Fiberoptic intubation is an important method for anesthesiologists to deal with difficult airways, but its operation is difficult and requires repeated practice. Fiberoptic intubation is performed in two steps. First, the anesthesiologist holds the bronchoscope and exposes the base of the tongue, the epiglottis, and the glottis successively according to the front camera of the bronchoscope. Through the glottis, the main trachea is exposed to the carina. This process is visual and the anesthesiologist can see the main tissue structure directly. Then, the endotracheal catheter enters the endotracheal along the bronchoscope, and the process of endotracheal catheter entry is not visual.

In clinical work, it was found that the tracheal catheter was easily blocked when it passed through the glottis, and it was necessary to adjust the position of the tracheal catheter for several times before the tracheal catheter could be sent into the tracheal tube, which was easy to cause throat injury in the process. At present, relevant studies are mainly focused on the first step of bronchoscopic intubation, how to quickly expose the glottis and complete the bronchoscopic guidance process. However, there is no clear mention of the situation of catatoning in the process of endotracheal catheter and how to solve the problem of catatoning.

According to the inclusion and exclusion criteria，collecting the data of participants who undergone fiberoptic intubation. The observer analysis the safety and efficiency of fiberoptic intubation.

Inclusion Criteria:

1.American Society of Anesthesiologists 1~2

2.18-60 year

3.Adult patients requiring general anesthesia for orotracheal intubation

Exclusion Criteria:

1. Limited mouth opening
2. limited movement of temporomandibular joint
3. abnormal glottic anatomy
4. polyps of vocal cords

Patients in need of oral tube intubation and general anesthesia in our hospital for elective surgery