Tracheal intubation with videolaryngoscopes in patients with cervical spine immobilization: a randomized trial of the Airway Scope® and the GlideScope®

Abstract
The GlideScope® (Verathon Inc., Bothell, WA, USA) and Airway Scope® (Hoya Corp., Tokyo, Japan) have both been used for difficult airway management, including in patients with cervical spine pathology. The Airway Scope®'s disposable blade has a tube channel to guide tracheal tube insertion through the glottis. Our hypothesis is that this tube guidance system improves the ease of tracheal intubation compared with the GlideScope®, which does not have a tube guiding system. We tested this hypothesis in a randomized comparison of the two videolaryngoscopes in patients whose cervical spines were immobilized. Seventy consenting patients were randomized to have tracheal intubation with the GlideScope® (n=35) or the Airway Scope® (n=35). In all patients, we applied manual in-line stabilization of the cervical spine throughout airway management. All the airway procedures were carried out by two anaesthetists experienced in the use of both videolaryngoscopes. The tracheal intubation time was 34.2 (sd 25.1) s with the Airway Scope® compared with 71.9 (47.9) s with the GlideScope® (P® in 35 (100%) patients compared with 31 (88.6%) patients with the GlideScope® (P=0.114). Tracheal intubation was successful within 60 s in 33 (94.3%) patients with the Airway Scope® and 22 (62.9%) patients with the GlideScope® (P=0.003). These results suggest that the Airway Scope®'s tube guide system enables more rapid tracheal intubation compared with the GlideScope® in patients with cervical spine immobilization.