscope for Rapid Sequence Induction Intubation With Cricoid Pressure

Study Overview
=================
Brief Summary
-----------------
During an emergency endotracheal intubation, rapid sequence induction intubation with cricoid pressure is frequently implemented to prevent aspiration pneumonia. When properly applied, cricoid pressure may not affect glottic view during endotracheal intubation with either a direct laryngoscope or a video laryngoscope. However, the application of cricoid pressure is likely to prolong the intubation time. Limited mouth opening or vulnerable teeth, which often accompany the patients requiring emergency intubation, are the two common factors to deter the intubators from using a laryngoscopic device. Besides, the blade of a laryngoscopic device is often too bulky for a narrow mouth opening, and the blade always bears a level force on upper incisors while the intubator is lifting epiglottis during intubation, which is liable to tooth fracture. In this prospective randomized study, the investigators compare the use of the Clarus Video System and that of direct laryngoscope (Macintosh Laryngoscope) in patients undergoing endotracheal intubation in simulated rapid sequence induction intubation for the primary goals of the first attempt success rate and intubation time.

Official Title
-----------------
The Clarus Video System (Trachway) and Direct Laryngoscope for Endotracheal Intubation With Cricoid Pressure in Simulated Rapid Sequence Induction Intubation: A Prospective Randomized Controlled Trial

Conditions
-----------------
Intubation, Intratracheal, Laryngoscopes, Anesthesia, General

Intervention / Treatment
-----------------
* Device: the Clarus Video System as a video stylet
* Device: the Clarus Video System as a lightwand
* Device: direct laryngoscope


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Older than 20 years of age Scheduled for elective surgery under general anesthesia Exclusion Criteria: BMI (Body Mass Index) > 35 kg/m2 Interincisor distance < 3 cm Poor dentition Upper airway tumor Limited neck mobility Pregnancy History of difficult tracheal intubation

Ages Eligible for Study
-----------------
Minimum Age: 20 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: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intubation with the Clarus Video System as a video stylet<br> | Device: the Clarus Video System as a video stylet<br>* video-guided intubation<br>* Other names: Trachway as a video stylet;|
| Experimental: Intubation with the Clarus Video System as a lightwand<br> | Device: the Clarus Video System as a lightwand<br>* The endotracheal tube will be initially guided into larynx in the dimly lit operating room by a bright glow moving in the anterior soft tissue of the neck and finally by the image of the trachea rings on the video screen.<br>* Other names: Trachway as a lightwand;|
| Active Comparator: Intubation with direct laryngoscope<br> | Device: direct laryngoscope<br>* Macintosh laryngoscope size 3<br>|

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

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The first attempt success rate |  | After intubation immediately | 
| Intubation time | Intubation time was counted from the inserting the device into the patient's mouth to viewing the endotracheal tube into the trachea. | After intubation immediately | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood pressure | Measure blood pressure in millimeter of mercury by non-invasive blood pressure before induction, 1 minute after intubation, and 5 minutes after intubation | 1 minute and 5 minutes after intubation | 
| Heart rate | Measure heart rate in beats per minute by electrocardiography monitor before induction, 1 minute after intubation, and 5 minutes after intubation | 1 minute and 5 minutes after intubation | 
| Sore throat | Documented by a blinded observer on the next day. Sore throat was graded according to numerical rating scale (NRS): none, NRS = 0; mild, NRS = 1-3; moderate, NRS = 4-6; severe, NRS = 7-10. | On postoperative day 1 | 
| Mucosal injury | Documented by a blinded observer on the next day. Yes is defined as any oral mucosal lesion reported by participants. | On postoperative day 1 |