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Laryngotracheal stenosis (LTS) is a narrowing of the upper airway between the larynx and the trachea with potentially devastating consequences, including respiratory failure, cardiopulmonary arrest, and death. The upper airway is constituted by the larynx, glottis, subglottic region, and trachea. The trachea is a cylindrical-shaped tube with an anterior cartilaginous wall formed by c-shaped rings and a posterior membranous wall. The trachea branches off into the right and left mainstem bronchi at the carina, which is located at the level of the fourth thoracic vertebra (T4). This activity reviews the etiology, pathophysiology, clinical presentation, diagnosis, management, and complications of laryngotracheal stenosis. It also covers the role of the interprofessional care team in the treatment of these patients. Objectives: Identify the etiology of laryngotracheal stenosis. Review the appropriate evaluation of laryngotracheal stenosis. Outline the treatment options available for laryngotracheal stenosis. Describe interprofessional team strategies for improving care coordination and communication to advance laryngotracheal stenosis and improve outcomes. Access free multiple choice questions on this topic.

Laryngotracheal stenosis (LTS) is a narrowing of the upper airway between the larynx and the trachea with potentially devastating consequences, including respiratory failure, cardiopulmonary arrest, and death. The upper airway is comprised of the larynx, glottis, subglottic region, and trachea. The trachea is a cylindrical-shaped tube with an anterior cartilaginous wall formed by C-shaped rings and a posterior membranous wall. The trachea branches off into the right and left mainstem bronchi at the carina, which is at the level of the 4th thoracic vertebra (T4). Laryngeal stenosis may occur as a result of trauma, related to endotracheal intubation, or due to a neoplasm, autoimmune, or infectious process. It can be asymptomatic or can lead to symptoms of upper airway obstruction. Laryngeal narrowing from any cause requires a multidisciplinary approach to management, including, but not limited to, pulmonologists, intensivists, otolaryngologists, and gastroenterologists, as well as speech-language pathologists and cardiothoracic surgeons. Determining the etiology of LTS is critical, as it informs management and provides prognostic information for the patient.

Several etiologies are associated with the development of LTS.[1] Recognized causes of laryngeal stenosis include: iatrogenic (ex, complication of endotracheal intubation), autoimmune, infectious, neoplastic, traumatic, and idiopathic. Autoimmune diseases, including systemic lupus erythematosus, rheumatoid arthritis, vasculitis, sarcoidosis, and scleroderma, among others, can cause LTS. Infectious causes include bacterial tracheitis, viral papillomatosis, and tuberculosis. Neoplasms of the larynx or trachea can also cause airway narrowing, with squamous cell carcinoma and adenoma being the most common malignancies in this setting.[2] Direct injury to the trachea by trauma, inhalation burns, or radiation is 1 of the causes of traumatic LTS.[3] Acute laryngeal injury has been described as a potential component of post-intensive care syndrome.[4] Common post-intubation complications include transient dysphonia, dysphagia, and sore throat for patients undergoing surgery. However, these complications present more markedly in critically ill patients. Endotracheal tubes can cause laryngeal injury through direct compression of the posterior glottic mucosa, which may eventually progress to fibrosis and scarring, resulting in stenosis.

There is no clear data on the epidemiology of LTS, as it is difficult to regard this disorder as a single entity given the range of causes. Tracheal stenosis may occur in up to 30% of patients with tracheostomies, though many factors can contribute, depending on the patient's comorbidities, the indication for, and duration of, the tracheotomy.[5]

The narrowest part of the adult airway is at the subglottic space at the level of the cricoid cartilage, which extends from the inferior part of the vocal cords to the lower part of the cricoid cartilage.[3] This area is only a few centimeters in length but can be commonly injured during endotracheal intubation, as the endotracheal tube makes contact with the posterior aspect of the subglottic space during intubation. Prolonged intubation can also cause LTS when cuff pressure exceeds mucosal capillary perfusion pressure (approximately 35 mmHg), leading to ischemia, ulceration of the posterior mucosa, and subsequent fibrotic strictures.[6] Among patients with underlying autoimmune diseases, granulomatosis with polyangiitis (formerly known as Wegener granulomatosis) is the most commonly associated with LTS, characterized by necrotizing granulomatous inflammation of the upper airways, with vasculitis perpetuating fibrotic changes and stenosis.[7]

Evaluating a patient with suspected LTS includes a detailed history and physical examination. History should include any prior endotracheal intubations and their durations, a history of infection, autoimmune disease, vasculitis, trauma, or surgery, as well as current symptoms. The most common symptoms of LTS, regardless of etiology, include dyspnea, stridor, hoarseness, and cough. In the acute, emergent setting, a physician may not have sufficient time to obtain such detailed information; in such cases, the physical examination becomes crucial. One must be able to identify inspiratory stridor, which is most commonly neck-based and associated with cough and dyspnea. If the patient has extrathoracic stenosis, they may present with hoarseness, inspiratory wheezing, stridor, and nonproductive cough. Intrathoracic stenosis is evident with difficulty in expiration and lying in the recumbent position. There may be reduced ability to clear secretions, as well as wheezing mimicking asthma that does not respond to bronchodilators.[8] Localization of the stenosis is difficult on clinical grounds alone.

LTS can be evaluated by laryngoscopy or bronchoscopy. The clinician may obtain a computed tomography scan of the neck in severe cases in which the obstruction does not allow for direct laryngoscopy or in patients who have a traumatic injury to the trachea, and in planning for surgical treatment. Computed tomography scans may demonstrate artificial extratracheal stenosis, such as in a massive goiter, owing to the trachea's dependent position during imaging.[2] Performing spirometry on these patients helps establish a baseline and monitor their status over time.[9] There are 3 classification systems based on anatomic characteristics that are derived from intraoperative findings. The Cotton-Myer classification is based on percent stenosis (1 = <50% obstruction; 2 = 51% to 70% obstruction; 3 = 71% to 99% obstruction; 4 = Complete obstruction). The Lano classification is based on subsite involvement (1 = 1 subsite involvement; 2 = 2 subsite involvement; 3 = 3 subsite involvement, with the subsite meaning the glottis, subglottis, and trachea). The McCaffrey classification is based on the length of stenosis (1 = subglottis or trachea <1 cm; 2 = subglottis >1 cm; 3 = subglottis and trachea >1 cm; 4 = any lesion involving glottis). Percent stenosis is important with regard to prognosis, individualized treatment planning, and risk stratification of tracheostomy dependence. Patients with grade 3 and 4 stenosis in the Cotton-Myer classification were found to be tracheostomy dependent compared to patients with grade 1 and 2. According to the Lano classification, greater subsite involvement was associated with a higher risk of tracheostomy dependence and a higher stage in the McCaffrey classification. In adult LTS, the Lano and McCaffrey classifications are more precise than the Cotton-Myer scale.[1]

Overview The management of LTS is complex, as it may involve multiple procedures and may be associated with restenosis in certain cases. Treatment goals are to maintain airway patency, reduce the number of procedures required, and achieve decannulation in patients with tracheostomy. Unfortunately, there is no standard guideline for the approach to and management of LTS to date. Most treatment modalities have been described in studies across various specialties in the medical literature. Treatment options for LTS include endoscopic dilatation, surgery, stent placement, laser therapy, or immunosuppression to restore airway patency, depending on the underlying etiology and the degree and complexity of stenosis.[10] Bronchoscopic Approach Bronchoscopy may be used for mechanical dilation, laser therapy, and stenting to treat LTS. These treatment modalities may have limited use in subglottic stenosis due to anatomical challenges. Dilation or laser treatment is an option for strictures or granulomas; however, these procedures are at risk of recurrence. Stent placement can migrate and cause a larger airway injury. A laser is used cautiously for subglottic stenosis due to the risk of damaging the cricoid cartilage, which is the site of the laryngeal nerves and plays a role in vocal cord function. Several studies have shown that laser therapy and stenting achieve success rates below 20%.[3] Bronchoscopic therapy has been used in cases where the patient is not a surgical candidate to palliate symptoms. Endoscopic Mechanical Dilation Endoscopically guided dilation is performed using several devices, including gum-tipped bougies, endotracheal tubes, and balloon catheters. It could be performed in the outpatient setting for a selected group of patients. This route yields more favorable voice-preservation outcomes than stenosis less than 2 cm from the vocal folds or stenosis at multiple levels. Endoscopic dilation should be the first-line treatment for simple stenosis, whereas more complex stenoses require an interprofessional approach and possible surgical evaluation. The average patient may be able to remain free of subsequent dilations for approximately 1 year.[11] Tracheal Stenting

Endoscopically guided dilation is performed using several devices, including gum-tipped bougies, endotracheal tubes, and balloon catheters. It could be performed in the outpatient setting for a selected group of patients. This route yields more favorable voice-preservation outcomes than stenosis less than 2 cm from the vocal folds or stenosis at multiple levels. Endoscopic dilation should be the first-line treatment for simple stenosis, whereas more complex stenoses require an interprofessional approach and possible surgical evaluation. The average patient may be able to remain free of subsequent dilations for approximately 1 year.[11] Tracheal Stenting Tracheal stenting is a palliative option for patients with advanced and unresectable cancer-causing airway obstruction. As noted above, stenting is a challenging and high-risk procedure that requires a risk-benefit discussion with the patient. Higher preoperative performance status correlates with better patient outcomes. A Japanese study by Matsuo et al aimed to clarify indications for stent placement, including severe central airway obstruction with dyspnea and flow limitation on a flow-volume curve, a prognosis that is prolonged by stent placement, and intact peripheral airways and lungs.[12] Preoperative Assessment Several preoperative assessments may aid prognostication and the selection of a suitable treatment modality. The patient should be screened for methicillin-resistant Staphylococcus aureus (MRSA) colonization at least 2 to 3 weeks before possible surgery, as MRSA colonization may increase the risk of postoperative complications. If patients test positive for MRSA, they should be treated prophylactically with a 3-day course of double-strength trimethoprim-sulfamethoxazole orally and mupirocin intranasally, and with 14 days of intravenous vancomycin postoperatively until all drains have been removed. Before pursuing further treatment, patients should also undergo a swallowing evaluation using a fiberoptic endoscopic evaluation of swallowing or a modified barium swallow study to determine the optimal route for postoperative nutrition. Fiberoptic endoscopic evaluation of swallowing also assesses vocal fold mobility and the extent of the stricture.[13] Open Surgery

Several preoperative assessments may aid prognostication and the selection of a suitable treatment modality. The patient should be screened for methicillin-resistant Staphylococcus aureus (MRSA) colonization at least 2 to 3 weeks before possible surgery, as MRSA colonization may increase the risk of postoperative complications. If patients test positive for MRSA, they should be treated prophylactically with a 3-day course of double-strength trimethoprim-sulfamethoxazole orally and mupirocin intranasally, and with 14 days of intravenous vancomycin postoperatively until all drains have been removed. Before pursuing further treatment, patients should also undergo a swallowing evaluation using a fiberoptic endoscopic evaluation of swallowing or a modified barium swallow study to determine the optimal route for postoperative nutrition. Fiberoptic endoscopic evaluation of swallowing also assesses vocal fold mobility and the extent of the stricture.[13] Open Surgery Open surgery is offered in patients with Myer-Cotton grade 3 or 4, loss of cartilage, or stenosis longer than 1 cm. Open surgery is an option in cases with hard tissue and scar tissue greater than 1cm in length. Surgical cases have higher success rates, whereas endoscopic procedures require more repeat interventions. Open surgery may be divided into laryngotracheal resection with reanastomosis or laryngotracheoplasty using native tissue or tissue grafts.[13] Laryngotracheal resection with reanastomosis A systematic review by Lewis et al found that laryngotracheal resection with anastomosis was associated with a lower need for additional surgeries and a higher rate of decannulation than endoscopic procedures. They also found that patients with idiopathic stenosis required less additional surgery compared to patients with LTS due to trauma or intubation.[14] Laryngotracheoplasty Laryngotracheoplasty encompasses surgical techniques that employ single- or multistage approaches, using various luminal grafts or tracheal stents.[15] Outcomes are typically favorable, with a high rate of decannulation. They also have low postoperative complications, which include granulation tissue and glottic edema. They may be treated with a short course of dexamethasone for 24 to 48 hours, along with diuresis and elevation of the head of the bed.[16][17] Montgomery T-Tube

Laryngotracheoplasty encompasses surgical techniques that employ single- or multistage approaches, using various luminal grafts or tracheal stents.[15] Outcomes are typically favorable, with a high rate of decannulation. They also have low postoperative complications, which include granulation tissue and glottic edema. They may be treated with a short course of dexamethasone for 24 to 48 hours, along with diuresis and elevation of the head of the bed.[16][17] Montgomery T-Tube The Montgomery T-tube is placed through the trachea’s anterior wall distal to the anastomosis. It provides a stable airway for prolonged periods (at least 6 months) until the consideration of decannulation, or permanently in inoperable cases.[2][9][18] Adjunctive Treatments Several adjunctive treatment options are currently used for the treatment of LTS. A review of the literature suggests the use of adjunctive treatments such as mitomycin C, steroids, and proton pump inhibitors. Mitomycin C Mitomycin C is a chemotherapeutic agent used topically for 4 minutes after incision. It works as an alkylating agent that inhibits cell division, protein synthesis, and fibroblast proliferation, ultimately decreasing the formation of scar tissue. It has been reported that this may be a therapeutic option for thinner stenoses; however, restenosis may occur at similar rates at 5 years with or without reapplication.[19] Steroids For patients undergoing dilation, local or systemic corticosteroids administered orally have favorable evidence in current data, with greater success noted in stenoses greater than 1 cm.[20][21]

Some differential diagnoses that must be considered in the evaluation of LTS include the following: Angioedema Asthma Epiglottitis Esophageal tumor Foreign body aspiration Gastroesophageal reflux disease Mediastinal mass Retrosternal goiter Subglottic web Tracheomalacia Vocal cord dysfunction [22]

Overall prognosis is excellent for patients with idiopathic LTS who undergo definitive surgery. Prognosis in other etiologies is determined by the clinical course of the underlying disease that causes LTS.

Acute LTS (eg, post-extubation LTS) may result in respiratory arrest if not promptly and correctly identified. In idiopathic LTS, complications include changes in voice, tracheostomy dependence without the ability to decannulate, and the requirement for multiple procedures. Tracheostomy decannulation is a target goal of open surgery. Approximately 63-95% of patients who undergo open surgery are successfully decannulated. However, patients with grade 3 or 4 stenosis (Myer-Cotton scale), diabetes, gastroesophageal reflux disease, and/or body mass index greater than 30 may have higher rates of tracheostomy dependence. Additionally, open surgery may be complicated by dysphagia due to injury to the recurrent laryngeal nerves or the use of a stent to maintain airway patency.[9] A prospective study by Bibas et al in the Journal of Thoracic Disease found that quality of life in patients with benign tracheal stenosis (eg, endotracheal intubation, not amenable to surgical treatment) is severely impaired.[23] Health-related quality of life entails the physical and mental welfare of the patient and their family. This study included patients with Montgomery T-tubes, endotracheal silicone stents or tracheostomy, and the ability to fill out a questionnaire. They excluded patients with chronic comorbidities, such as chronic obstructive pulmonary disease, advanced heart failure, and renal failure.

Patients with LTS typically require multiple specialists, depending on the clinical stage at presentation. In the acute setting, for example, when a patient is noted to have post-extubation stridor, an intensivist is usually the primary consultant, with additional support from an anesthesiologist if the patient requires reintubation of a difficult airway. Ear, nose, and throat specialists, trauma surgeons, and interventional pulmonologists may also need to intervene. Interventional pulmonologists are essential for stent placement, whereas cardiothoracic surgeons may be necessary for surgical approaches in chronic or recurrent cases. Whenever such patients undergo interventional procedures, coordination with the anesthesiology team is essential, as advanced airway management, such as apneic techniques or jet ventilation, is routinely required.[1]

Frequently, patients are unable to be informed about the need for endotracheal intubation and potential complications, such as LTS, because it occurs in an emergent setting. In cases where patients have a history of autoimmune diseases and may have LTS, they should be counseled by their physician regarding what signs and symptoms they should not ignore and seek immediate medical attention, especially if they have had a previous episode of LTS. Additionally, patients affected by LTS, especially those of idiopathic etiology, may benefit from online forums where they can connect with other patients similarly affected to share information, experiences, and emotional support.[24]

LTS is a rare condition that may result from different etiologies and has serious health implications. Physicians need to consider it in patients presenting with dyspnea, stridor, wheezing, and/or changes in voice. Making the diagnosis is crucial to involve the necessary teams to treat the patient, including a critical care physician if there is concern for airway patency and acute airway protection. In more insidious or chronic cases, it is prudent to involve an interventional pulmonologist and/or an otolaryngologist for bronchoscopy or laryngoscopy to facilitate further evaluation. A rheumatologist may be helpful if LTS has been deemed to have an autoimmune etiology. A cardiothoracic surgeon should be consulted if surgery is required, or a general surgeon for cases involving tracheostomies. Patients with speech changes may benefit from the services of speech-language pathologists. In hospitalized patients, respiratory therapists usually assist with tracheostomy care as needed.