Comparing performance of flexible bronchoscopy with videolaryngoscopy for awake tracheal intubation: a reply

We thank Xue et al. [1] for their interest in our article [2] and we are happy to address their queries. First, both groups had the same local anaesthesia and sedation regimen made up of superior laryngeal nerve block, tracheal block and remifentanil sedation. The only difference was that the entry point for anaesthesia was a piece of gauze impregnated with 5% lidocaine in the fibreoptic group and 3–4 sprays of 5% lidocaine in patients allocated to the Airtraq® (Prodol Meditec S.A., Vizcaya, Spain) group. We agree that nerve blocks are invasive compared with ‘spray as you go’ techniques. However, laryngeal block provides predictable, long-lasting and stable anaesthesia without entering the larynx itself. This minimises the risk of worsening or producing respiratory distress [3]. Second, this strategy permitted novices to undertake their first attempt with a well-anaesthetised larynx. Third, with appropriate explanation and a good sedation regimen, it was comfortable for the patients, with good satisfaction scores. The novices in this study were anaesthesia residents who spent 6 months in our department. They claimed to be comfortable with the Airtraq device in patients under general anaesthesia and had performed several bronchoscopies but none of them could achieve awake tracheal intubation, even under the supervision of an expert. With a comparable background in awake tracheal intubation and equal distribution among groups (69% vs. 72%, p = 0.800), we felt that the bias related to the trainees' background was of little importance to the result. However, although the success rate of these novices was low compared with experts, it was still appreciable for a first awake tracheal intubation in real-life situations. We have found no comparable data published elsewhere. The Airtraq device can only be used orally, while bronchoscopy can be performed either orally or nasally. We decided to use the nasal route with bronchoscopy to approximate real life. In our centre, we use bronchoscopy via the nasal route unless the surgery requires the nose to be free and we excluded these patients from this study. We used a non-inferiority design because the high success rate reported in the literature for both devices would make it difficult to demonstrate superiority. With an absolute difference of 15%, we cannot conclude that the Airtraq is non-inferior to fibreoptic. No pre-planned superiority hypothesis was considered in this trial [4]. Although we feel that the only reasonable conclusion was that it was not non-inferior, the data are depicted for anyone to draw their own conclusion.