Determination of the optimal stylet strategy for the c-mac®videolaryngoscope

Abstract

The C-MAC (R) videolaryngoscope is a novel intubation device that incorporates a camera system at the end of its blade, thereby facilitating obtaining a view of the glottis without alignment of the oral, pharyngeal and tracheal axes. It retains the traditional Macintosh blade shape and can be used as a direct or indirect laryngoscope. We wished to determine the optimal stylet strategy for use with the C-MAC. Ten anaesthetists were allowed up to three attempts to intubate the trachea in one easy and three progressively more difficult laryngoscopy scenarios in a SimMan (R) manikin with four tracheal tube stylet strategies: no stylet; stylet; directional stylet (Parker Flex-It (TM)); and hockey-stick stylet. The use of a stylet conferred no advantage in the easy laryngoscopy scenario. In the difficult scenarios, the directional and hockey-stick stylets performed best. In the most difficult scenario, the median (IQR [range])duration of the successful intubation attempt was lowest with the hockey-stick stylet; 18 s (15-22 [12-43])s, highest with the unstyletted tracheal tube; 60 s (60-60 [60, 60])s and styletted tracheal tube 60 s (29-60 [18-60])s, and intermediate with the directional stylet 21 s (15-60 [8-60])s. The use of a stylet alone does not confer benefit in the setting of easy laryngoscopy. However, in more difficult laryngoscopy scenarios, the C-MAC videolaryngoscope performs best when used with a stylet that angulates the distal tracheal tube. The hockey-stick stylet configuration performed best in the scenarios tested.