IRCT201403069585N4 IRCT 2014-05-27 Kerman University of Medical Sciences Comparison between jaw thrust maneuver and transillumination in intubation by flexible fiberoptic laryngoscope Comparison of intubation time of jaw thrust maneuver versus transillumination in intubation by flexible fiberoptic laryngoscope in patients with elective surgeries. 2014-03-21 anticipated 90 Complete https://irct.ir/trial/10161 interventional Randomization: Randomized, Blinding: Not blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment, Other design features: The plan of anesthesia is explained for patients and after obtaining informed consent, they will be monitored completely, blood pressure is measured noninvasive and PETCO2 is measured by mainstream method. All intubation will be performed by a same person. The method of anesthesia for all of them is similar. Randomization is done by draw. N/A Endotracheal Intubation. Intervention 1: In control group: oral intubation is performed by flexible fiberoptic laryngoscope made by Olympus company using jaw thrust maneuver and pulling tongue. Intervention 2: Intervention in second group: oral intubation is performed by flexible fiberoptic laryngoscope made by Olympus company using transillumination of anterior neck without inspection through bronchoscope. Intervention 3: Intervention in first group: oral intubation is performed by flexible fiberoptic laryngoscope made by Olympus company using transillumination of anterior neck with inspection through bronchoscope.