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Video laryngoscopes and optical stylets for airway management for anesthesia in adults

Richard M Cooper, MD, B.Sc. M.Sc., FRCPC
Matteo Parotto, MD, PhD
Section Editor
Carin A Hagberg, MD
Deputy Editor
Marianna Crowley, MD


Video laryngoscopes (VLs) and optical stylets (OSs) are rigid devices that allow indirect laryngoscopy, or visualization of the vocal cords and related airway structures without a direct line of sight.

VLs are fundamentally retraction devices with illumination and optical elements. In contrast, OSs provide little retraction. They are tubular devices that fit inside the tracheal tube and convey an image using either a fiberoptic bundle or a video camera.

Optical indirect laryngoscopes use prisms, lenses, and mirrors rather than electronic components. The only available example of such a device is the Airtraq, which for the sake of simplicity we will consider a VL.

This topic will discuss the various types of VLs and OSs, the techniques used for endotracheal intubation with these devices in adults, and airway management outcomes with their use. Direct laryngoscopy, flexible scope intubation, use of supraglottic airways in anesthesia, and videolaryngoscopy in children, are discussed separately. (See "Direct laryngoscopy and endotracheal intubation in adults" and "Flexible scope intubation for anesthesia" and "Supraglottic devices (including laryngeal mask airways) for airway management for anesthesia in adults" and "Devices for difficult endotracheal intubation in children", section on 'Video laryngoscope'.)


The primary advantage of indirect laryngoscopy devices is the ability to look around corners, enabling the operator to see what is not within the line of sight, using fiberoptic bundles, video cameras, or prisms. Other advantages include the option for other clinicians to simultaneously see what the operator sees, which creates opportunity for collaboration and teaching, and the fact that almost all of these devices enlarge the image. Some devices allow for recording, which is useful for clinical documentation, quality improvement, and teaching. They also create an opportunity for remote supervision by a more experienced airway manager, which may be beneficial in rural hospitals and during prehospital emergency airway management [1].


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Literature review current through: Jul 2017. | This topic last updated: May 16, 2017.
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