Ashok Muniappan
INDICATIONS/CONTRAINDICATIONS
Severe tracheal obstruction that is not correctable by surgical or endoscopic means requires some form of tracheal stenting or bypass for safe and comfortable breathing. A tracheal T-tube is an effective tool to stent airway obstruction that avoids some of the disadvantages associated with a tracheostomy tube or tracheal stent. A T-tube preserves airflow through the nasopharynx, unlike a tracheostomy tube, and allows efficient humidification of the breath and speech. Moreover, a T-tube, by virtue of its sidearm, is not prone to migration and displacement as with a tracheal stent. A T-tube is also less injurious to the trachea and does not extend the tracheal injury as a tracheal stent is prone to do.
A T-tube is temporarily placed for a variety of indications. Temporary stenting of an airway while edema and inflammation resolve sometimes allows eventual decannulation without further intervention. This is more often the exception than the rule as airway obstruction that is severe enough to require intervention is usually not a reversible process. Temporary T-tube placement is also appropriate as a bridge to definitive resection and reconstruction as patients wean from high doses of corticosteroids or recover from reversible conditions such as Guillain–Barré syndrome.
A T-tube also definitively treats airway obstruction in a patient with insufficient normal trachea remaining for reconstruction. It is also effective for palliation of tracheal obstruction by primary or secondary tracheal neoplasms, after conventional modalities have been exhausted. A T-tube is the ideal palliation of tracheal obstruction due to progressive inflammatory disorders such as Wegener’s and relapsing polychondritis, which are not surgically correctable.
The last major indication is management of an anastomotic complication after tracheal or laryngotracheal reconstruction. A T-tube either stabilizes the airway until healing is complete, or it is a bridge to another attempt at repair in several months. Rarely, a T-tube is a permanent solution to a failed tracheal reconstruction.
A T-tube is not appropriate for a patient requiring mechanical ventilation, as the tube does not provide a definitive airway for positive pressure ventilation. A T-tube is also problematic in a patient with obstructive sleep apnea, who may not tolerate closure of the side port at night. A T-tube is generally not appropriate for children or a patient with a small habitus, as the tube is either tolerated poorly or is associated with increased risk of complication. Finally, a patient with a T-tube requires periodic replacement of the tube, as it deteriorates or accumulates endoluminal material. A T-tube must not be placed in a patient with poor access to expert caregivers.
PREOPERATIVE PLANNING
Preoperative computed tomography provides an estimate of the degree and length of tracheal obstruction and what size of T-tube is necessary. Bronchoscopy at the time of T-tube placement is required to directly measure the lesion and confirm what size of T-tube will be accommodated. The proximal limb of the T-tube must be seated below the conus elasticus, when the obstruction extends into the subglottis. A T-tube may be inserted into a pre-existing mature stoma or into a newly constructed stoma.
SURGERY
Positioning
Patients are positioned supine with a bag or roll underneath the shoulders to extend the neck.
Technique
A tracheostomy, if not previously performed, is constructed to lie in the midst of the narrowed and diseased trachea. This is important if future reconstruction is planned, as ideally no normal trachea would be violated during creation of the tracheostomy. Even when there is a pre-existing mature tracheostomy, T-tube insertion is best performed under general anesthesia. Rigid bronchoscopy is performed to dilate any stenosis or to core-out endoluminal tumor and to make precise measurements regarding the location of the stoma, distance between the glottis and the top of the lesion, and the distance between the bottom of the lesion and carina. The tracheal diameter determines the size of T-tube (Fig. 33.1). The location of the stoma and lesion with respect to the glottis and carina determines the length of the proximal and distal limbs (Fig. 33.2). The T-tube is cut accordingly and the ends are sanded to produce a tapered edge, which minimizes granulation formation. A pre-existing tracheostomy may need to be dilated to facilitate insertion of the T-tube.
Figure 33.1 Tracheal T-tube. There is a large selection of T-tubes, to accommodate different tracheal diameters. Some tubes have different diameters for proximal and distal limbs, which is useful for lesions that slowly taper.
Figure 33.2 Tracheal T-tube replacement of standard tracheostomy tube. A pre-existing stoma accommodates a tracheal T-tube. The T-tube restores proximal airflow through the larynx and nasopharynx.
The end of the distal limb is folded and held with a curved clamp and directed into the distal trachea through the stoma (Fig. 33.3A). The clamp then grasps the proximal limb and directs it into the trachea (Fig. 33.3B). The sidearm is pulled to seat the T-tube (Fig. 33.3C). A rigid telescope or a flexible bronchoscope is used to traverse the T-tube to ensure proper deployment. The proximal end of the T-tube must not extend beyond the top of the cricoid cartilage to prevent granulation and fibrosis of the subglottis, which may complicate future reconstruction. The distal limb must extend beyond the bottom of the stenosis without impinging on the carina, which also would promote granulation and scar formation.
Figure 33.3 Insertion of T-tube. The distal limb is grasped with a curved clamp and directed into the distal trachea through the stoma (A). The proximal limb is likewise grasped and directed toward the proximal trachea (B). The side port is pulled to properly seat the T-tube within the trachea (C).
Figure 33.4 Alternative technique for T-tube insertion. An umbilical tape is passed through the side port and proximal limb, grasped through a rigid bronchoscope and brought out through the mouth (A). The limbs of the T-tube are passed into the trachea as in Figure 33.3 (B). The proximal limb is seated by clamping the side port and umbilical tape and pulling on the string emerging from the rigid bronchoscope (C).
Proper deployment of the proximal limb is occasionally difficult. In this situation, umbilical tape is passed through the side port and out the proximal limb (Fig. 33.4A). The tape is then passed into the stoma and brought out the mouth via the rigid bronchoscope. The proximal and distal limbs are inserted into the distal trachea as above (Fig. 33.4B). The tape is then clamped within the side port while the other end emerging from the bronchoscope is pulled taut, seating the proximal limb (Fig. 33.4C).
T-Y and T-L tubes may be fashioned when tracheobronchial disease extends into the mainstem bronchi. Insertion of these tubes can be accomplished with slight modification of technique. In the case of T-Y stents, a bronchoscopic foreign-body forceps can be inserted into the tube to bring the two distal limbs together and guide them into the distal airway (Fig. 33.5).
POSTOPERATIVE MANAGEMENT
The side port of the T-tube is capped once the patient is awake and breathing effectively. Capping ensures humidification of the breath and allows phonation. Breathing through an uncapped side port is avoided, as it dries secretions and leads to inspissated material within the limbs of the T-tube. The patient should be instructed on instillation of saline or mucolytics to minimize buildup of secretions. Instruction on passage of suction catheters and equipment for suctioning at home are essential. An appropriate tracheostomy tube should be available at all times to replace an occluded T-tube.
A fresh stoma is cared for as with a routine tracheostomy. Gentle cleaning of the peristomal skin with saline or hydrogen peroxide is recommended. Granulation tissue around the stoma may require removal or treatment with silver nitrate sticks. T-tubes are replaced at least annually, as the silicone rubber eventually deteriorates and material inevitably builds up within the lumen. Patients are asked to report any increase in work of breathing or wheezing, as this may be a sign that the T-tube requires replacement. A pediatric bronchoscope passed through the glottis or the sidearm of the T-tube is useful to assess patency and proper positioning.
Figure 33.5 Insertion of T-Y tube. A rigid bronchoscopy foreign-body grasper (A) is introduced into the T-Y tube and approximates the two distal limbs (B), which are directed into the distal trachea.
COMPLICATIONS
Total airway obstruction due to inspissated secretions or malposition of the tube is rare but possible. Removal of the T-tube and replacement with a standard tracheostomy tube restores a functional airway. Subglottic or carinal granulation tissue can develop if the limbs impinge on either location. This is avoidable if the limbs are properly sized. Other rare complications include tracheal hemorrhage and T-tube migration.
RESULTS
In our experience, the most common indications for a tracheal T-tube were postintubation stenosis, tracheal burn, and tracheal neoplasms not amenable to resection and reconstruction. Approximately 10% of patients required only temporary T-tube splinting of the airway and eventually underwent decannulation.
When T-tubes were placed after prior tracheal reconstruction, 5 of 32 patients required only temporary placement and underwent decannulation without another operation. Repeat reconstruction was performed in another 5 of 32 patients. The remainder had indefinite management with a T-tube.
Approximately 20% of the patients did not tolerate T-tube placement, most commonly due to airway obstruction. The obstruction generally developed in the subglottis, which is prone to granulation formation. A handful of patients also had difficulty with aspiration, secretions, and tracheobronchitis. T-tubes were less effective in children under the age of 10, in which 5 of 10 suffered T-tube failures.
CONCLUSIONS
Silicone T-tubes are useful in the management of tracheal obstruction not amenable to resection and reconstruction. T-tubes effectively preserve humidification of breathing and phonation. They are less likely to cause tracheal damage beyond what exists, compared to self-expanding or totally indwelling tracheal stents. T-tube placement does not preclude definitive reconstruction and is an important tool for bridging patients who cannot undergo immediate surgery. Periodic maintenance is necessary to ensure proper functioning of the T-tube and avoid complications such as airway obstruction.
Recommended References and Readings
Gaissert HA, Grillo HC, Mathisen DJ, et al. Temporary and permanent restoration of airway continuity with the tracheal T-tube. J Thorac Cardiovasc Surg. 1994;107:600–606.
Gaissert HA, Grillo HC, Wright CD, et al. Complication of benign tracheobronchial strictures by self-expanding metal stents. J Thorac Cardiovasc Surg. 2003;126:744–747.
Kim SC, Kim SH, Kim BY. Successful decannulation of T-tubes according to type of tracheal stenosis. Ann Otol Rhinol Laryngol. 2010;119:252–257.
Nakayama T, Horinouchi H, Asakura K, et al. Tracheal stenosis due to relapsing polychondritis managed for 16 years with a silicon T-tube covering the entire trachea. Ann Thorac Surg. 2011;92:1126–1128.
Wahidi MM, Ernst A. The montgomery T-tube tracheal stent. Clin Chest Med. 2003;24:437–443.