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AFI is the gold standard of management for the difficult airway, and is found at the end of most algorithms which describe elective difficult intubation. Along with awake laryngscopy, this techniqye avoids the drama of an anaesthetic, with the patient remaining awake and breathing spontaneously up until their airway gets a cuffed tube into it. Its major disadvantages are the need for fiddly preparation, the reliance on patient cooperation and the risk of vomiting and aspiration with an insufficiently topicalised airway.
Question 13 from the first paper of 2016 and the identical Question 21 from the first paper of 2011 were the only questions to ever discuss AFI. It posed a situation where a hypoxic patient with ankylosing spondylitis requires a semi-elective awake fiberoptic intubation. This question separated the dual trainees in ICU and anaesthetics from those who don't routinely have their hands on an intubating bronchoscope. The college model answer to this question was actually quite good, and was reinterpreted into the Discussion section with minimal modification (only verbal pruning).
As far as publications go, one cannot go past the excellent LITFL page on this topic, which features hilarious videous (including one of Michael Bailin intubating himself). For most people this is enough. For those who instead wish to submerge into detail, Stephen Collins has written an excellent free article (Respiratory Care, 2014) which extends all the way to a discussion of bronchoscope engineering and the development of bronchoscopic technology. Practical details for airway topicalisation and bronchoscope steering can be found at frca.co.uk.
Why would you want to do this? Specifically, why do the various international societies recommend this procedure as the "gold standard" of difficult airway management? Well.
One may also use the same rationale to justify awake videolaryngoscopy. Rosenstock et al randomly allocated 93 adult difficult airway patients to be intubated either with a flexible bronchoscope or using the McGrath videolaryngoscope. For the AFI, first-attempt success rate was 79%, versus 71% for the McGrath. However, the McGrath group got their tubes in faster (at a median time of 62 seconds, instead of 80 seconds with the bronchoscope). Weirdly, one patient could not be intubated with the AFI and was successfulyl intubated with the McGrath (wait, which was the gold standard again?). Of course, all of these patients were reasonably healthy elective outpatients. The authors concluded that ultimately there is no difference between techniques, or at least if there is such a difference then their study was underpowered to find it (to detect an 8% difference in intubation success with 80% power they would have needed n=1000).
The following indications are composed of widely held beliefs and non-factual expert opinion. However, they make some sense. Here, they have been categorised according to which part of conventional intubation is made impossible by the patient factors.
Cannot move the C-spine
Cannot open mouth wide enough for the laryngoscope blade
Airway anatomy is very abnormal
Should not / cannot lie down to be intubated
Cricothyroidotomy is not an option
Risk and logistics do not favour other techniques
Walsh, Mary E., and G. D. Shorten. "Preparing to perform an awake fiberoptic intubation." The Yale journal of biology and medicine 71.6 (1998): 537.
Rosenstock, Charlotte V., et al. "Awake Fiberoptic or Awake Video Laryngoscopic Tracheal Intubation in Patients with Anticipated Difficult Airway ManagementA Randomized Clinical Trial." The Journal of the American Society of Anesthesiologists 116.6 (2012): 1210-1216.
Leslie, David, and Mark Stacey. "Awake intubation." Continuing Education in Anaesthesia, Critical Care & Pain (2014): mku015.
Peterson, Gene N., et al. "Management of the Difficult AirwayA Closed Claims Analysis." The Journal of the American Society of Anesthesiologists 103.1 (2005): 33-39.
Ramkumar, Venkateswaran. "Preparation of the patient and the airway for awake intubation." Indian journal of anaesthesia 55.5 (2011): 442.
Collins, Stephen R., and Randal S. Blank. "Fiberoptic intubation: an overview and update." Respiratory care 59.6 (2014): 865-880.