A comparison of the new paediatric Glidescope® Cobalt Videolaryngoscope and the conventional laryngoscope in simulated normal and difficult intubation conditions
Authors: Weale N.K. , Bayley G.L. , Nolan J. , Sale S.M. , White M.C. 
Published: June 2009

Introduction:  Intubation is the core skill of every anaesthetist [1]. The Royal College of Anaesthetists has expressed concern over the apparent increase in airway problems. The Glidescope® can improve laryngeal view [2,3] in adults but not necessarily the time taken to intubation [3,4]. A new paediatric Glidescope® (GVL) became available in October 2008. Instead of the previous reusable version, GVL® small (weight range 1.5–20 kg) there are now two new disposable blades, GVL® 1 (<3.6kg) and GVL® 2 (1.8–10 kg) for use with the ultraportable Cobalt videobaton1–2. Disposable equipment is preferable as it reduces the risk of infection transmission. We aimed to compare the GVL® 2 with conventional laryngoscopy in a paediatric simulator BabySIM (METI) under both normal and difficult airway conditions. We hypothesised the new Glidescope® would perform as well as the conventional laryngoscope.

Methods:  Following ethics committee approval and informed consent, subjects were asked to perform four intubations in random order; two under normal and two under difficult airway conditions. For each condition, intubation was performed with a conventional laryngoscope (Miller blade) and a GVL® 2. The primary outcome was time to intubation, defined as time from picking up the laryngoscope until first successful inflation of the lungs. A visual analogue scale (VAS) was used to assess the laryngoscopes for field of view, ease of use, willingness to use in an emergency and overall satisfaction. Results were analysed using a paired t‐test.

Results:  Twenty eight anaesthetists were recruited (18 consultants, 10 trainees). Thirteen had no previous experience with the Glidescope® and 15 had used it less than10 times. Results are shown in Table 1. There was no statistical difference in the time taken for successful intubation between the conventional laryngoscope and Glidescope® although there was a trend towards a longer intubation time with the Glidescope®. Time to successful laryngoscopy was significantly longer for the difficult airway compared to the normal airway with both conventional laryngoscopy (P = 0.001) and the Glidescope® (P = 0.002).

  Time to successful intubation and results of VAS

Time to intubation (s) Mean (SD)
VAS (0–10) evaluation of laryngoscopes Median (IQR)

Normal
Difficult
Field of view
Ease of use
Emergency use
Overall

Conventional
26.3 (11.1)
45.2 (27.5)
8 (6–9)
8 (7–9)
9 (8–10)
8 (8–9)

Gildescope®
30.3 (20.0)
50.9 (21.9)
7 (6–9)
8 (7–9)
6 (5–7)
7 (6–8)

Discussion:  Successful intubation of our simulator manikin under difficult airway conditions was prolonged with both laryngoscopes when compared to normal conditions, suggesting that BabySIM is a useful model for difficult intubation. The Glidescope® performed as well as the conventional laryngoscope however it did not reduce the time to intubation, which is similar to results in adult simulators [3]. Our anaesthetists indicated a preference for conventional laryngoscopy in the emergency setting. This is likely to be due to familiarity with equipment.

Conclusion:  The Glidescope® performs as well as conventional laryngoscopy for intubation of the BabySIM manikin in both the normal and simulated difficult airway setting.