The standard oral or oropharyngeal airways are rigid plastic tubes which are shaped according to the outline of the hard and soft palate, against which they sit inside the mouth if placed correctly. They have a flange that should rest against the patient's lips and prevent the device from being inserted too deeply into the mouth. Most manufacturers adhere to a standardized color-coding system of sizes. The typical adult sizes are green, yellow, and red by increasing size.
Other types of oropharyngel airway are available, which, in addtition to creating and maintaining airway patency, are specifically designed to facilitate oral fiberoptic intubation, which means they can accomodate an ET tube. Here we will briefly desctibe the Berman and Ovassapian airways.
Berman and Ovassapian airways
The Berman and Ovassapian airways; top-down view
The Berman and Ovassapian airways; side view
The Berman and Ovassapian airways; view from the front showing the channels for the fiberoptic bronchoscope and ET tube
The Berman airway is a very helpful device for oral fiberoptic intubation. It has a channel accomodating the bronchoscope and/ or ET tube which open at one side. After successful intubation the Berman airway can be 'broken' open and removed from the ET tube.
The Ovassapian airway is also used for oral fiberoptic intubation. It features some plastic ridges in its design which guide the ET tube in the midline. A disadvantage of this airway in comparison with the Berman airway is the fact that there is no 'channel' for the distal half of the airway, where it is pretty much just a flat plastic blade. This means that the Ovassapian airway does not create a channel for the fiberoptic bronchoscope to pass through the oropharynx. The tongue can still occlude the airway against the soft palate which causes poor visiblity during advancement of the fiberoptic scope..
Side view of the Ovassapian (top) and Berman (bottom) airways; the lack of a guiding channel in the Ovassapian airway is marked in red
PERSONAL OPINION: For oral fiberoptic intubations I prefer the Berman over the Ovassapian airway. With the Ovassapian it is difficult to avoid having soft tissue, i.e. tongue and soft palate, collapse around the fiberoptic scope and ruining the view for a bit as you advance the scope. Unfortunately, at the time of writing, the Berman airway is no longer being marketed in the U.S.
These devices are used to help with creating and mainaining a patent upper airway, often in conjunction with the basic airway maneuvers.
Chosing the correct size and insertion of oropharyngeal airways is descibed in the 'basic airway maneuvers' article.
The Berman and Ovassapian airways are really only useful for oral fiberoptic intubation.
How to use the Berman and Ovassapian airways is described in the article on oral fiberoptic intubation.