Tracheobronchomalacia (airway collapse): symptoms, diagnosis and management

The windpipe and the large airways that branch off it are held open by rings of cartilage. The Cambridge University Hospitals leaflet explains that in tracheobronchomalacia the cartilage in the airway walls softens, so the airways are floppy. When the muscles relax to let you breathe out, the airways cannot stay fully open and partly close, which makes it harder for air to leave the lungs. If you have phlegm, it also gets stuck when the airways partially close as you breathe out, making it more difficult to clear.

A published review of expiratory central airway collapse explains that two processes are involved. Excessive dynamic airway collapse (EDAC) is excessive inward bulging of the posterior membrane, the soft back wall of the windpipe, while malacia refers to collapse of the cartilage. Depending on the site, the latter is called tracheomalacia, bronchomalacia or tracheobronchomalacia. The review notes that EDAC is sometimes considered just a symptom of obstructive lung disease, and that this is debated.

The Cambridge leaflet says TBM can be due to genetic links and is often first found in children. In adults, it is thought either to be a consequence of another condition or problem or to have no known cause. Long-term irritation and coughing occurring with asthma and chronic obstructive pulmonary disease (COPD) may weaken the airway walls, causing airway collapse.

The published review lists secondary causes as airway trauma, medical procedures such as tracheostomy, chronic recurrent airway infections, chronic external compression of the central airways by, for example, enlarged lymph nodes, autoimmune inflammation, or mechanical factors such as after lung surgery. This means that in an adult the condition is often found alongside another chest problem, and a specialist will look for a contributing cause.

According to the Cambridge leaflet, symptoms include a cough that often sounds like a bark, shortness of breath, wheezing, difficulty clearing secretions, recurrent chest infections and feeling less able to do physical exercise.

Chest infections are a particular concern. The leaflet says TBM means you are at greater risk of chest infections and that the more infections you have, the more likely it is that there will be damage to the lungs, so controlling the number of infections is a key part of staying well. It lists signs of an infection that are different from your normal: increased amounts of sputum, thicker sputum that is harder to clear, darker coloured sputum, a high temperature, chest discomfort and coughing up small amounts or streaks of blood.

Seek prompt medical advice, from your GP or NHS 111, if you have signs of a chest infection. If you are severely breathless or struggling to breathe, call 999.

Because the symptoms resemble asthma and COPD, diagnosis is often delayed. The published review describes patients whose symptoms did not respond to bronchodilators and inhaled corticosteroids, and in whom the collapse was seen during bronchoscopy, a camera examination of the airways, and on a CT scan taken while breathing out. Spirometry, the breathing test, may show only mild or no obstruction that does not match how breathless the person feels.

Diagnosis therefore rests on a respiratory specialist's assessment and tests that look at the airways during breathing out, such as the expiratory CT scan and bronchoscopy described in that review. Your team will also look for associated problems such as asthma, COPD, bronchiectasis or reflux, which can all contribute to symptoms.

The Cambridge leaflet says the problems with the airways cannot be reversed, so treatment is aimed at reducing symptoms, managing mucus and preventing further damage. It says inhalers are not effective for TBM because airway wall weakness does not respond to medication that opens the airways or reduces inflammation, although people with another respiratory condition may already be using them. Treatments to hydrate or thin mucus, such as saline nebulisers or carbocisteine capsules, may be used. On some occasions people are referred for consideration of home ventilation, and occasionally operations may be helpful, but this is rarely needed.

Respiratory physiotherapy is central. The leaflet says a respiratory physiotherapist will assess you and create a personalised plan to perform at home. Techniques may include breathing exercises such as the active cycle of breathing technique, without forced expiratory technique, because forcing the breath out can lead to airway collapse, devices such as Acapella or Aerobika, and positioning to target the most affected parts of the lungs, known as postural drainage. It advises doing these daily, even when well, and increasing them during an infection.

The leaflet notes that an infection is often treated with at least a one-week course of oral antibiotics, that severe infections may need intravenous antibiotics and hospital admission, and that some people who get many infections may be advised to take continuous antibiotics. It suggests giving a sputum sample to your GP or practice nurse before starting antibiotics so the right antibiotic can be chosen.

The published review describes two patients whose symptoms improved after treatment with N-acetylcysteine and an adjustable positive expiratory pressure valve, together with cough techniques and, in one, reflux treatment. This is a small case report, and it should be read as an illustration of what specialists may try, not as a guaranteed response.

The Cambridge leaflet lists general measures that matter more in TBM: stop smoking, because smoking damages the airways and increases sputum; stay active, with 150 minutes of moderate activity a week for adults aged 19 to 64 where possible; eat a balanced diet; keep a healthy weight; stay hydrated so mucus does not thicken; and have recommended vaccinations such as flu, pneumonia, COVID and RSV vaccines. It suggests speaking to your GP about these. A physiotherapist can advise on starting exercise safely.

Many people find it helpful to agree an action plan with their respiratory team so that they know when to start extra airway clearance and when to contact the GP or hospital. Keep a note of what your usual sputum looks like so that changes are easier to recognise.

On the NHS, care is usually led by a respiratory consultant with support from respiratory physiotherapists and specialist nurses. The Cambridge leaflet says operations are rarely needed. Private respiratory consultants can offer earlier review and imaging, and physiotherapy may also be available privately. Whichever route you choose, ask for a written plan for airway clearance and for infections, and make sure your GP is kept informed.