Comparison of direct versus video-laryngoscopy during simulated pediatric cervical spine immobilization

Introduction
Endotracheal intubation is a standard airway management in many life-threatening conditions. However, in the case of immobilization of the cervical spine, it is impossible to perform "sniffing position" during intubation, and visualization of the glot¬tis may be difficult or impossible to perform.

Purpose
The aim of the study was to compare video-laryngoscopy and direct laryngoscopy during a simulated immobilization of the cervical spine in a child.

Material and methods
The study was designed as a randomized, crossover, simulation study. The study involved 56 junior doctors who performed intubation using a laryngoscope with a Miller blade (MIL) or GlideScope video-laryngoscopy (GLS). Intubation was performed in two scenarios: normal airways (Scenario A) and the immobilization of the cervical spine by a collar and manual stabilization (Scenario B).

Results
In scenario A, the median duration of intubation using MIL was 20.5 (IQR 18-27) s, and for the GLS - 18.5 (IQR 17-25) s (p = 0.095). The effectiveness of the first attempt intubation was 62.5% for the MIL and 75% for the GLS (p = 0.034). During the scenario B, the median duration of intubation was varied and amounted to 37.5 (IQR 33-49.5) s for the MIL and 30 (IQR 25-37) s for GLS (p = 0.011), and the efficiency of intubation was 23.2% for MIL and 57.1% for the GLS (p < 0.001).

Conclusions
In simulation study, it has been demonstrated that the use of the stabilization of the cervical spine significantly reduces the effectiveness of endotracheal intubation. Persons participating in the study performed intubation using GlideScope video-laryngoscopy with more efficiency at first attempt intubation and in less time. Further research is needed to confirm the results.