Introduction
Endotracheal intubation (ETI) in the emergency department (ED) is often complicated by several unique factors relating to the critically ill patient population and the environment. These factors can contribute to difficultly in performing ETI and, therefore, multiple attempts may be required to secure the patient's airway. Multiple ETI attempts have been associated with several adverse events including hypoxia, brain damage, or even death (1). Video laryngoscopy is one tool for assisting in airway management and has been advocated for in multiple populations, including in emergency airway management 2, 3. The market currently offers a wide variety of different video devices. The GlideScope (Verathon Medical, Burnaby, British Columbia, Canada) and the C-MAC (Karl Storz Corp, Tuttlingen, Germany) are two frequently used in the ED (4).
Awake upright intubation (AUI) is another modality in securing airways that can reduce many of the risks associated with traditional intubation 5, 6, 7. AUI allows patients to remain in a seated, rather than a supine, position and eliminates the need for sedation and paralysis often used in traditional ETI. AUI is often performed with a flexible fiber optic scope. However, this is not feasible in many EDs due to the lack of emergent access to fiber optics and a lack of familiarity with the technique.
A recent study compared the flexible fiber optic approach with one using the GlideScope in awake upright intubation (8). Silverton et al.’s study found the two to be comparable, however, there are technical aspects of the GlideScope that raise the question as to whether this technique is transferable to other forms of video laryngoscopy. The GlideScope makes use of a unique stylet and hyperacute angulated blade (9). These modifications require an adjustment in technique during ETI from classic direct laryngoscopy. Alternately, the C-MAC video laryngoscope allows for the benefits of video laryngoscopy, while using the same techniques used in classic direct laryngoscopy, displacing the soft tissue of the oropharynx in a manner similar to a classic Macintosh laryngoscopic blade 9, 10. The GlideScope and C-MAC are commonly used in the ED for ETI, however, no study has compared the GlideScope and C-MAC devices in the setting of awake upright laryngoscopy.
We sought to compare the quality of glottic visualization and time intervals view between C-MAC and GlideScope video laryngoscopes in awake upright patients.