Fibrescope vs Videolaryngoscope for Nasotracheal Intubation

Patients having surgery under general anaesthesia require insertion of a breathing tube to keep the airway open. The technique of inserting a breathing tube through the nose into the trachea (airway) is known as nasotracheal intubation. This is the ideal airway for surgical procedures performed inside the mouth, such as complex teeth extractions and operations on the jaw.

Traditionally, the breathing tube is initially inserted blindly into the nasal cavity. Then, a video laryngoscope (a camera device) or a direct laryngoscope is used to visualise and guide the passage of tube into the trachea. This approach can be associated with difficulty passing the tube and has a high incidence of nasal trauma and nosebleed.

Alternatively, a flexible fibrescope ( flexible camera device) with pre-loaded tracheal tube is passed through the nostril first under vision, gently advanced through the nasal passage and then to the trachea. Once it is correctly placed in the trachea, the breathing tube is railroaded over it. This procedure allows the clinician to visualise the nasal passage and to choose most patent nostril and hence is likely to reduce risk of nosebleed as compared blind passage of tube through the nose. A videolaryngoscope has a camera on the blade that projects the image onto a monitor screen. As this is a rigid device, it can only be inserted through the oral cavity and allows the advancement of tube into the trachea. Both these techniques are currently used in the clinical practice. However, there are no studies to inform anaesthetists whether there are any differences in the incidence of nosebleed.

The investigators therefore wish to do a randomised comparison between flexible fibrescope and videolaryngocope to assess if use of the former is associated with any reduced risk or severity of nosebleed.