Long-term respiratory complications

Tracheomalacia

Most people with a history of TEF have some degree of tracheomalacia, and even a few people with isolated EA also have tracheomalacia. In mild cases, it only leads to a loud or vibratory “TEF cough.” In more severe cases, it can cause wheezing and trouble breathing and even blue spells in babies, and recurrent pneumonia in older people, where collapse of the trachea during cough impairs expulsion of lung mucous during respiratory infections. The trachea (like the rest of us), tends to get stiffer as we get older, so tracheomalacia tends to become less of a problem as people age. Clinically significant tracheomalacia may occur in up to ¾ of young children, 1/3 of older children, and about 10% of teenagers and adults. Aspiration causes inflammation and swelling of the inner lining of the trachea, further narrowing the trachea and making tracheomalacia worse.

Tracheomalacia is sometimes diagnosed with motion-picture X-rays (called fluoroscopy) or computerized tomography scans (ciné-CT scan) of the chest. Most often, tracheomalacia is diagnosed with a bronchoscopy – placing a telescope into the trachea, with the patient sedated or under general anesthesia. An advantage of bronchoscopy is that lung secretions can be sent to look for evidence of persistent lung infection, and/or for evidence of aspiration.

Many people with tracheomalacia benefit from chest physiotherapy (or assisted airway clearance) techniques, to help expel lung secretions, during infections. One particularly helpful technique for older children and adults is a Positive Expiratory Pressure (or PEP) mask, where the patient breathes into a mask or mouthpiece with a tight resistor at the end, building up pressure inside the trachea and helping prevent it from collapsing.

During respiratory infections, the lining of the trachea can swell, making the inside of the trachea even narrower. Some physicians recommend treatment with an inhaled steroid, called budesonide, given by wet nebulizer, to shrink the lining of the trachea in people with tracheomalacia, when they have a respiratory infection and increased wheezing.

In people with tracheomalacia, there is some evidence that a bit of tightening of the muscles in the walls of trachea (called bronchospasm) helps keep the trachea more rigid, and impedes it from collapsing. In people with asthma, bronchodilator puffers (such as salbutamol) are used to relax muscles in the bronchi, as bronchospasm in people with asthma abnormally constrict the bronchi and make breathing difficult. Since people with tracheomalacia often wheeze, they’re often prescribed bronchodilator inhalers. It’s important to know that in people with tracheomalacia, these inhalers sometimes make the trachea less rigid and therefore make the wheezing worse, rather than better.

In severe cases, surgery called an aortopexy or innominate artery suspension is used, to move big, heavy blood vessels (such as the aorta) away from the trachea, so it collapses less during breathing and coughing. Up to a quarter of EA patients may need this surgery. In the most severe cases, infants may need a breathing machine and tracheostomy tube to help keep the trachea open.

Reccurent tracheoesophageal fistula

Weakness of the structures around the original TEF site can lead to a breakdown of these tissues, and a recurrent TEF. This happens in about 9% of EA patients – most often within the first 2-18 months after the original surgery. Symptoms include a recurrence of cough, choking, or blue spells with feeds – especially when drinking, and/or recurrent pneumonia.

Diagnosing a recurrent TEF can be tricky. They can be hard to see either during an upper endoscopy or a bronchoscopy. Sometimes, if both procedures are done at the same time, putting dye in the trachea can allow the visualized in the esophagus. The usual way a recurrent TEF is diagnosed is a “TEF study.” For this test, a catheter with a balloon is placed in the esophagus. The balloon is inflated, and a second catheter is placed in the esophagus, above the balloon. Barium is squirted in, under pressure, through the second catheter, and both catheters are slowly withdrawn while hydrosoluble contrast medium continues to be injected  to attempt to force it through a thready, little recurrent TEF (the same technique is usually used to diagnose an H-type TEF).

Recurrent TEF normally needs surgery. This can be done by opening the area or using endoscopy and re-repairing the TEF. Alternatively, some surgeons inject glue into the TEF. This is a smaller procedure, although it sometimes doesn’t completely fix the TEF.

Tracheal pouch

At the site of the original TEF, there’s usually a pouch (or pocket) that’s visible when a bronchoscopy is done. The pouch can be small, or quite large. Whether these pouches are important is controversial. Large ones can possibly fill up with mucous, possibly increasing the risk of pneumonia. There are reports that in EA patients with a tracheostomy, the end of the tracheostomy tube can get stuck in the pouch, blocking and leading to severe difficulties in breathing.

If these types of complications occur, the pouch can surgically or endoscopically be made smaller. In patients with respiratory symptoms, deciding that there isn’t a recurrent TEF deep inside a pouch can be challenging.

Reccurent bronchitis and pneumonia

Because of these various complications, including tracheomalacia, swallowing dysfunction and/or esophageal strictures and aspiration, and GERD and aspiration, people with EA are more prone to chronic coughs and respiratory infections than other people. This is more of a problem in children than adults, presumably because the airways are smaller and softer in children, esophageal function is worse, and the immune system is less developed. Nearly half of young children may get admitted for pneumonia. A recent large study of EA patients throughout Finland by Sistonen found that 16-30% of adult EA patients had chronic coughs, a quarter had at least 1 episode of bronchitis per year, and 10% were having pneumonias. Repeated respiratory problems and/or need for antibiotics should prompt your doctor to test for aspiration and/or tracheomalacia.

Very severe, persistent aspiration can cause permanent damage to the bronchi, where bronchi can get enlarged and permanently full of mucous. This is called bronchiectasis. While rare in EA patients, this is an important reason to make sure that chronic aspiration is not occurring. Bronchiectasis can be diagnosed by computerized tomography (CT) of the chest, and can sometimes be seen on a chest X-ray.

Asthma and wheezing

Roughly a quarter to a third of people with EA are diagnosed with asthma. Asthma is tricky to diagnose in EA patients, as both tracheomalacia and aspiration can cause narrowing of the bronchi and wheezing. These conditions should be ruled out before a diagnosis of asthma is made, as persistent aspiration can lead to lung damage. An important clue that wheezing in a EA patient isn’t due to asthma is that bronchodilator inhalers (such as salbutamol) rapidly improve wheezing in people with asthma, but have no effect in people with tracheomalacia – or make the wheezing worse. In people with EA, breathing tests can be performed in individuals 6 years of age and older, to evaluate these issues further.

Why EA patients may be more prone to asthma is an area of controversy. Some studies suggest that asthma in EA patients is linked to allergies, just like in other people with asthma. On the other hand, many experts believe that increased bronchial inflammation early in life, due to repeated aspiration, increases the risk of persistently inflamed airways later in life, resulting in asthma.

Given the many issues that can harm the lungs early in life in EA patients, many studies have looked at lung function in older EA children and adults. On average, lung function is normal, but towards the lower end of the normal range. About 1/3 of EA patients have completely normal lung function. About a third have narrower airways than the average, and about a third have somewhat smaller lungs than the average. Fortunately, exercise capacity is usually normal.

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Respiratory problems become steadily less frequent in adults (taken from Kovesi, Chest 2004)

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The number of people needing admission to hospital for respiratory or gastrointesinal causes falls markedly between childhood and adulthood

Tom Kovesi MD, Pediatric Respirologist, Children’s Hospital of Eastern Ontario, Ottawa, Ontario Canada
26/12/2016

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