Comparison of UESCOPE VL 400, I-VIEW, Airtraq Videolaryngoscopes and Macintosh Laryngoscope for Tracheal Intubation in Simulated Out-of-Hospital Conditions: A Randomized Crossover Manikin Study

Pre-study preparation All participants attended a 30-minute lecture on laryngoscope construction, principles of usage, anatomical structure of the airways, and intubation techniques. Following the lecture, the instructor demonstrated proper intubation using each of the four laryngoscopes that were being tested. Next, the students participated in a supervised workshop where they had the opportunity to intubate a mannequin placed on an operating table at an optimal height using each of the tested laryngoscopes with and without a stylet. One month later, 30 students participated in the actual study.

Simulation model To create simulated out-of-hospital conditions, a certified airway training manikin (Laerdal Airway Management Trainer Stavanger Norway of universal difficulty) was placed in a neutral position at floor level.

The trial tested three unchanneled videolaryngoscopes: UESCOPE VL 400 (Zhejiang UE Medical Corp. Zhejiang, China), I-View™ VL (Intersurgical Ltd, Wokingham, Berkshire, UK), Airtraq sp ® (Prodol Meditec S.A, Vizcaya, Spain), and a Macintosh laryngoscope (HEINE Optotechnik GmbH & Co. KG, Gilch-ing, Germany) (see Fig. 1).

Each participant performed eight intubations on the manikin using all four devices. The intubation order was randomized using a blocked randomization strategy generated by the Randomizer Program (randomizer.org). A sealed opaque envelope was used to determine the order in which the laryngoscopes were used, and whether the tube was with or without a stylet.

After each intubation, there was a minimum 10-minute pause before the next one. The subject then proceeded to the next intubation with the randomly selected laryngoscope, with the tube and stylet as determined by the sealed envelope.