Direct versus indirect laryngoscopic visualization in human endotracheal intubation: a tool for virtual anesthesia...

When performing the ABC's of care for the trauma patient, airway management is of paramount importance. Management of the airway is often difficult because medical personnel caring for the patient do not commonly intubate patients or manage airways. To accomplish endotracheal intubation, a direct line of sight must be accomplished through the mouth, pharynx and larynx to the glottic opening. This is anatomically challenging in patients with a small mouth, large tongue, lack of cervical mobility, cervical trauma, protruding incisors or small mandible. This investigation compares indirect laryngoscopy, which allows the laryngoscopist to "see around the corner" during intubation, to standard direct laryngoscopy. This indirect view is a virtual view of the airway accomplished by projecting the view from an image device on the end of the laryngoscope to a monitor viewed by the laryngoscopist. The virtual (indirect) laryngoscopy improved the view of the glottic opening by an average 1.28 (p<0.001) Cormack-Lehane grades, consistant with existing literature. Indirect laryngoscopy results in improved glottic visualization compared to direct laryngoscopy. This difference will prove critically important for medical personnel who infrequently intubate and for students learning intubation skills in a clinical setting. The results of our study confirm the value of videolaryngoscopy as a standard method for hands-on airway management training of medical personnel. Indirect "virtual" laryngoscopy is an advanced technology method which will advance the development of teleanesthesiology practice. Videolaryngoscopy is an enabling technology for development of remote telementoring of trainee intubation skills curricula using video enabled distributed learning systems. This research was conducted following an approved University of Nebraska Medical Center institutional review board protocol.