A comparison of two intubation aids in the management of anticipated difficult tracheal intubation

INTERVENTION: The Construct Medical Flexible Tip Bougie (the intervention) will be used to assist with intubation in patients requiring videolaryngoscopy with a CMAC D‐Blade. The Construct Medical Flexible Tip Bougie is an alternative tool, also designed to overcome the "can see, can’t intubate" scenario. This device incorporates a slider, controlled with the thumb and the forefinger, to guide the tip anteriorly, guiding it through the glottis. Furthermore, the ability to also flex the tip posteriorly once past the vocal cords, may avoid the problem of the ETT hitting the anterior tracheal wall and impeding passage of the tube. , Once manipulated into position, the ETT is passed over the bougie, into the trachea. The intubation will be performed by an anaesthetist with at least 3 years anaesthesia experience. A single intubation will be performed for each recruited patient, following the induction anaesthesia. Details of whether or not the patient was successfully intubated with the allocated device will be collected on the case report form, including which, if any, additional airway devices were required. CONDITION: Anaesthesiology ‐ Other anaesthesiology Difficult Intubation; ; Difficult Intubation Respiratory ‐ Other respiratory disorders / diseases PRIMARY OUTCOME: Time taken to successful intubation. [Single time point for each patient. Successful intubation defined as the time from anaesthetist first taking hold of the introducer, to confirmation of successful intubation by visualisation of a capnography trace on the monitor] SECONDARY OUTCOME: Additional adjuncts required to achieve successful intubation (Y/N). This will be reported by the intubating anaesthetist on the case report form following successful intubation[At time of intubation] Anaesthetist rated ease of use of device: recorded on a Likert scale (1‐5) by intubating anaesthetist[Following successful intubation] Number of intubation attempts required, recorded on case report form by the intubating anaesthetist[At time of intubation] INCLUSION CRITERIA: • Adults (>18years) able to provide informed consent • Booked for elective, non‐cardiac surgery • Presence of at least one predictor of increased difficulty of intubation (Any of: prior history of difficult intubation, thyromental distance (<6cm), mouth opening (<2cm), decreased neck extension, Mallampati grade 3+, decreased jaw protrusion)