The purpose of this study is to evaluate whether the McGrath® MAC video laryngoscope is equal or superior when compared to the Glidescope® Ranger and the Macintosh laryngoscope for novice users in a simulated airway manikin.

Investigators compared two portable video laryngoscopes (the GlidesScope® Ranger (Verathon Inc, Bothell, WA, USA) and the McGrath® MAC (Aircraft Medical Ltd, Edinburgh, UK)) and a German type Macintosh metal blade with a fiberoptic light. A blade size of 4 was used on all devices. All intubations using video laryngoscopes were performed according to the manufacturers' instructions. A specialised rigid stylet (the GlideRite®) was used with the Glidescope® and a flexible plastic stylet bent with a hockey stick curvature, was used with the McGrath® MAC and the Macintosh laryngoscope. A size 7.5 endotracheal tube (Mallinckrodt™ Hi-Lo Oral/Nasal Tracheal Tube Cuffed Murphy Eye, Covidien, Ireland) was used with all the laryngoscopes.

All participants were randomly divided into 3 device groups. Each group was allowed to attempt to perform endotracheal intubation five more times using the Laerdal® Airway Management Trainer (Laerdal Medical Korea Ltd., Seoul, Korea) with the normal airway setting. After completing the normal airway session, the participants performed another five attempts with the neck immobilisation setting using a neck collar.

The sequence in which the three devices were used was randomly assigned, and all participants performed the same sequence at intervals of five weeks during the study.

Inclusion Criteria:

• Medical students without previous experience of intubation

Exclusion Criteria:

• Heart, wrist, or low back disease or who were pregnant were excluded