Awake nasotracheal intubation using videolaryngoscopy or fibreoptic bronchoscopy

The recent article by Kramer et al. [1] showed that in patients with an anticipated difficult airway, awake nasal intubation using a C-MAC D-BLADE videolaryngoscope yielded the same success rate as using a fibreoptic bronchoscope, but in a shorter intubation time. Furthermore, the satisfaction of patients and anaesthetists was similar in both groups. Accordingly, they conclude that a videolaryngoscope represents an acceptable alternative to fibreoptic bronchoscopy for awake intubation. However, we would invite the authors to comment on some questions we have about their methodology. Firstly, was there any assessment made of the efficacy of topical anaesthesia between the two devices? Fibreoptic bronchoscopy is normally considered the gold standard for difficult airway managament, in part because of the ability to provide ‘spray as you go’ topical anaesthesia [2, 3]. To date, no-one has similarly studied topical anaesthesia during videolaryngoscopy, and because insertion of the videolaryngoscope can cause pressure on the tongue and the laryngeal structures, we would argue that videolaryngoscopy may cause a greater degree of patient discomfort than fibreoptic bronchoscopy. Secondly, was a true comparison made between intubation times? The authors define intubation time as that from insertion of the videolaryngoscope into the mouth or insertion of the fibrescope into the nasal tube, until the tube’s cuff was inflated [1], but we think that, with a nasal tube already placed in the nasal passage, nasal intubation with a videolaryngoscope is different from that using fibreoptic bronchoscopy. When the larynx is seen with videolaryngoscopy, advancement of the nasal tube into the trachea is a straightforward process. Using fibreoptic bronchoscopy, however, several problems can occur if the tube is placed into the nasal passage first. Firstly, nasal bleeding can obscure the view of the trachea. Secondly, insertion of a 5.2mm fibrescope through the tube placed in the nasal passage is often difficult, especially when a 6.0-mm tube or a preformed nasal tube is used. Thirdly, the direction established by the nasal tube prevents manipulation of the fibrescope into the glottis. Do the authors accept that the above factors could have prolonged intubation time in the fibreoptic bronchoscopy group, and that different results might have been obtained if the nasal tube had first been mounted over the fibrescope before onward passage through the nose? Finally, the Ramsay sedation score was originally designed as a six-point scoring system, with a score range of 1-6 [4]. In this study, a seven-point scoring system with a score range of 0-6 was used. Is this a modified version of the original scoring system? If so, could the authors provide the reference and scoring standards of this modified version to avoid confusion? For example, according to the results provided in their Table 1, awake intubation was performed in all patients with a Ramsay sedation score ≤ 3. This sedation depth is insufficient for awake intubation. To ensure the comfort of awake patients and subsequent successful instrumentation in our practice, a Ramsay sedation