Satin slip stylet

At each patient position, participants attempted ETI using three types of intubation techniques: direct laryngoscopy using MCL and blind intubation with two different supraglottic airway devices (SADs). The MCL had a size-4 curved blade, and direct laryngoscopy was performed using with a Satin Slip Stylet (Mallinckrodt Medical, St. Louis, MO, USA). Two types of SADs were used for blind intubation in this study: a size-4 i-gel (Intersurgical, Berkshire, UK) and a size-4 LMF. A 7.0-mm internal diameter endotracheal tube (ETT) (Mallinckrodt Hi-Lo Oral/Nasal Tracheal Tube Cuffed Murphy Eye; Covidien, Dublin, Ireland) was used for direct laryngoscopy, and a 6.0-mm internal diameter ETT of the LMF was used for blind intubation through SADs. Each ETT was lubricated by airway lubricant (Airway lubricant glycerol version; Laerdal Medical, Stavanger, Norway) before performing ETI.
We used an airway trainer manikin (AirSim Advance Combo Bronchi; TruCorp, Belfast, Northern Ireland) to perform ETI. The simulation airway setting was regulated by cervical immobilization using a cervical collar (Perfit ACE; Ambu, Ballerup, Denmark). The stretcher-level patient position was simulated using a 91-cm-height of an ambulance stretcher (stretcher, 189×58×91 cm; Sungwoo Motors, Eumseong, South Korea).

One direct laryngoscope and 3 SADs were used in this study. A direct laryngoscope is the MCL, which has a size 4 curved blade with a Satin Slip Stylet (Mallinckrodt Medical, St. Louis, MO, USA). We also performed intubation using SAD size 4 i-gel (Intersurgical, Berkshire, UK), size 3.5 air-Q (Cookgas LLC; Mercury Medical, Clearwater, FL, USA) and size 4 LMA Fastrach. We used a Laerdal airway management trainer (Laerdal, Stavanger, Norway) for performing intubations in this study. A 7.0-mm internal diameter cuffed polyvinyl chloride (PVC) tube (Portex, Keene, NH, USA) was used for blind tracheal intubation by each group [7 (link)]. The endotracheal tube (ETT) was lubricated with water-based jelly before insertion.