The intubating laryngeal mask airway (ILMA) (Fastrach, LMA of North America, San Diego, CA, USA) is a derivation of the laryngeal mask airway (LMA) that facilitates both ventilation and blind endotracheal intubation. The device has several features that distinguish it from the standard laryngeal mask device. The intubating laryngeal mask consists of a soft mask that fits over the larynx, attached to a rigid stainless steel tube. The lumen of the tube has a larger internal diameter than the standard LMA and is attached to a handle to facilitate insertion. This tube admits a flexible, reinforced endotracheal tube (ETT) specifically manufactured for this laryngeal mask. The device comes in three sizes for adults (3, 4, and 5), all of which can admit a range of ETT sizes, up to size 8.0. Other manufacturers have begun to offer similar devices, such as the Air-Q Reusable Laryngeal Mask (Mercury Medical, Clearwater, FL, USA) and Ambu Aura-I (Ambu Inc., Glen Burnie, MD, USA). Both provide a means of intubation through the device but do not have the steel barrel, handle, or epiglottic elevating bar (EEB), which are features of the ILMA.

The ILMA device has proven useful for managing the difficult airway in various settings. The popularity of the LMA in Europe and around the world has led to ready acceptance of the ILMA. The ILMA is relatively easy to use. Those with limited airway management experience may be more successful with the ILMA than with conventional methods. Timmerman et al¹ showed that medical students ventilate and intubate quicker and more effectively via ILMA than by conventional bag-mask ventilation and laryngoscopy. Thirty medical students, each intubated three patients using each method. Ventilation was significantly more successful with the ILMA (97.8% vs 85.6%). Intubation was also more successful using the ILMA (92.2% vs 40.0%). In Australia, Agro² described its use in 110 patients slated for general anesthesia, with 95% success. However, the authors encountered resistance to ETT insertion in 60% of patients, which required some form of adjustment. The average time required for the authors to intubate patients was 79 seconds. In a multicenter study from the United Kingdom, Baskett³ assessed the efficacy of the ILMA in intubation of 500 patients undergoing general anesthesia, with 95% success in ventilation through the mask portion of the device. The authors had 80% intubation success on the first attempt, with 4% of patients requiring three attempts, and an overall failure rate of 4%. Brain⁴ used the ILMA in 150 patients undergoing general anesthesia, with successful ventilation of all patients. In half of the patients, resistance to ETT insertion through the device occurred, requiring one of several described “adjusting maneuvers” before intubation was accomplished. The study included 13 patients with potential or known difficult airway anatomy, all of whom were intubated successfully. Four different adjusting maneuvers were suggested (Table 27-1),
depending upon the depth at which resistance to the ETT advancement was encountered.³

In 38 patients with known difficult airway anatomy (based on patient history or physical examination), Joo⁵ assessed the utility of the ILMA compared with awake intubation with the fiberoptic bronchoscope (FOB). All awake FOB attempts were successful, but only half of the patients could be intubated blindly with the ILMA. The other half required use of a bronchoscope, and 10% required involvement of a second operator to place the ETT. In another evaluation of this device in patients with known or suspected difficult airways, Ferson et al⁶ evaluated the utility of the ILMA in 257 patients: 78% after induction of anesthesia, and 20% awake, with topical anesthesia (in 2% of cases, patients were unconscious and no anesthetic was provided). The authors were able to successfully ventilate all of these patients, and ETT insertion was accomplished blindly in 96.5% of the 200 in whom it was attempted (the remainder were intubated with FOB, using the ILMA as an introducer device), 75% on the first attempt.

In a study of the efficacy of the ILMA in obese patients, Combes et al⁷ found that the device required less adjusting maneuvers and fewer attempts at blind placement than in lean subjects, with similar overall intubation success rates (96% vs 94%, respectively). Among anesthetized patients where in-line cervical immobilization was used to simulate cervical spine trauma, Komatsu et al⁸ found that the ILMA was simpler and quicker to insert than another supraglottic ventilation device, the laryngeal tube, and allowed ventilation with larger tidal volumes. Other case series also indicate that the ILMA can be used safely in patients with cervical spine injuries or disorder.⁹,¹⁰ In a retrospective review by Ferson et al,⁶ 70 patients with known unstable c-spines and immobilized with rigid collars were successfully intubated blindly using an ILMA with a 92.6% success rate on the first attempt. In five cases (7.4%), two attempts were needed. FOB assistance was used electively in two of the five cases for the second attempt. The use of the ILMA was not implicated in any new neurologic deficits in these patients.