The Effect of The Use of a Videolaryngoscope and/or Stylet on Intubation Time in Obese Patients

Study Overview
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Brief Summary
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Although many researchers would agree that obesity per se is not a risk factor for difficult intubation, there are many well known obesity-related challenges in airway management including difficulty with mask ventilation, more frequent and rapid oxygen desaturation, increased oxygen consumption, and increased sensitivity to the respiratory depressant effects of anesthetic and analgesic drugs. Hence, in these conditions, rapid and nontraumatic intubation gain higher interest. There is controversy about using videoaryngoscopy (VL) in obese patients in these difficult situations. The primary aim of this study is to compare, in terms of intubation time, VL,VL plus stylet and direct-laryngoscopy(DL) plus stylet combination with DL alone in obese patients.

Detailed Description
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Patients who will be scheduled for surgeries requiring endotracheal intubation, with a body mass index (BMI) more than 30 kg/m2, will be included to this study. During preanesthetic visit (performed by an anesthesiologist not involved in this study) history of difficult intubation, measurement of common predictive indices for difficult intubation (BMI, thyromental distance, neck circumference, Mallampati grade, interincisal [or intergingival] distances), and evaluation of status of dentition and neck movement will be noted. In the operating room, all patients will be connected to standard monitoring devices. Anesthesia induction will be carried out according to our hospital obese patient anesthesia management protocol. Then, after induction of anesthesia, the patients will be intubated one of four pre-defined protocols that will be determined via randomization during a preanesthetic visit by a person who is unfamiliar with the research protocol. Primary hypothesis of this study is; using a video-laryngoscope plus stylet will reduce the time required to achieve successful tracheal intubation in obese patients.

Official Title
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The Effect of The Use of a Videolaryngoscope and/or Stylet on Intubation Time in Obese Patients: A Randomized Clinical Trial

Conditions
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Intubation Time

Intervention / Treatment
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* Procedure: Endotracheal Tube Alone
* Procedure: Endotracheal Tube+ Stylet
* Procedure: Endotracheal Tube + Video-laryngoscope
* Procedure: Endotracheal tube + stylet with Video-laryngoscope


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with a documented body mass index (BMI) of ≥ 30. Patients scheduled to undergo inpatient surgery procedures under general anesthesia. Willingness and ability to sign an informed consent document 18 - 80 years of age Exclusion Criteria: Patients who are deemed to be such a significant of an airway risk that they necessitate awake fiberoptic intubation Patients with a history of facial abnormalities, oral-pharyngeal cancer, or reconstructive surgery Emergency surgeries Pregnancy Any other conditions or use of any medication which may interfere with the conduct of the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Group DL<br>The control group consists of intubating the trachea with an endotracheal tube alone (without stylet). | Procedure: Endotracheal Tube Alone<br>* Intubating the trachea with an endotracheal tube alone ( without stylet).<br>|
| Experimental: Group DLS<br>The Experimental group consists of intubating the trachea with an endotracheal tube + stylet. | Procedure: Endotracheal Tube+ Stylet<br>* Intubating the trachea with an endotracheal tube + stylet.<br>|
| Experimental: Group VL<br>The Experimental consists of intubating the trachea with an endotracheal tube + Video-laryngoscope | Procedure: Endotracheal Tube + Video-laryngoscope<br>* Intubating the trachea with an endotracheal tube + Video- laryngoscope<br>|
| Experimental: Group VLS<br>The Experimental consists of intubating the trachea with an endotracheal tube + stylet + Video-laryngoscope | Procedure: Endotracheal tube + stylet with Video-laryngoscope<br>* Intubating the trachea with an endotracheal tube + stylet + Video-laryngoscope<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intubation Time Using a Stop Watch | The timing measurements will begin once the laryngoscope blade will be placed in the patient's mouth and ended when an end-tidal CO2 tracing will be detected. | Up to 3 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart Rate | Before induction, after induction, after intubation, after intubation at 1st minute, 2nd minute, and 3rd minute | Before induction to 3 min after intubation | 
| Mean Arterial Pressure: | Before induction, after induction, after intubation, after intubation at 1st minute, 2nd minute, and 3rd minute | Before induction to 3 min after intubation | 
| Saturation | Before induction, after induction, after intubation, after intubation at 1st minute, 2nd minute, and 3rd minute | Before induction to 3 min after intubation | 
| Incidence of severe complications following intubation | Hypoxia, collapse, cardiac arrest, death. | During intubation to 3 min after intubation | 
| Glottis View Using the Cormack Lehane Score | Cormack Lehane score classification Grade 1: Most of the glottis is visible Grade 2: At best almost half of the glottis is seen, at worst only the posterior tip of the arytenoids is seen Grade 3: Only the epiglottis is visible Grade 4: No laryngeal structures are visible | Up to 1 minute | 
| Glottis View Using the POGO Score | the POGO score evaluate the glottic view during tracheal intubation using a classification of 1/2/3/4 and a score of 0% to 100%, respectively. The POGO score denote visualization of the entire glottic opening from the anterior commissure to the posterior cartilages, and a score of 0% denotes inability to visualize any part of the glottic opening. | Up to 1 minute | 
| Number of intubation attempts | An intubation attempt will be defined as the insertion of the laryngoscope blade into the mouth of the patient, regardless of whether an attempt will be made to insert a tracheal tube. More than 5 attempts or 120 s will be regarded as a failure of intubation. | Up to postinduction 120 second | 
| Ease of Intubation | Subjective evaluation of the anesthesiologist, rated as (1) very easy, (2) easy, (3) moderate, (4) difficult, and (5) impossible. | Up to 1 minute | 
| Complications related to intubation | A postoperative follow-up assessment will be performed approximately 4 hr after surgery by a co-investigator blinded to the intubation device to evaluate the presence and severity of sore throat, any changes in voice, trauma to the lip, tongue, gum, or teeth. | postoperative 4th hour | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Obese Patients, Stylet Procedures, Video Laryngoscope, First-attempt intubation