Stylet Angle for McGrath Videolaryngoscopy

The McGrath videolaryngoscope (VL) provides excellent laryngoscopic views, but directing an endotracheal tube is not easy, so routine using of stylet is recommended. The goal of this study is to determine the appropriate angle of stylet by comparing time to intubation (TTI).

Inclusion Criteria:

• an American Society of Anesthesiologists physical status (ASA) 1 or 2

Exclusion Criteria:

• a suspected difficult airway (Mallampati score Ⅳ)
• known cervical spine injury
• required rapid sequence induction
• emergency operation