Just as the laryngeal mask airway (LMA) does, the intubating laryngeal mask airway (ILMA) provides an excellent conduit from the mouth to the laryngeal orifice, sitting astride the glottis when properly placed. Some differences between these two ventilation adjuncts exist: the steel barrel of the ILMA makes a right angle as it enters the pharynx, as opposed to the gradual curve of the standard LMA lumen; the distal end of the ILMA lumen is guarded by an epiglottic elevating bar, rather than a grid; and the barrel of the ILMA is larger than that of the standard LMA, as it was designed to facilitate intubation of the trachea. The size 3, 4, and 5 ILMA all permit intubation with an 8.0 internal diameter endotracheal tube (ETT). The provider may insert an ILMA and immediately choose a fiberoptic bronchoscope (FOB) for guided intubation or may choose to attempt blind intubation through the device and call the FOB into play only if this fails.

The utility of intubation through the ILMA using FOB guidance has been established through several case series and comparative trials. Joo¹ randomized 38 patients with known difficult airways to either awake intubation with FOB or to intubation after anesthesia with ILMA. In half of the latter group, the patients could not be intubated blindly with ILMA. However, in all of these, FOB was used successfully to intubate through the device. Ferson² investigated the utility of ILMA in patients with known or suspected difficult airways (cervical immobilization; failed intubation during direct laryngoscopy; or distorted airway anatomy due to tumor, surgery, or radiation therapy). In 54 of 254 patients, FOB was chosen to guide intubation through the ILMA device from the outset, whereas in the other 200, blind intubation was initiated (up to 5 attempts). The FOB was successful in 100% of the designated cases, on the first attempt. In 7 cases selected for blind intubation, the ETT could not be placed in the trachea, and FOB was used for rescue, which was also successful on the first attempt in all cases.