Does the Use of a Videolaryngoscope Modifies Anesthetic Induction ?

Study Overview
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Brief Summary
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Videolaryngoscopes become widely used. The aim of this study is to compare anesthetic induction when patients are tracheally intubated using a MacGraph Mac videolaryngoscope or a conventional MacIntosh laryngoscope. Tracheal intubation induces a nociceptive stimulation. Hypothesis is that the use of a videolaryngoscope induces a less pronounced nociceptive stimulation and, consequently, that it modifies the anesthetic drugs requirement. .

Detailed Description
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All patients will received a standardized anesthetic procedure : combined closed-loop anesthesia system using bispectral index as control variable and two proportional-differential control algorithms, a propofol and a remifentanil target-controlled infusion system. The effectiveness of such a closed-loop anesthesia system has been demonstrated in a prospective, randomized study. Patients will be randomized in two groups : intubation using a conventional MacIntosh laryngoscope or intubation using a videolaryngoscope. If our hypothesis is confirmed, the required concentration of remifentanil, an opioid agent, will be reduced in the group using a videolaryngoscope.

Official Title
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Does the Use of a Videolaryngoscope Modifies Anesthetic Induction ?

Conditions
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Tracheal Intubation

Intervention / Treatment
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* Procedure: Tracheal intubation
* Drug: Propofol and remifentanil anesthesia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patient scheduled for a general anesthesia with orotracheal intubation Exclusion Criteria: predictable risk of difficult mask ventilation or of difficult tracheal intubation necessity of a rapid sequence induction contra-indication to the use of the automated administration of propofol and of remifentanil contra-indication to the use of atracurium Otolaryngology, thoracic surgery, or intracranial surgery

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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No

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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Macintosh laryngoscope<br>Tracheal intubation will be performed using a Macintosh laryngoscope. All patients will received propofol and remifentanil anesthesia. | Procedure: Tracheal intubation<br>* Tracheal intubation will be performed using a Macintosh laryngoscope or a McGrath Mac videolaryngoscope<br>Drug: Propofol and remifentanil anesthesia<br>* The standardized anesthetic procedure used a closed-loop anesthesia system with bispectral index as control variable and with two proportional-differential control algorithms, one for propofol target-controlled infusion system and one for remifentanil target-controlled infusion system.<br>|
| Experimental: McGrath Mac videolaryngoscope<br>Tracheal intubation will be performed using a McGrath Mac videolaryngoscope. All patients will received propofol and remifentanil anesthesia. | Procedure: Tracheal intubation<br>* Tracheal intubation will be performed using a Macintosh laryngoscope or a McGrath Mac videolaryngoscope<br>Drug: Propofol and remifentanil anesthesia<br>* The standardized anesthetic procedure used a closed-loop anesthesia system with bispectral index as control variable and with two proportional-differential control algorithms, one for propofol target-controlled infusion system and one for remifentanil target-controlled infusion system.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Required dose of opioid to counteract nociceptive stimulation | Tracheal intubation induces a nociceptive stimulation. Hypothesis is that the use of a videolaryngoscope induces a less pronounced nociceptive stimulation and, consequently, that the required maximal concentration of remifentanil is lower than when a standard laryngoscope is used. | 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Characteristics of anesthesia | Peak concentration of propofol | one hour | 
| Characteristics of anesthesia | doses of propofol and of remifentanil (from beginning of the induction to 5 minutes after tracheal intubation) | one hour | 
| Characteristics of anesthesia | values of bispectral index (from beginning of the induction to 5 minutes after tracheal intubation) | one hour | 
| Characteristics of tracheal intubation | time to obtain the first capnogram | one hour | 
| Characteristics of tracheal intubation | visualization of the glottis (score of Cormak and Lehane modified by Yentis, POGO score | one hour | 
| Characteristics of tracheal intubation | use of alternative techniques for intubation | one hour | 
| Characteristics of tracheal intubation | esophageal intubation | one hour | 
| Characteristics of tracheal intubation | incidence of arterial oxygen desaturation (SpO2 <92%) | one hour | 
| Characteristics of tracheal intubation | hemodynamic effects of induction and tracheal intubation | one hour | 
| Complications of intubation | Throat pain and hoarseness | one day | 
| Ergonomic evaluation of the device | questionnaire Qusi | one hour |