With advancement in the field of thoracic medicine and development of technology, large numbers of patients are now being treated with tracheal stents. Advancement in stent design and development of both covered and uncovered expandable metallic stents have broadened both indications and durability. As their use has flourished, so have the potential complications associated with them. It is of immense importance for both the ENT surgeons and anaesthetists to be aware of these complications and to be prepared for successfully managing such patients for elective and emergency operations providing a secure airway without compromising the integrity of the airway stent.
Large airway stenting has traditionally been used as palliative treatment for malignant disorders, and now the indications have diversified to include various benign conditions as well. Considering the frequent complication of blockage of tracheal stents, it is questionable whether the use of tracheal stents, especially in proximal trachea, is justified, especially if the patient presents in the emergency with a compromised airway. In such a situation, knowledge of the precise location of the stent and free tracheal segment available for tracheostomy is vital, as the condition of the patient may not permit time for bronchoscopy and bougie-guided placement of the tracheostomy tube. Repeated attempts and failed intubation may lead to various surgical complications, besides damage to the stent. Since the metallic stents are made of stainless steel/titanium mesh, which cannot be cut easily, tracheostomy remains a challenge in these patients.
In patients who are candidates for resection and reconstruction, only temporary endoscopic palliation should be considered in preparation for surgery to allow adequate stabilization of the inflammatory lesion [
A 22- year-old male patient presented to our centre in severe respiratory distress. He had history of corrosive poisoning, one year back, and had been admitted in the ICU for 2 weeks, where he was tracheostomised. 3 months later, he still had difficulty in decannulation and developed left vocal cord paralysis with subglottic edema. At that time, videoendoscopy had revealed more than 70% luminal narrowing, 1 cm below the subglottic area. The stenosed segment, from the lower end of cricoid cartilage up to the tracheostoma, involving the first and second tracheal rings, was opened with a midline incision, and fibrotic scarred tissue was removed. A Montgomery T-tube was placed via the tracheostome. 8 months later, the patient again presented with respiratory distress. This time endoscopy revealed complete obliteration of the tracheal lumen by fibrous tissue. A stainless steel wire mesh stent was placed in the trachea, from the subglottis, to just above the carina. One month following the positioning of tracheal stent, on a visit to this part of the country, the patient presented to our centre with a critically compromised airway. As the patient was being prepared for awake fibre optic intubation, he developed severe respiratory distress.
Emergency tracheostomy was started, and the metallic stent had to be cut open, in order to provide an airway. The mesh was cut with great difficulty leading to considerable manipulations of the stent. Finally, a cuffed tracheostomy tube of I.D. 6 mm was inserted through the stent, and the patient could be ventilated. In the recovery room, the patient complained of chest pain. A postoperative X-ray chest revealed bilateral pneumothorax with right-sided lung collapse with tracheostoma through the stent (Figure
X-ray chest showing tracheostoma in the stent with bilateral chest drains
Granulation tissue blocking the proximal trachea from subglottis to the tracheostomy stoma.
As demonstrated from the above case report, without endoscopic visualisation, airway manipulation in patients with tracheobronchial stents
For patients with distal tracheal stents, a tracheostomy tube can be placed above the stent and carefully guided into the lumen of the stent using bronchoscopes. However, the challenges arise in case of proximal or complete tracheal stents, which get blocked by granulation tissue. It is difficult to provide a secure airway in such cases without damage to the stent, especially if the patient presents in severe respiratory distress.
Complications of tracheal stents [
Covered stents prevent tumour or granulation tissue to proliferate through the stent. However, presence of a covering hampers expectoration of sputum, thus increasing infection. Uncovered stents, though not increasing the risk of respiratory infection, do allow granulation tissue to proliferate within the stent, thus blocking its lumen and causing difficulty in stent removal.
Metallic stents are more prone to develop granulations [
The subglottic airway, with its intact cricoid ring, is not distensible, unlike the proximal trachea. The cricotracheal junction is therefore subjected to greater degrees of motion with head movement [
It is suggested that in patients with tracheobronchial stents, rigid and fibreoptic bronchoscopy should be used if percutaneous tracheostomy is indicated so as to guide the tracheostomy tube through the stent and avoid perforation or dissection of the trachea and formation of a false passage with minimal stent damage. Also, a regular followup is essential to prevent complications from occurring, especially formation of granulation tissue, which may completely block the stent, and does not provide adequate time to the surgeon or anaesthetist to establish a secure airway. Moreover, despite the relative simplicity of stenting techniques, in light of the potential complications suggested, this technique should not be used as a long-term solution for problems in the proximal airway, especially when the stent is placed adjacent to (within 1 cm) the cricotracheal junction.
The optimal treatment of tracheal stenosis remains undefined. Traditionally, tracheal stenosis has been managed by thoracic surgeons and otolaryngologists. Endoscopic procedures are usually performed as a bridge to definitive surgical intervention. Tracheal resection and anastomosis is now accepted as the procedure of choice for tracheal stenosis, with excellent results [
Laser therapy is now recommended only in patients with true contraindications to surgery [