Overview
The PENTAX-AWS (AWS) is a rigid indirect video laryngoscope developed in Japan. The AWS consists of 2.4-inch full-color built-in monitor screen, a charge-coupled device (CCD) camera, and a PBLADE, a disposable blade designed by referring to computed tomography images of the pharynx and larynx of Japanese adults. Unlike conventional direct laryngoscopes, the PBLADE is formed in an “L” shape so as to fit the oropharyngeal anatomy, thus enabling the operator to obtain an optimal view for tracheal intubation without requiring alignment of the oral, pharyngeal, and tracheal axes. In addition, no specific neck position such as the sniffing position or powerful force is required during a laryngoscopy procedure with the device. These characteristics enable safe and secure tracheal intubation regardless of operator experience, even in some difficult airway cases, such as cervical spine immobilization and difficult laryngoscopy, as well as others. As a result, a number of clinical studies have indicated the efficacy of the AWS.
On the other hand, initial evaluations of the AWS are not always good among well-experienced operators who have been using a Macintosh laryngoscope, since the procedures of tracheal intubation differ between the two devices. In particular, manipulation of a PBLADE in the same manner as a Macintosh laryngoscope blade may make it difficult for operators to perform tracheal intubation using the AWS.
The AWS is not the ultimate device for tracheal intubation. Limited mouth opening and copious secretion or blood in the oral cavity are disadvantageous. Moreover, there is a possibility of difficulty with inserting the PBLADE in patients with anatomical abnormalities of the pharynx or larynx.
Here, we focus on the basic anatomical knowledge and skills needed for proper use of the AWS. By understanding its features and learning the correct procedures, the operator can make the best use of the merits of this device. Our hope is that our instructions will be helpful for obtaining accurate knowledge and proper use of the AWS, as well as understanding its limitations.