The usual intubation technique in the operating room is based on direct laryngoscopy, using a standard Macintosh laryngoscope. However, this skill is not easy to acquire and requires adecuate training. Videolaryngoscopes are becoming a widely accepted airway management technique. because offer better view of the glottis and are easy to use. In addition, indirect laryngoscopes are useful for tracheal intubation by novice operators because of the feedback that supervisors can offer during intubation. The goal of this clinical trial is to learn which intubation technique performed by residents of anesthesia in the operating room is better. The main questions it aims to answer are: * Which intubation technique is more effective for achieving first-attempt intubation? * Which intubation technique results in fewer complications? Researchers will compare both intubation techniques performed by anesthesia residents in the operating room in adult anesthesia cases.