VVAS TUTORIAL

Tritube for tracheal resection

A tutorial by
Jo Mourisse MD PhD*
Guido Van Der Reijden**

Alberto Grassetto MD***

Tritube may represent an ideal approach to tracheal resection for its small 4.4mm outer diameter. It enables gentle awake intubation in case of difficult airways and sweet awakening. Moreover, no field intubation is needed. Finally, fiberoptic evaluation is made easier.

* Radboud University Medical Centre, Nijmegen (NL)
** Ventinova Medical, Eindhoven (NL)
*** Vittorio Veneto Hospital (IT)

Materials

  • Evone ventilator (including cartridge, breathing tubing, airway adapter and HME filter)
  • Tritube - OD 4.4mm
  • Ventrain (highly recommended)
  • Flexible bronchoscope
  • Laryngeal mask (e.g. i-gel)
  • 10 cc syringe
  • (Video)laryngoscope
  • Nasopharingeal cannula*
  • Xylometazoline (Otrivin)
  • Cuff pressure manometer
  • Fiberscope
  • Guidewire**
  • Tegaderm***
* optional, ** if awake intubation is planned, *** in case of need of reducing cuff size (see managing of low tracheal resection)

Preparation
Planning airway management in advance

It’s very important to discuss with the surgeon the airway management plan. A precise knowledge of the site of resection, level, grade and extension of the obstruction is fundamental.

It could be useful to perform a pre-operative evaluation with a flexible bronchoscope of the trachea’s anatomy.

Subsequently, it will be chosen if the patient can be intubated after induction of anesthesia or if it’s safer to proceed to awake intubation.

Consider the use of HFNC (High-flow Nasal Cannula) during pre-oxygenation of a patient with predicted difficult airways, to increase the apnoea time.

Intubation

Difficult airway (Awake intubation)

Awake nasal intubation: Tritube in combination with a guidewire

  • Administer local anesthesia as the institution protocol to guarantee optimal analgesia
  • Place HFNC (High Flow Nasal Cannula) 40L/min (suggested)
  • ·Advance the flexible bronchoscope through the nose into the trachea and pass the surgical site
  • ·Advance a guidewire through the working channel (sideport) of the flexible bronchoscope
  • Withdraw the fiberscope and fixate the guidewire at the mouth with your hand.
  • Advance Tritube over the guidewire under fibroscopy (second nose hole).

When Tritube is at the desired position, perform the following steps:

  • Preoxygenate by means of mask ventilation (accept small leakage due to Tritube)
  • Perform induction; including complete NMB
  • When patient sedation and NMB is deep enough:
  1. Inflate cuff to 30-35 mbar (so that tip Tritube is centered; not against the trachea wall).
  2. Flush firmly both ventilation and pressure lumen of Tritube with air, to remove possible secretions picked up during intubation.
  • Connect Evone and start FCV

NOTE: If mask ventilation fails/insufficient and/or support is desired during induction, consider to start FCV with deflated cuff. This result in leakage, causing that PEAK level might not be reached. Evone remains however insufflating under continuous pressure measurement control AND additional intermittent pressure control.

Intubation (after induction)

  • Nasal intubation results in better fixation, which reduces the risk of upwards moving cuff Tritube during surgery.
Two options:
  1. In combination with nasopharyngeal cannula (spray inside thoroughly)
  2. Directly. In advance, administer drop-wise Otrivin (xylometazoline) inside the nose.
  • When Tritube is at the desired position, perform the following steps:
  1. Inflate cuff to 30-35 mbar (so that tip Tritube is centered; not against the trachea wall).
  2. Flush firmly both ventilation and pressure lumen of Tritube with air, to remove possible secretions picked up during intubation.
  • Connect Evone and start FCV

NOTE: The patient MUST have a complete neuromuscular block (NMB) before initiating ventilation with Evone in FCV mode. The monitoring of neuromuscular block with TOF should be considered before intubation;

  • Check with the flexible bronchoscope the position of Tritube.

NOTE: Performing flexible bronchoscopy can be challenging during surgery, because of the presence of the surgical drapes/towels. Therefore after intubation Tritube, it can be considered to place a laryngeal mask which can be used as working channel to facilitate the flexible bronchoscope. The laryngeal mask will be placed alongside of Tritube

When a laryngeal mask does not fit, a mayo tube can be considered for this purpose.

TIPS: Very high tracheal resection (cricoid involved in resection)

When the surgical site is high (close to the vocal cords), the surgical view can be worsened due to collapsing structures. Normally this is prevented by the size of a conventional endotracheal tube, however Tritube is too thin for this. To prevent this, an additional tube could be placed (for example tube size 9) to act as a stent in parallel to Tritube. This can then also be used as working channel for the flexible bronchoscope (instead of laryngeal mask/mayo as described above).

Intraoperatively


Check location resection

Perform fibroscopy to confirm the exact location of the area that must be resected. From the outside it can be challenging for the surgeons to determine the exact location. It can therefore be considered to open the trachea under fiberoptic guidance.


Check tracheal sutures

Before closing the skin, the sutures of the trachea must be checked with a flexible bronchoscope for leakage. This is usually done by building up pressure and check for bubbles.
- Deflate cuff Tritube. Built up pressure (e.g. by means of inspiration hold) and close hereby mouth and nose
- When laryngeal mask is used: create pressure through laryngeal mask, whereby cuff Tritube remains inflated.


An i-gel can be used as working channel to make easier the introduction of flexible bronchoscope. Of course, it is placed after the intubation with Tritube.

During surgery the small size of Tritube enables the surgeon to work around the tube, avoiding field intubation.

TIPS:  at the beginning of resection it can be considered to deflate the cuff and switch Evone to HFJV to avoid cuff damage. When the right position of the cuff is found, inflate the cuff and switch again to FCV mode. NOTE: HFJV could be annoying to the surgeon so it's suggested to use this mode for short periods.


Low tracheal resection
(via right thoracotomy or sternotomy)

Length cuff + tip Tritube = 6,5 cm

Mean length left main bronchus = 4,5 cm

The tip of Tritube will end in the junction left upper lobe / left lower lobe when Tritube is placed in the left main bronchus: so that ventilation is then not possible. Consider the following:

  • Reduce the cuff of Tritube by wrapping it partially with a strip of sticky tape, for example Tegaderm.
  • Place the adapted Tritube in the left main bronchus. Use if necessary, a guidewire of the Arndt bronchial blocker.

NOTE: Due to the angle to the left main bronchus it can happen that the tip of Titrube ends in the bronchial wall (also when cuff is inflated). Check with the fiberscope if the murphy eye of Tritube is at ‘the free /open side’. Otherwise turn Tritube.

DISCLAIMER: The alteration of the cuff size is not approved by the Tritube manifacturer, so the decision to modify in such way the tube is under user's responsability

Awakening / extubation

  • Extubation is a very delicate moment in these patients, so keep the time needed to a sweet awakening. Switching TIVA-TCI to dexmetedomidine may be useful in this setting.
  • Reversal of NMB and monitoring with TOF is recommended
  • Deflate cuff Tritube in time to prevent that the patient tries to breath himself through the high resistance Tritube. This result in leakage, causing that Peak level might not be reached. However, Evone continues insufflating under pressure measurement control AND additional intermittent pressure control. This support is adequately during awakening.
  • Because of Tritube is very tolerated, with the patient arousing while still intubated, it may be considered to use fibroscope to look vocal cords movement.

NOTE: Consider to leave Tritube in situ in the immediate recovery period if problems are suspected (e.g. vocal cords palsy)