Intubation through supraglottic airway devices has become a standard procedure in failed intubation. Within the supraglottic airway device family, the Intubating Laryngeal Mask Airway (ILMA) Fastrach has a unique position, featuring unsurpassed high blind intubation success rates of over 80%.1–4 Recently, other supraglottic airway devices are being introduced to the market and also offer the possibility of serving as guidance for tracheal intubation. Owing to their lower costs, these alternatives to the ILMA Fastrach have become a focus of interest for anaesthesia providers.2–5 It has been shown that fibreoptic-guided intubation through various supraglottic airway devices is a highly successful technique in both adults6 and children.7 However, according to current data, the results for blind intubation through these supraglottic airway devices are substantially poorer.
We have read the letter by Dr Gaszynski with great interest.8 In an observational study, he evaluated the possibility of blind intubation through the Air-Q supraglottic airway device in morbidly obese adults and found a success rate of only 24%.8 Of note, Dr Gaszynski studied morbidly obese patients, not patients with confirmed or unexpected difficult intubation.8 In a previous study, we showed that blind intubation through the Air-Q in children had a success rate of only 15%.5 Interestingly, Dr Gaszynski has confirmed our results in an entirely different patient population. Both studies revealed success rates of blind intubation through the Air-Q that are unacceptably low for a supraglottic airway device that may be used as a rescue device.
We also evaluated blind intubation through the i-gel supraglottic airway device in adults with predictors for difficult intubation and found a success rate of only 15%.2 In children, the Ambu Aura-i supraglottic airway device showed a blind intubation success rate of only 4%,5 but more extensive data on blind intubation through supraglottic airway devices of the Ambu family are lacking. Because airway management in children,5 patients with a predicted difficult airway2 and the obese8 can be particularly challenging, it is not surprising that studies in patients with a nondifficult airway showed first-attempt blind intubation success rates through the Air-Q that were higher (57 to 69%).3,4 Nevertheless, for devices that are meant to be backup devices in a failed airway management algorithm, even these success rates remain unacceptably low.
In conclusion, blind intubation through new supraglottic airway devices such as the Air-Q, the i-gel and the paediatric Ambu Aura-i cannot be recommended. So far, no study has been able to identify a supraglottic airway device that reaches blind intubation success rates similar to those of the ILMA Fastrach. Many supraglottic airway devices can be used for intubation, but only with fibreoptic guidance. At present, the ILMA Fastrach remains the gold standard for blind tracheal intubation through supraglottic airway devices.
Acknowledgements related to this article
Assistance with the letter: the authors would like to thank Tobias Hornshaw, Department of Anaesthesiology and Pain Therapy, University Hospital Bern, Switzerland, for English editing.
Financial support and sponsorship: this work was funded by an institutional research grant of the Department of Anaesthesiology and Pain Medicine – Inselspital, Bern University Hospital, Switzerland.
Conflicts of interest: none.
1. Brain AI, Verghese C, Addy EV, et al. The intubating laryngeal mask. II: a preliminary clinical report of a new means of intubating the trachea. Br J Anaesth
2. Theiler L, Kleine-Brueggeney M, Urwyler N, et al. Randomized clinical trial of the i-gel and Magill tracheal tube or single-use ILMA and ILMA tracheal tube for blind intubation in anaesthetized patients with a predicted difficult airway. Br J Anaesth
3. Karim YM, Swanson DE. Comparison of blind tracheal intubation through the intubating laryngeal mask airway (LMA Fastrach) and the Air-Q. Anaesthesia
4. Erlacher W, Tiefenbrunner H, Kastenbauer T, et al. CobraPLUS and Cookgas air-Q versus Fastrach for blind endotracheal intubation: a randomised controlled trial. Eur J Anaesthesiol
5. Kleine-Brueggeney M, Nicolet A, Nabecker S, et al. Blind intubation of anaesthetised children with supraglottic airway devices AmbuAura-i and Air-Q cannot be recommended: a randomised controlled trial. Eur J Anaesthesiol
6. Kleine-Brueggeney M, Theiler L, Urwyler N, et al. Randomized trial comparing the i-gel and Magill tracheal tube with the single-use ILMA and ILMA tracheal tube for fibreoptic-guided intubation in anaesthetized patients with a predicted difficult airway. Br J Anaesth
7. Jagannathan N, Sohn LE, Sawardekar A, et al. A randomized trial comparing the Ambu (R) Aura-i with the air-Q intubating laryngeal airway as conduits for tracheal intubation in children. Paediatr Anaesth
8. Gaszynski T. Blind intubation through Air-Q SP laryngeal mask in morbidly obese patients. Eur J Anaesthesiol