Impact of Tracheal Tube Fixing Site on Its Mobility During Head Mobilization

Tracheal intubation is the only technique to ensure airway protection, meaning preventing aspiration, and providing mechanical ventilation during general anesthesia (GA). This is an extremely frequent procedure. After intubation, the head of the patient is often moved as the patient is positioned for the surgical procedure (ENT, thoracic and abdominal surgeries, lateral or prone positioning…). This may even happen several times during the same procedure. It is well demonstrated that these head movements are responsible for secondary shifting of the tube (1-9). This can cause accidental extubation or selective bronchial intubation.

The anesthesiologist secures the tube with tape to prevent secondary displacement of the tracheal tube. The two most common sites to tape the tube on patient's face are the maxilla, because it is a fixed spot on the face, and the mandible, because its mobility coming from the temporomandibular joint may allow a better interlock with the larynx.

There is no study and no recommendation about the best site of tape. Both techniques are commonly used, depending on the anesthesiologist's preference.

Investigators designed a, controlled study in Brest university hospital to compare two groups by cross-over intervention (one group "maxilla fixing then mandible fixing" and one group "mandible fixing then maxilla fixing").

The population is composed of adult patients undergoing bronchoscopy or endobronchial ultrasound under GA and after tracheal intubation. The bronchoscope allows a permanent control of the tracheal tube's position, and the possibility of shifting it without compromising patient security, which is not possible in other daily surgical procedure.

Statisticien estimate that the total number of patients to include is 36. In order to avoid a sequence effect, the order of the fixing technique will be randomized. Every patient will be its own control as there is a cross over-design.

The main outcome is the maximal amplitude of the tracheal tube shifting when the head is bended on the chest and extended in the back, controlled by bronchoscopy with each fixing technique.

The anesthesiologist investigator will use the first fixing site according to the patient's randomization group. Then, he will display an opaque cover around the tracheal tube, so that the operator, who will measure the tube displacements, will stay blind. As the intervention is performed under GA, the patient will also be blind. The same procedure will be performed after the second fixing site is used, before the end of the intervention.

Inclusion criteria

• Adult
• Bronchoscopy or endobronchial ultrasound
• General anaesthesia
• Tracheal intubation

Exclusion criteria

• Patient incapable of consenting or with a legal guardian or declining participation
• Forbidden or impaired cervical mobility (less than 80°)
• Mouth opening less than 35 mm
• Moustache or Beard