Protection afforded by respirators when performing endotracheal intubation using a direct laryngoscope, GlideScope®, and i-gel® device: A randomized trial
(a) Cup-type respirator, which is preformed to a cup shape. (b) Fold-type respirator, which is flexible and free-folded. (c) Macintosh laryngoscope, which has a size 4 curved blade with a Satin Slip stylet. (d) GlideScope® with a GlideRite rigid stylet. (e) I-gel® airway device.