Modified Guedel's airway for facilitation of fiberoptic laryngoscopy.

Sir,

Fiberoptic laryngoscopy (FOL) is an important armamentarium for managing difficult airway. FOL is used for intubating the trachea in awake patients or in patients under general anesthesia. Literature proves the usefulness of various oral airways in facilitation of endotracheal intubation (ETI) using FOL.[1-3] Oral airways aid in mask ventilation and directing the scope towards the glottis during FOL. During FOL in awake patients, these airways serve as the bite blocks while in FOL after induction of anesthesia these airways maintain the contour of the oropharynx. Several types of airway are available for this purpose namely William's airway, Berman's airway, Ovassapian's airway. Various modifications of the oral airways have been suggested from time to time.[4] We have modified the Guedel's airway to serve as FOL assist airway. In three simple steps, we can convert a conventional Guedel's airway to FOL assist airway.

Step 1: An appropriate size Guedel's airway is taken and an 8mm strip of the plastic is cut from the convex surface [Figure 1].

Figure 1

The posterior aspect of the modified Guedel's airway along with the bite block.

Step 2: An 8mm strip of plastic is cut from the color coded bite block if a 5mm FOL is to be used [Figure 1].

Step 3: The bite block is inserted into the airway so that the cut surface of the airway and bite blocks is opposite to each other [Figure 2].

Figure 2

The method of insertion of the bite block into the Guedel's airway. The two cut surface are placed opposite to each other. This maneuver helps retain the scope in the airway

This modified Guedel's airway is inserted just like a conventional Guedel's airway. The fiber-optic scope is inserted through the channel in the bite block and the scope is forwarded along the length of airway to visualize the glottis. Once the trachea has been entered, the airway has to be removed and the endotracheal tube rail-roaded in. While removing the airway over the scope the bite block has to be removed first followed by the airway.

We have used this airway in fifty patients, achieving almost hundred percent success rates. This modification of the airway is easily designed, cheap and disposable and due to the shape of the Guedel's airway the distal end directs the scope to the glottis. Users have to remember that choosing an inappropriate sized airway may make their task difficult instead of simplifying it. One limitation of this airway is that it cannot be inserted in patients with restricted mouth opening.