The use in a combined way of two systems of intubation (Glidescope + aScope) would condition an increase in the success rate of endotracheal intubation maneuver compared to conventional isolated Glidescope use in patients with clinical criteria of difficult airway.

Worldwide, up to 600 patients are estimated to die annually as a result of the complications that occur during tracheal intubation The GlideScope® (videolaryngoscope) is used for endotracheal intubation in patients with difficult airway predictors, in this patients overall success intubation rate is 96%. but success intubation rate at first attempt is only 86%.

Despite this positive rates, due to high comorbidity when intubation fails, both failure rates (inverse of success rate) are impermissible. 14% failure at the first attempt intubation as well as 4% overall intubation failure.

in this study the investigators try to show that new procedure associating aScope® (disposable fiberscope) together with GlideScope® increases the success intubation rate of both ( overall and first attempt).

Inclusion Criteria:

• Patients programed for general anesthesia with endotracheal intubation required that presents one or both criteria of difficult airway predictors:
• criteria 1: Arne test >10 (Arne J,1998)
• criteria 2: Ratio between neck circumference and thyromental distance > 4. (Kim WH, 2011)

Exclusion Criteria:

• Patients with mouth opening which does not allow the introduction of video laryngoscope.
• Patients with indication of flexible fiberoptic intubation with awake patient.