The Portable AirWay Scope Video Laryngoscope

 

 

Ernst Zadrobilek, MD¹

 

¹Associate Professor of Anesthesia and Intensive Care, Chairman of the Austrian Working Group for Airway Management and Director of the Department of Anesthesia and Intensive Care, Empress Elisabeth Hospital of the City of Vienna, Vienna, Austria.

 

Address correspondence and comments to Ernst Zadrobilek.

 

Received from the Department of Anesthesia and Intensive Care, Empress Elisabeth Hospital of the City of Vienna, Vienna, Austria.

 

Key Words

Tracheal intubation: AirWay Scope video laryngoscope.
 

Published: June 20, 2007.

 

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The correct citation of this communiction of new equipment and techniques is:

Zadrobilek E. The portable AirWay Scope video laryngoscope. Internet Journal of Airway Management 4, 2006-2007.
Available from URL: http://www.adair.at/ijam/volume04/newequipment01/default.htm
Date accessed: month day, year.

 

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Last updated: February 12, 2008.

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Koyama and co-workers developed a new portable video laryngoscope, the AirWay Scope (AWS), in cooperation with the Pentax Corporation (Tokyo, Japan) for use with a dedicated (anatomically shaped) disposable laryngoscope blade (DLB). The AWS became commercially available in Japan during July 2006, and in October 2006, they reported the first successful clinical applications of the AWS in 10 consecutive patients requiring orotracheal intubation for neurosurgical procedures (3).

 

Asai and co-worker (1) evaluated the AWS for orotracheal inubation (performed by novice users of this device) in patients with apparently normal airway anatomy. Tracheal intubation was successful in 98 of 100 patients (in 96 patients on the first attempt and in 2 patients on the second attempt, respectively, despite some problems with fogging of the camera system); in one patient, laryngoscopy with the AWS was abondened because of loose teeths, and in a further one, tracheal intubation failed (after a maximum of two attempts) because the tracheal tube (TT) kept impacting on the arytenoids. Based on these results, the AWS may be a suitable alternative device for routine and difficult laryngoscopy and orotracheal intubation (because of ease handling and portability and provision of a wide visual view of laryngeal structures without requiring alignment of oral, pharyngeal, and laryngeal axes); however, further studies are required to substantiate these suggestions.

 

Enomoto and co-workers (2) recently published their experiences with the AWS in patients with normal airways but with manual cervical spine immobilization requiring orotracheal intubation for elective surgical procedures; AWS laryngeal views of the entire laryngeal were obtained in all 203 investigated patients, whereas Macintosh laryngeal views of only the epiglottis or the soft palate were encountered in 11 percent (22/203 patients). The study design provided only one tracheal intubation attempt with the randomized laryngoscope; AWS-assisted tracheal intubation was successful in 100 percent (99/99 patients) and failures with conventional tracheal intubation were observed in 89 percent 93/104 patients).

      

The AWS is composed of the main body with a miniaturized video screen (a movable liquid crystal display color monitor), the attachable camera unit (flexible, with a charge-coupled device sensor and a light-emitting diode), and the DLB. Light is supplied by two standard alkaline batteries incorporated in the main body of the AWS, activated by pressing the button on the right side of the AWS main body.

 

The DLB is currently available only in a single size for adults (with a maximum thickness of 18 mm) and supplied in a sterile packaging, ready for use. With the provision of the DLB, there is no need to wait for hygienic reprocessing of the device between uses, ideal for fast-paced tracheal intubation settings. The DLB incorporates a tube-guide channel on the right side to guide the TT and may be loaded with TTs up to 8.5 mm inner diameter; in addition, there is a further channel for passage of a suction catheter, when required.

 

For orotracheal intubation, the selected preformed and curved TT (tested for cuff leakage and lubricated with a water-soluble lubricant) is placed into the tube-guide channel of the DLB. The AWS system (with the attached camera unit and the DLB) is inserted in the midline into the oral cavity. The DLB should be placed beneath the epiglottis (Miller-laryngoscopy technique) to obtain a view of the laryngeal aperture (1, 2). When the green target symbol on the monitor is aligned with the laryngeal aperture, the TT may be advanced without difficulties and problems into a midtracheal position. Visualization of the tracheal intubation process is maintained throughout the procedure. The AWS body incorporates a video output, enabling visualization of the procedure on a NTSC-compatible external medical monitor.

 

 

References

1. Asai T, Enomoto Y, Shimuizu K, Shingu K, Okuda Y. The Pentax-AWS video-laryngoscope: the first experience in one hundred paients. Anesth Analg 106:257-259, 2008.

2. Enomoto Y, Asai T, Arai T, Kamishima K, Okuda Y. Pentax-AWS, a new videolaryngoscope, is more effective than the Macintosh laryngoscope for tracheal intubation in patients with restricted neck movements: A randomized comparative study. Br J Anaesth 100:544-548, 2008.

3. Koyama J, Aoyama T, Kusano Y, Seguchi T, Kawagishi K, Iwashita T, Okamoto K, Okudera H, Takasuna H, Hongo K. Description and first clinical application of AirWay Scope for tracheal intubation. J Neurosurg Anesthesiol 18:247-250, 2006.