Patients Info

The National Centre for Airway Reconstruction

Laryngotracheal Stenosis

Patient Information

Endotracheal intubation injury is the most common cause of acquired laryngotracheal stenosis in the developed world. The incidence is uncertain but estimated at 200 new cases per year in the United Kingdom. Prospective studies have shown some degree of intubation injury in up to 40% of patients who have been ventilated on an Intensive Care Unit. Although the risk of significant airway injury correlates with duration of intubation, there does not appear to be a safe limit and significant injuries have been observed after only 8 hours of intubation in adults and 1 week in children. The incidence of airway stenosis following prolonged ventilation is estimated at 6-10%.

Symptoms related to airway stenosis can be subtle or cause severe shortness of breath (dyspnoea). Subtle symptoms may be mistaken for asthma. Some patients may require surgery to insert a tracheostomy tube in the neck to allow them to breath.

The majority of airway stenoses in the paediatric population are in the subglottis. Most are managed with augmentation using rib grafts. The most severe cases require tracheal or cricotracheal resection and anastamosis. Resection has in the past been the ‘Gold Standard’ in adults as rib grafts have poor survival rates. If this technique is applied to all cases of airway stenosis it has a variable success rate.

Airway injuries differ considerably in pathophysiology and degree and in our series more than 70% have been managed with endoscopic procedures alone. In adults having endoscopic airway surgery, in an appropriate centre, the complication rates and hospital stay are much reduced when compared with resection. Patients not suitable for an endoscopic approach are managed with augmentation techniques and resection is used as a last resort.

Bilateral Vocal Cord Immobility/Palsy

When vocal cord immobility is bilateral a patient may have good voice but experience dyspnoea to such a degree that a tracheotomy is required.. We have had significant success with endoscopic partial posterior cordectomy and partial arytenoidectomy using the CO₂ laser. The resection is usually single sided but can be bilateral. The voice does become ‘breathier’ but remains functional. If the cords have become fixed due to inter-arytenoid webbing then this can usually be corrected surgically. Re-innervation following recurrent laryngeal nerve injury holds hope for the future but to date has not been successful for airway compromise. Laryngeal pacing techniques are also being researched.

Inflammatory and Immune Diseases

Several inflammatory diseases may affect the mucosa or connective tissue of the airway resulting in stenosis. Wegener’s granulomatosis is perhaps the most common. This is a condition of unknown aetiology characterised by a vasculitis involving the respiratory tract, kidneys, skin, eyes and joints. About 15% will have laryngotracheal involvement although the nose and ears may be involved in up to 75% of cases. Biopsies cannot always be differentiated from inflammation due to other causes. The most useful serological test is cytoplasmic antinuclear cytoplasmic antibody (c-ANCA) which is positive in over 90% of patients with active disease. Corticosteroids are the mainstay of treatment in combination with other immune modulating drugs. Subglottic and tracheal stenosis can be managed with intralesional steroid injections, radiate laser cuts and dilatation. We have successfully extended this technique to the treatment of bronchial lesions. Even during periods of disease relapse our advice is to try and avoid stenting of the airway or tracheostomies as they encourage scarring. In patients who have had tracheostomies inserted we have been successful in removing these through surgery.

Sarcoidosis is a granulomatous (inflammatory) condition of unknown cause. Although there is no cure, corticosteroids may control the rate of disease progression. The larynx is involved in 1-5% of cases. The supraglottic larynx tends to be affected more often than the subglottis. The laryngeal lesion is usually a pale pink, edematous swelling that can pedunculate into the airway and produce stridor. Intralesion steroids and carbon dioxide laser debulking of laryngeal lesions can be effective in restoring the airway.

Amyloidosis is a group of disorders characterised by acellular deposition of proteinaceous material in one or many organs. Primary amyloid is not associated with other medical conditions and may be localized to one specific site or generalized throughout the body. Secondary amyloidosis is associated with chronic inflammatory disorders such as tuberculosis or rheumatoid arthritis. Biopsy specimens appropriately stained by a pathologist are usually diagnostic. Laryngeal involvement is extremely rare and presents as a tumour mass or nodules which can usually be removed endoscopically. These procedures can be repeated to maintain an airway and rarely is laryngeal or tracheal involvement fatal.

Relapsing polychondritis is an episodic inflammation of the cartilaginous structures of the body resulting in their destruction and replacement with scar tissue. The organs involved are principally the ears, nose and peripheral joints and also the tracheobronchial tree. The pathogenesis is unknown but is likely to be auto-immune. Diagnosis is on clinical grounds and nearly half of the patients have layngeal involvement. Treatment is based on prolonged corticosteroid therapy which is increased during disease flare up. Prognosis is variable but a number of patients end up with a longterm tracheotomy tube.

Mitomycin C

Mitomycin C is derived from the bacterium streptomyces caespitosus and has been used as a chemotherapeutic agent for the treatment of cancers. In low concentrations it has also been shown to selectively inhibit fibroblast activity and prevent airway scarring in animal studies. There are few studies supporting its use in the human model and long-term side effects are not known. In our experience applied topically following endoscopic surgery it can reduce the tendency to re-stenose in some patients.

Idiopathic subglottic stenosis

This is a slowly progressive, inflammatory and fibrotic airway stenosis that is unremitting and affects almost exclusively women. There are only a few hundred cases in the world literature and the condition can occur at any age post puberty. The diagnosis is one of exclusion and the patient must not have been intubated, received neck trauma or had a significant respiratory tract infection in the preceding two years. Patients must also be investigated for acid reflux from the stomach and auto-immune disorders including Wegener’s granulomatosis ruled out. It is not unusual for these patients to be treated for asthma until diagnosis is made. Diagnosis can be made from appropriate respiratory function tests, radiological imaging or bronchoscopy.

The disease usually involves the subglottis and first two tracheal rings. The airway in these patients appears to have a heightened reactivity to any kind of trauma. Aggressive treatment with lasers or trauma from hard laryngeal stents can lead to more marked laryngotracheal stenosis. A conservative gentle approach is recommended. Most patients respond to radial laser incisions and dilatation with mitomycin application. Stenosis recurs usually over a period of 6 to 12 months at which time surgery can be repeated. Some surgeons recommend primary cricotracheal resection but the high reported success rates have not always been repeatable in other units. We manage most cases of idiopathic subglottic stenosis endoscopically. Often patients are referred with more significant stenosis following previous aggressive surgery and may require augmentation or resective surgery if endoscopic techniques fail.