Medical disclaimer: This page is for educational purposes only. It does not replace the advice of a qualified doctor. If you are experiencing breathing difficulty, please consult a medical professional promptly. Last reviewed May 2026 by Dr. Kunal Waghray, MD DM DNB MNAMS EDRM.
What Is Tracheal Stenosis?
A patient comes home from the ICU after a difficult COVID-19 admission. Weeks pass, then months. The breathlessness that started after discharge does not go away. A doctor prescribes inhalers. The inhalers do not help. The breathing keeps getting harder on stairs, in the morning, even on short walks. Another doctor says it might be adult-onset asthma. More inhalers, no improvement.
Eventually, a chest physician refers the patient for a bronchoscopy. The scope reaches the windpipe and stops. The trachea has narrowed to less than a third of its normal opening. This is not asthma. This is tracheal stenosis.
If this story sounds familiar, this page explains what tracheal stenosis is, why it happens, and what the path to diagnosis looks like.
What Is the Trachea, and What Does “Stenosis” Mean?
The trachea is the tube that carries air from your throat down to your lungs. It sits in the front of your neck and chest, is roughly 10 to 12 centimetres long, and is held open by rings of cartilage. Every breath you take passes through this single tube. There is no alternative route.
“Stenosis” is a medical word for narrowing. When scar tissue, granulation tissue, or external compression reduces the inner diameter of the trachea, each breath must pass through a smaller opening. Think of the difference between breathing through a full-width tube and breathing through a straw.
The body adapts to mild narrowing without obvious symptoms. Noticeable breathlessness often appears only when the tracheal lumen has narrowed by 50 to 70 percent of its normal diameter. This is why many patients feel well at rest but struggle badly during any physical effort.
What Causes Tracheal Stenosis?
Post-intubation and post-tracheostomy stenosis
The most common cause in India and worldwide. When a patient is placed on a ventilator, a tube is passed through the mouth or nose into the trachea. The inflatable cuff at the tip of that tube holds the airway sealed. If cuff pressure is too high or intubation is prolonged, the tracheal lining loses its blood supply and develops ischaemic injury. Scar tissue forms as the wound heals, and the lumen narrows. During the COVID-19 pandemic, a large number of patients across India needed prolonged ventilation. Research published in the Indian Journal of Surgery documented complex post-intubation tracheal stenosis specifically in COVID-19 patients (PMC9261125). Symptoms typically appear six weeks to three months after ICU discharge.
Post-TB tracheal stenosis
An important and often overlooked cause in India. Active TB in the airways causes inflammation, ulceration, and fibrotic scarring as it heals. That scarring can narrow the subglottis or upper trachea significantly. Post-TB stenosis should be considered in any patient with a history of pulmonary or endobronchial TB who develops progressive breathlessness, sometimes years after completing treatment.
Idiopathic subglottic stenosis
In some patients, tracheal or subglottic narrowing develops with no identifiable prior injury or illness. This is called idiopathic subglottic stenosis (ISS). It occurs predominantly in women, often in their thirties and forties, and its cause is not fully understood. Because there is no obvious trigger, diagnosis is frequently delayed.
Trauma, malignancy, and autoimmune causes
A direct blow to the neck or larynx can damage tracheal cartilage and lead to scarring. Tumours arising within the trachea, or pressing on it from outside, can narrow the lumen. Autoimmune conditions, particularly granulomatosis with polyangiitis (GPA, formerly Wegener's granulomatosis), can cause tracheal or subglottic inflammation that eventually produces fibrous narrowing.
Symptoms: Why Tracheal Stenosis Is Often Mistaken for Asthma
The two most common symptoms of tracheal stenosis are breathlessness on exertion and a high-pitched breathing sound called stridor. Stridor is heard mainly on breathing in, whereas the wheeze of asthma is heard mainly on breathing out. That distinction is easy to miss in a busy clinic, especially because stridor can be faint in the early stages.
Patients often describe their breathing as fine at rest but difficult when climbing stairs or walking at pace. Some describe a whistling or squeaking sound on inhalation. A change in voice quality or persistent hoarseness can appear when the narrowing involves the subglottis, which sits just below the voice box.
Stridor vs asthma wheeze: a clinical distinction
Tracheal stenosis
- Sound heard mainly on inhalation
- Fixed structural narrowing
- Does not respond to bronchodilators
- History of intubation, TB, or ICU care
Asthma
- Wheeze heard mainly on exhalation
- Diffuse small-airway narrowing
- Responds to salbutamol or steroids
- Episodic, often allergic triggers
The misdiagnosis rate for tracheal stenosis is high. Multiple documented cases show patients using bronchodilators for months before the real cause is identified. The key clue is that asthma treatment does not work. When breathlessness persists despite appropriate inhaler therapy, and when there is a history of intubation, tracheostomy, or TB, tracheal stenosis should be considered.
How Is Tracheal Stenosis Diagnosed?
Diagnosis follows a clear sequence from less invasive to more definitive.
Spirometry with flow-volume loop
A standard breathing test can provide an early, non-invasive clue. In tracheal stenosis, the flow-volume loop shows a characteristic flattening of the inspiratory curve, indicating a fixed upper airway obstruction. This is different from the flow-volume loop seen in asthma. It does not confirm the diagnosis on its own, but it directs the clinician toward further investigation.
CT scan of the neck and chest
Cross-sectional imaging maps the location, length, and character of the narrowing. It also shows whether there is external compression from a mass or lymph node. CT is essential for planning treatment, because the length of the stenotic segment determines which intervention is appropriate.
Bronchoscopy: direct visualisation and grading
Direct visualisation through a bronchoscope is the gold standard for diagnosing tracheal stenosis. The doctor can see the narrowing, assess the tracheal lining, and measure the degree of obstruction. Two grading systems are used: the Cotton-Myer system (Grade I to Grade IV based on percentage narrowing) and the McCaffrey classification, which considers lesion length and location for predicting outcome. Grading guides the choice of treatment and helps predict response.
What Happens If Tracheal Stenosis Is Not Treated?
Tracheal stenosis tends to progress if left alone. Scar tissue can continue to contract and thicken, reducing the airway opening further over time. A patient who is breathless only on exertion today may become breathless at rest within months.
At Grade III or Grade IV stenosis, when more than 70 percent of the lumen is obstructed, there is a real risk of acute respiratory failure. A respiratory infection, increased secretions, or physical exertion can tip a severely narrowed airway into a crisis. This is a medical emergency.
Early diagnosis and treatment offer a much better outcome than waiting until symptoms become severe. The narrower the airway at the time of treatment, the more technically demanding the intervention becomes.
How Is Tracheal Stenosis Treated?
Treatment depends on the cause, location, length, and severity of the stenosis. Short, simple stenoses can often be managed bronchoscopically, without open surgery. Options include balloon dilation to widen the narrowed segment, laser resection or argon plasma coagulation to remove scar tissue, and placement of an airway stent to hold the airway open.
Longer or more complex stenoses may need surgical tracheal resection and anastomosis, where the narrowed segment is removed and the two ends of the trachea are rejoined.
For a full explanation of each option, candidacy criteria, and what to expect, see the dedicated tracheal stenosis treatment page.
Frequently Asked Questions
What is the most common cause of tracheal stenosis?
Post-intubation stenosis is the most common cause. It develops when scar tissue forms at the site where an endotracheal tube cuff pressed against the tracheal wall during ventilation. Symptoms typically appear six weeks to three months after the patient leaves the ICU. In India, post-COVID ICU admissions significantly increased the number of patients presenting with this condition.
Can asthma be mistaken for tracheal stenosis?
Yes, and this is a recognised clinical problem. Both conditions cause breathlessness and an abnormal breathing sound. The key difference is that asthma produces wheeze mainly on exhalation, while tracheal stenosis produces stridor mainly on inhalation. More practically: if your breathlessness has not improved with inhaler therapy and you have a history of intubation or TB, tracheal stenosis should be considered.
How is tracheal stenosis diagnosed?
Diagnosis typically follows three steps. A spirometry flow-volume loop may show a characteristic pattern of fixed upper airway obstruction. A CT scan of the neck and chest maps the location and length of the narrowing. A bronchoscopy then provides direct visualisation and grading of the stenosis, using the Cotton-Myer or McCaffrey classification.
Is tracheal stenosis a serious condition?
It can be, particularly if left untreated. At mild to moderate grades, patients manage daily activities with reduced tolerance. At severe grades (Cotton-Myer Grade III or IV, meaning more than 70 percent of the lumen is blocked), there is a risk of acute airway crisis. Early diagnosis and treatment significantly improve the outlook.
How long after intubation does tracheal stenosis develop?
Most patients develop symptoms between six weeks and three months after extubation. Some cases are identified earlier; in a small number of patients, symptoms appear later. The absence of symptoms immediately after leaving the ICU does not rule out stenosis. Any patient with persistent exertional breathlessness after ICU care should be evaluated.
Can tracheal stenosis be treated without surgery?
Many cases, particularly short-segment stenoses, can be managed bronchoscopically without open surgery. Balloon dilation, laser treatment, and stent placement are all performed through a bronchoscope under sedation or anaesthesia. Longer or recurrent stenoses may require surgical resection. The most appropriate approach depends on the individual case, which is why specialist assessment matters.
Talk to an Interventional Pulmonologist
If your breathing has not improved with inhalers, if you have a history of ICU admission or TB, or if a recent spirometry or CT scan has flagged abnormal airway narrowing, the right next step is an assessment by an interventional pulmonologist.
Dr. Kunal Waghray, MD DM DNB MNAMS EDRM, sees patients at Respire Airway Clinics in Basheer Bagh and Jubilee Hills, Hyderabad. He trained at Amrita Institute of Medical Sciences, Kochi, and performs the full range of bronchoscopic airway interventions. Consultations are available for new patients and for referrals from chest physicians and intensivists.
Clinical References
- Post-intubation tracheal stenosis in COVID-19 patients: Indian case series. Indian J Surg. 2022. PMCID: PMC9261125.
- Tracheal Stenosis: Experience at a Tertiary Care Centre in India. Indian J Otolaryngol Head Neck Surg. 2013. PMCID: PMC3938713.