Comparison between GlideRite® rigid stylet and Parker Flex-It™ stylet to facilitate GlideScope intubation in simulated difficult intubation: a randomized controlled study

Background: The GlideScope (R) videolaryngoscope (GVL) is widely used in patients with difficult airways and provides a good glottic view. However, the acute angle of the blade can make insertion and advancement of an endotracheal tube (ETT) more difficult than direct laryngoscopy, and the use of a stylet is recommended. This randomized controlled trial compared Parker Flex-It (TM) stylet (PFS) with GlideRite (R) rigid stylet (GRS) to facilitate intubation with the GVL in simulated difficult intubations. Methods: Fifty-four patients were randomly allocated to undergo GVL intubation using either GRS (GRS group) or PFS (PFS group). The total intubation time (TIT), 100-mm visual analog scale (VAS) for ease of intubation, success rate at the first attempt, use of laryngeal manipulation, tube advancement rate by assistant, and complications were recorded. Results: There was no significant difference between the GRS and PFS groups regarding TIT (50.3 +/- 12.0 s in the GRS group and 57.8 +/- 18.8 s in the PFS group, P = 0.108). However, intubation was more difficult in the PFS group than in the GRS group according to VAS score (P = 0.011). Cases in which the ETT was advanced from the stylet by an assistant, were more frequent in the GRS group than in the PFS group (P = 0.002). The overall incidence of possible complications was not significantly different. Conclusions: In patients with a simulated difficult airway, there was no difference in TIT using either the PFS or GRS. However, endotracheal intubation with PFS is more difficult to perform than GRS.