First-attempt awake tracheal intubation success rate using a hyperangulated unchannelled videolaryngoscope vs. a channelled videolaryngoscope in patients with anticipated difficult airway: a randomised controlled trial

Introduction

There is uncertainty about the optimal videolaryngoscope for awake tracheal intubation in patients with anticipated difficult airway. The use of channelled and unchannelled videolaryngoscopy has been reported, but there is a lack of evidence on which is the best option.

Methods

We conducted a randomised clinical trial to compare the efficacy of the C-MAC D-Blade® vs. Airtraq® in adult patients (aged ≥ 18 y) scheduled for elective or emergency surgery under general anaesthesia with anticipated difficult airway who required awake tracheal intubation under local anaesthesia and conscious sedation. The primary endpoint was the first-attempt tracheal intubation success rate. Secondary outcomes included the overall success rate; number of tracheal intubation attempts; Cormack and Lehane glottic view; level of difficulty (visual analogue score); patient discomfort (visual analogue score); and incidence of complications.

Results

Ninety patients (70/90 male (78%); mean (SD) age 65 (12) y) with anticipated difficult airways were randomly allocated to C-MAC D-Blade or Airtraq videolaryngoscopy. First-attempt successful tracheal intubation rate was higher in patients allocated to the C-MAC D-Blade group compared with those allocated to the Airtraq group (38/45 (84%) vs. 28/45 (62%), respectively; p = 0.006). The proportion of patients' tracheas that were intubated at the second and third attempt was 4/45 (9%) and 3/45 (7%) in those allocated to the C-MAC D-Blade group compared with 14/45 (31%) and 1/45 (2%) in those allocated to the Airtraq group (p = 0.006). There was no significant difference in overall tracheal intubation success rate (C-MAC D-Blade group 45/45 (100%) vs. Airtraq group 43/45 (96%), p = 0.494).

Discussion

In patients with anticipated difficult airway, first-attempt awake tracheal intubation success rate was higher with the C-MAC D-Blade compared with Airtraq laryngoscopy. No difference was found between the two videolaryngoscopes in overall tracheal intubation success rate.