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During bronchoscopy, awake fibreoptic tracheal intubation and other awake instrumentations of the airway, it is important to provide comfortable, effective and fast topical anaesthesia of the upper airway. Different methods of anaesthetising the airway have been described, but obtaining complete anaesthesia of the airway remains a challenge. We designed a soft mist inhaler device suitable for topical anaesthesia of the airway, the ‘Trachospray’ (Medspray Anesthesia BV, Enschede, The Netherlands) (Fig. 1), featuring a patented spray nozzle unit to produce a specific droplet size. An interventional study was designed to evaluate the clinical performance of the Trachospray in healthy volunteers. Performance was determined by the degree of anaesthesia of the airway and evaluation of its use and comfort level for the subjects while performing awake laryngobronchoscopy. Twenty healthy volunteers (9 men, 11 women, mean (SD) age 23 (0.5) years, mean (SD) weight 72 (2) kg, mean (SD) height 179 (2) cm) inhaled through the Trachospray, which was placed in the mouth. Using a syringe connected to the Trachospray, 2 × 2 ml lidocaine 4% was sprayed through the device into the airway during normal inspiration as the only means of airway anaesthesia. Bronchoscopy using a fibreoptic bronchoscope (Ambu aScope, Ambu, Ballerup, Denmark) was performed by an anaesthetist (JB), aiming to position the distal tip of the bronchoscope in the trachea, after intravenous administration of 2.5 mg midazolam and 5 ug sufentanil. The bronchoscopy was documented by video and used for analysis afterwards. After reviewing the recorded videos, the results can be summarised as follows: Group 1: no response, bronchoscope was easily introduced into the trachea (n = 14, 70%); Group 2: no response after passing through the vocal cords, but a short cough occurred when the tracheal wall was touched by the distal tip of the bronchoscope (n = 2, 10%); Group 3: a short cough occurred when the vocal cords were passed. The coughing stopped when the bronchoscope appeared in the trachea (n = 1, 5%). Group 4: no passage of the bronchoscope through the vocal cords. When vocal cords were touched, they close or a gag reflex occurred. Passage was not immediately possible (n = 3, 15%). Mean (SD) spraying time was 239 (6) s, mean (SD) duration of bronchoscopy was 74 (6) s. Volunteers reported the degree of anaesthesia of the airway as good to very good with a high level of comfort numerical rating score 9, (where 0 = no comfort and 10 = very comfortable) and no pain or fear. Trachospray is a non-invasive technique, in contrast with commonly used invasive techniques such as trans-tracheal injection of lidocaine or superior laryngeal nerve blocks, and was the only method used for applying lidocaine for airway anaesthesia, whereas usually two or more techniques are chosen, for example, lidocaine 10% spray to oropharynx, tonsillar pillars and base of tongue, combined with lidocaine 2% spray above, at and below the vocal cords via an epidural catheter [1] plus, if needed, a spray-as-you-go technique. In conclusion, this interventional study demonstrated that the Trachospray provided a fast, adequate level of anaesthesia of the airway, which allows comfortable awake passage through the vocal cords of a flexible bronchoscope in most volunteers. More research is warranted in order to determine the optimal dose of local anaesthesia and the use of the Trachospray in larger numbers of patients. The study was reviewed and approved by the medical ethical commission of the Radboud UMC, Nijmegen, The Netherlands (NL 70682.091.19; Netherlands Trial Register: NL8187). GvG, MvB and JB have a patent pending for the Trachospray. No other competing interests declared.