In difficult airway situation, fiberoptic-guided endotracheal intubation through laryngeal mask airway(LMA) is one of option. Aintree catheter is a device to help change LMA to endotracheal tube, but it needs complex and multiple process. Long endotracheal tube can solve this problem of Aintree catheter. The purpose of this study is proving the efficacy of long endotracheal tube compared to Aintree cathter in fiberoptic-guided intubation through LMA.

In difficult aiway situation, fiberoptic-guided endotracheal intubation through laryngeal mask airway(LMA) is one of option according to Difficult intubation guidelines. First, insert LMA and insert fiberoptic through LMA. Second, insert endotracheal tube using fiberoptic as a guide. This process has several problem. Removal of LMA is impossible, so there is a risk of dislodging of endotracheal tube.

Aintree catheter is developed to this problem. Insert Aintree catheter through LMA using fiberoptic, and remove LMA, finally insert endotracheal tube throug Aintree catheter. But the problem of this method is that the whole process is complex and takes long time. And there is a risk of impeding of endotracheal tube at glottis level because the difference of diameters between endotracheal tube and aintree catheter.

Long endotracheal tube could solve the problems mentioned above. Through LMA, insert endotracheal tube using fiberoptic as a guide. Tube is long enough to remove LMA without a risk of dislodging. And after removal of LMA, tube can be cut for optimizing length.

So the purpose of this study is comparing the efficacy of Aintree catheter method and Long tube method in manikin.

Inclusion Criteria:

• Residents of Anesthesiology
• Who has less than 10 times of experience of fiberoptic intubation

Exclusion Criteria:

• Who has more than 10 times of experience of fiberoptic intubation
• Who deny participating in the study

only for personally requested