Conduit For Tracheal Intubation Research Articles

A New Algorithm for Pediatric Airway Management Using the Intubating Laryngeal Airway

Objective: 1) Evaluate the use of the intubating laryngeal airway (ILA) in providing safe endotracheal intubations in pediatric patients with difficult airways. 2) Present a management algorithm using direct laryngoscopy, rigid bronchoscopy, and the ILA for evaluating and securing the airway in pediatric patients with difficult airways. Method: The medical records of patients in whom the ILA was used to secure the airway from January 2009 to January 2011 were reviewed. We documented the circumstances necessitating airway management, success of the ILA, airway evaluation findings, and medical conditions contributing to the difficult airway. Results: A total of 50 patients had an ILA placed for airway management. Nine out of 50 (18%) were performed emergently. The median age was 59.8 months (range, 0.3-244.1 months), and the median weight was 19.0 kg (range, 2.6-86 kg). Four cases (8%) were unanticipated difficult airways, and 46 out of 50 (92%) were anticipated difficult airways. Comorbid conditions included craniofacial syndromes (n = 36), cervical spine instability or immobility (n = 9), and airway hemorrhage (n = 3). A total of 48 out of 50 (96%) patients were intubated on the first attempt through the ILA. In 2 patients intubation required a second attempt. The overall success rate using the ILA to secure the airway was 100%. Conclusion: ILA is safe and effective in pediatric patients with a difficult airway as a conduit for tracheal intubation. Our proposed algorithm for difficult pediatric airway provides a safe means for anesthesiologists and otolaryngolgists to evaluate and secure the airway in these patients.

Comparison of blind tracheal intubation through the intubating laryngeal mask airway (LMA FastrachTM) and the Air‐QTM

This study assessed two disposable devices, the LMA Fastrach™ and the newly developed supraglottic airway device, the Air-Q™, as a conduit for tracheal intubation in 154 healthy adults undergoing elective surgery. Using a non-inferiority approach, the primary outcome measure was successful tracheal intubation within two blind insertion attempts. Successful blind intubation after two attempts was achieved in 75/76 (99%) of the patients in the LMA Fastrach group vs 60/78 (77%) in the Air-Q group (95% CI for the difference 12-32%, p<0.0001). Fibreoptic intubation was used to assist the third attempt. The rate of successful intubation after three attempts was 100% in the LMA Fastrach group and 95% in Air-Q group. The single-use LMA Fastrach appears superior compared with the Air-Q, as a conduit to facilitate blind tracheal intubation.

Retrospective audit of the air‐Q intubating laryngeal airway as a conduit for tracheal intubation in pediatric patients with a difficult airway

To assess the efficacy of the ILA as a conduit for tracheal intubation in pediatric patients with a difficult airway. The primary goals of this retrospective audit were to assess the clinical performance of the ILA in pediatric patients with a difficult airway, expand on our initial favorable experience with this device, and collect pilot data for future prospective and comparison studies. The charts of patients with a difficult airway in whom the ILA was used during a period of 1 year in a freestanding pediatric institution were reviewed following a practice change in the authors' institution favoring the ILA over the laryngeal mask airway as a conduit for tracheal intubation. Thirty-four pediatric patients had an ILA placed during the course of their airway management. Eight of the 34 patients in this cohort required emergent airway management. The median age was 47.1 (0.3-202.2) months and the median weight was 16.3 (3.9-86.0) kilograms. Three of the cases were unanticipated difficult airways and the remaining were anticipated difficult airways as a result of craniofacial syndromes (n = 21), cervical spine instability or immobility (n = 7), or airway hemorrhage (n = 3). Thirty-three of the 34 patients (97%) were intubated on the first attempt through the ILA, with the aid of a fiberoptic bronchoscope (n = 25), a Shikani Optical Stylet (n = 7), or blindly (n = 2). In one patient, blind tracheal intubation required a second attempt for successful intubation, making the overall success rate 100%. Oxygen desaturation was noted in 6 of the 34 cases. In a series of pediatric patients with difficult airways, the ILA was successfully used as a conduit for tracheal intubation in all patients. Visualization techniques may offer a greater degree of success in intubations through the ILA due to the potential for epiglottic down-folding in children.

An airway exchange catheter facilitates removal of the intubating laryngeal airway after tracheal intubation in children

To the Editor, When encountering patients with difficult airways in pediatric anesthesia, clinicians have the option of using a supraglottic airway device as a conduit for tracheal intubation. The Laryngeal Mask Airway (LMA) Classic (LMA North America; San Diego, CA, USA) is the conduit used most commonly for tracheal intubation in the pediatric population. However, numerous challenges arise when the LMA is used to facilitate intubation with an endotracheal tube (ETT), especially during removal of the LMA following successful intubation. In particular, the airway tube of the LMA can be as long as the ETT, making it difficult to maintain control of the ETT while removing the LMA. Several techniques that decrease the likelihood of accidental extubation of the ETT during removal of the LMA have been devised and reported in the literature. These techniques include the use of a long ETT, a double ETT assembly, shortening or splitting the shaft of the LMA, or leaving the LMA in place for the duration of surgery. These techniques are all effective yet imperfect solutions to a procedure commonly encountered in a patient with a difficult airway. The air-Q intubating laryngeal airway (ILA) (Cookgas LLC; St. Louis, MO, USA) is a newer supraglottic airway device that holds several advantages over the LMA when used to facilitate tracheal intubation in the pediatric population. Specifically, the airway tube of the ILA is shorter and wider than the LMA, which allows for greater control of the ETT and unhindered passage of the pilot balloon during removal of the ILA. At our institution, we have intubated the tracheas of hundreds of patients successfully by using the ILA as a conduit for tracheal intubation. It has been noted that the shorter airway tube length greatly facilitates distal control of the ETT and subsequent removal of the ILA after intubation. Unlike the LMA, the ILA has a custom removal stylet that can be used to stabilize the ETT during removal of the ILA device. However, if the manufacturer’s removal stylet is not available or if the clinician is not comfortable with its use, we propose the use of an airway exchange catheter (AEC) (Cook Medical, Bloomington, IN, USA) to facilitate removal of the ILA (Figure). Use of an AEC during removal of the ILA offers advantages to the clinician who otherwise might be hesitant to remove the ILA after tracheal intubation. First, placement of the AEC maintains the ability to supply supplemental oxygen into the trachea and diminishes the possibility of oxygen desaturation. Second, the AEC provides a means for guided reintubation if the ETT is dislodged inadvertently during removal of the ILA device. Generally, the smaller-sized ILAs (1.0 and 1.5) are short enough to facilitate gaining both proximal and distal control of the ETT during removal of the ILA. If an AEC is used, the clinician could cede control of the ETT once its proximal end is flush with the ILA and still retain proximal control of the AEC to ensure it remains in the trachea. The clinician can then remove the ILA until distal control of the ETT is possible, even if outside the patient’s mouth, and then confirm tracheal depth and reintubate over the AEC if necessary. Another potential technique that has been described for tracheal intubation through the LMA is to leave the fibreoptic bronchoscope within the trachea while removing the LMA, then to advance the ETT down the bronchoscope into the trachea. This method is beneficial, as no additional N. Jagannathan, MD (&) R. J. Kozlowski, BS Children’s Memorial Hospital, Northwestern University’s Feinberg School of Medicine, Chicago, IL, USA e-mail: simjag2000@yahoo.com

Caution is essential when using a tracheal tube as a stabilizing rod to remove the Intubating Laryngeal Airway (ILA™) after tracheal intubation in children

To the Editor, Use of a supraglottic airway device as a conduit for tracheal intubation has changed the practice of pediatric anesthesia, especially in the management of patients with difficult airways. For many years, the Laryngeal Mask Airway (LMA) Classic (LMA North America, San Diego, CA, USA) was the device most commonly used for this purpose in pediatric anesthesia. However, there are some limitations when the LMA is used to facilitate fibreoptic intubation with a cuffed endotracheal tube (ETT), particularly during subsequent removal of the LMA. The Intubating Laryngeal Airway (ILA) (Cookgas LLC, St. Louis, MO, USA) is a new supraglottic airway device that is comparable to the LMA in terms of its ease of insertion and functionality, but with a conduit sufficient in size to accommodate a larger cuffed ETT. There are no intubating LMAs currently available for patients weighing \30 kg, and the ILA, which is available in pediatric sizes, can be used to facilitate tracheal intubation in these patients. A Stabilizer Rod is used to facilitate removal of the LMA after successful tracheal intubation. Like the LMA, the ILA has a Removal Stylet available to steady the ETT during removal of the ILA device. The ILA lumen is of sufficient size to accommodate the Stylet and the pilot balloon of the ETT during withdrawal of the ILA (Figure 1A-C). In clinical practice, however, an uncuffed ETT is often used in lieu of the manufacturer’s removal stylet when removing the LMA or ILA after using either as a conduit for tracheal intubation in children (Figure 1D-F). The ILA lumen cannot accommodate both the pilot balloon and the ETT during ILA withdrawal (Figure 1F), and entrapment of the pilot balloon within the airway tube may lead to cuff line rupture if the ILA is withdrawn further in that situation. The disadvantages of using two tracheal tubes include the potential for cuff line rupture or inadvertent ETT dislodgement upon removal of the ILA. To avoid either situation, control of the distal cuffed ETT must be maintained while the proximal ETT is first removed from the ILA (Figure 1E). After that, the cuff line and the pilot balloon can pass through the ILA airway tube unhindered. This is of particular importance in the management of the difficult airway, where the initial securing of the airway may have been difficult and where re-intubation may be accompanied by untoward problems. It is convenient to use a second ETT as a stabilizing rod for removal of the ILA after successful tracheal intubation, because an ETT is readily available in the operating room and is used commonly when removing the LMA-Classic after tracheal intubation in pediatric patients. As the ILA and tracheal intubation with cuffed ETTs become more common in pediatric anesthesia, awareness of the limitations of using an ETT as a stabilizing rod to assist in removal of the ILA is clinically important. In our clinical experience of more than 100 ILA-guided tracheal intubations, we have used a tracheal tube primarily as a stabilizing rod when removing the ILA. However, we have encountered difficulty when removing the ILA with the use N. Jagannathan, MD (&) M. F. Kho, MS Children’s Memorial Hospital, Northwestern University’s Feinberg School of Medicine, Chicago, IL, USA e-mail: simjag2000@yahoo.com

A comparison of the I-gel supraglottic airway as a conduit for tracheal intubation with the intubating laryngeal mask airway: A manikin study

Background Insertion of a supraglottic airway and tracheal intubation through it may be indicated in resuscitation scenarios where conventional laryngoscopy fails. Various supraglottic devices have been used as conduits for tracheal intubation, including the intubating laryngeal mask airway (ILMA), the Ctrach™ laryngeal mask and the I-gel supraglottic airway. Methods A prospective study with 25 participants evaluated the success rate of blind intubation (using a gum-elastic bougie, an Aintree intubating catheter (AIC) and designated tracheal tube) and fibrescope-guided tracheal intubation (through the intubating laryngeal mask airway and the I-gel supraglottic airway) on three different airway manikins. Results Twenty-five anaesthetists performed three intubations with each method on each of three manikins. The success rate of the fibrescope-guided technique was significantly higher than blind attempts ( P < 0.0001) with both devices. For fibreoptic techniques, there was no difference found between the ILMA and I-gel ( P > 0.05). All blind techniques were significantly more successful in the ILMA group compared to the I-gel ( P < 0.0001 for bougie, Aintree catheter and tracheal tube, respectively). Conclusions The results of this study show that, in manikins, fibreoptic intubation through both ILMA and I-gel is a highly successful technique. Blind intubation through the I-gel showed a low success rate and should not be attempted.

Evaluation of the Cobra perilaryngeal airway (CPLA) as an airway conduit*

The effectiveness of the Cobra perilaryngeal airway as a routine airway device and as a conduit for tracheal intubation has not been prospectively studied to date. This study aimed to evaluate the Cobra perilaryngeal airway for its potential role in an emergency airway rescue, by analysing its use as a bridge to blind or fibre-optic-guided intubation. In 49 patients, the procedure was carried out as follows: fibre-optic view through the Cobra perilaryngeal airway was assessed after the insertion of the Cobra perilaryngeal airway, then blind intubation through the Cobra perilaryngeal airway was attempted. After evaluating the success of blind intubation, fibre-optic-guided intubation was performed through the Cobra perilaryngeal airway. The endotracheal tube was removed after evaluating the success of fibre-optic-guided intubation, and then conventional laryngoscopy was carried out to evaluate the Cormack & Lehane grade and airway trauma. In all, 95.9% (47/49) of patients had adequate ventilation using the Cobra perilaryngeal airway; the success rates for the blind and fibre-optic-guided intubation were 36.2% and 83.0%, respectively. The patients were divided into two groups according to the fibre-optic view. Group 1 included patients with an obstructed view by an anterior grill of the Cobra perilaryngeal airway head, and a view of the anterior epiglottis (downfolded epiglottis) with or without a visible larynx (16/47, 34.0%). Group 2 included the remaining patients (31/47, 66.0%). The success rates of the blind and fibre-optic intubations were different between the two groups (blind intubation: 12.5% vs. 48.4%, fibre-optic intubation: 62.5% vs. 93.6%, P 0.05). 42.6% of patients had blood staining after removing the device and complications such as trauma and oedema were confirmed under direct laryngoscopy. This study suggests that the Cobra perilaryngeal airway could be a useful airway device as a vehicle for fibre-optic-guided intubation; however, it needs caution against airway trauma.

Prediction of a Low Success Rate of Astronauts in Space in Performing Endotracheal Intubation

We certainly concur with Rabitsch et al. 1that tracheal intubation using direct laryngoscopy by astronauts in space is likely to have a high failure rate. Roan first presented this concept and the use of the Laryngeal Mask Airway ™ (LMA ™; LMA North America, Inc., San Diego, CA) as a backup emergency airway device to the National Aeronautics and Space Administration in October 1999*and later at the Aerospace Medical Association Conference in 2001.†In fact, since 2003, the LMA-Fastrach ™ has been used on the space shuttle as a backup airway device.Several reasons exist that predict a low success rate of astronauts in space in performing tracheal intubation. Although some crew medical officers (CMOs) are physicians, often the CMO may have no medical background. The training CMOs receive on the proper use of the bag valve mask resuscitator, oral airway, tracheal intubation, and surgical cricothyroidotomy is limited, and even physician CMOs are likely to have had several years pass since the last clinical exposure to this scenario. Studies have found that experienced emergency medical technicians (basic), with two to three times the amount of training provided to CMOs, have only approximately a 50% success rate of tracheal intubation in human subjects.2,3A compounding factor further increasing the likelihood of failed intubation is the condition of microgravity while in orbit.The ideal airway for astronaut CMOs would possess a very short learning curve as well as require little experience to master and maintain proficiency. Rabitsch et al. 1chose the Esophageal Tracheal Combitube® (Kendall Sheridan Healthcare Products Company, Argyle, NY) as a backup airway device for failed tracheal intubation. Although requiring less training and skill than direct laryngoscopy, the use of the Combitube® as a rescue airway for failed intubation has shown an overall complication rate of up to 40%, including failure to place, aspiration, pneumothorax, esophageal perforation and laceration, among others.4,5Also, the presence of two lumens may prove confusing to the relative novice under the many stressors of an emergency; clearly, the wrong lumen choice would have disastrous consequences.Although an oral airway and manual resuscitator with facemask is another option, it is well known that ventilation with this device can be challenging for even the most highly trained personnel. On the other hand, 100% of 32 nurses without previous experience in the use of the LMA ™ were able to successfully ventilate live patients 3 months after manikin-only training.6The complication rate of the LMA ™ is quite low, and when used as a primary airway rescue device for failed intubation, it has provided rescue ventilation without complication in 94% of failed intubation cases.7Although the standard LMA ™ has a high success rate as a conduit for tracheal intubation, the LMA-Fastrach ™ is specifically designed to facilitate this. Therefore, it was chosen for the shuttle orbiters and the International Space Station because it most closely meets the criteria delineated above of a short learning curve with a high success rate and easily maintained insertion proficiency.‡University of Alabama at Birmingham, Birmingham, Alabama. gboyd@uab.edu

Laryngeal mask airway and the ASA difficult airway algorithm.

Laryngeal mask airway and the ASA difficult airway algorithm.