Air trapping in emphysema occurs when the lung’s tiny air sacs become stretched and the airways narrow, making it difficult to catch your breath. Medications can help open up the airways and improve breathing.
Air trapping is one of the serious complications of emphysema, a respiratory condition that, along with bronchitis, is part of chronic obstructive pulmonary disease (COPD). Air trapping refers to the air that remains in the lungs when trying to exhale. The result is constantly feeling short of breath.
The severity of air trapping can often help predict a person’s outlook with emphysema. However, treatments, including oral and inhaled medications as well as certain breathing techniques, may help relieve symptoms and improve outcomes.
Air trapping is a common feature of emphysema and occurs when, during exhalation, the lungs don’t empty normally. More air is retained in the lungs than should be. With each subsequent full inhalation, more and more air can remain in the lungs, leading to hyperinflation of the lungs and causing shortness of breath.
The lung contains a network of air tubes that bring oxygen into the lungs called the bronchioles. At the end of the bronchioles are the alveoli, little clusters of air sacs in which oxygen is transferred into the bloodstream and carbon dioxide is removed from the blood to be exhaled from the body.
Air trapping occurs within alveoli that have become stretched and are unable to take in and remove air effectively. Air trapping is compounded by narrowed bronchioles, which are narrowed airways. The combination of non-stretchy alveoli and narrowed airways prevents the lungs from emptying fully, causing the air to become trapped.
Air trapping’s main symptoms include shortness of breath and wheezing.
Other symptoms can include:
- chest tightness
- coughing, typically producing a lot of mucus
- whistling sound when breathing
The American Thoracic Society notes that smoking is the main cause of emphysema and air trapping. Prolonged exposure to secondhand smoke and airborne pollutants may also lead to emphysema.
The primary tool used to diagnose air trapping is body plethysmography, a type of full lung function test performed by a respiratory care technician who also monitors you throughout the test.
Other tests that may be used to diagnose air trapping include:
- Chest X-ray: Chest X-rays may help confirm emphysema while ruling out other potential causes of your symptoms.
- CT scan: One of the main imaging tools, a CT scan creates cross-sectional images of the lungs to reveal the health and function of the alveoli and other features of the lungs.
- Forced spirometry: Though less accurate than body plethysmography, air trapping may be assessed using forced spirometry, a lung function test that measures how much you can exhale with a forced breath.
A history of tobacco smoking is the main risk factor for emphysema and certain other respiratory conditions, including lung cancer. Emphysema that isn’t treated effectively with medications and lifestyle changes is a key risk factor for air trapping.
There’s also a hereditary element to emphysema and air trapping. A genetic condition called alpha-1 antitrypsin deficiency can lead to emphysema, as can a family history of COPD.
Medications called bronchodilators are the main treatments for air trapping. Bronchodilators help the airways relax. They’re usually taken with inhalers, but some bronchodilators are taken as oral tablets or as syrups.
A 2021 study suggests that bronchodilators reduce air trapping and expand airway openings in the lungs. That same study also notes that pursed-lip breathing can ease the shortness of breath symptoms associated with air trapping.
In more serious cases of emphysema, oxygen therapy may be necessary to help keep a consistent flow of oxygen to the lungs and the rest of the body.
For people with emphysema, air trapping is just one complication used to predict the course of the disease. A 2022 study suggests that the severity of air trapping is helpful in forecasting the exacerbations of COPD, especially in individuals who haven’t undergone triple inhaler therapy.
Emphysema is usually categorized by stage, with the severity of each stage determining the outlook for a person with the condition.
The main ways to prevent air trapping are the same as those to prevent emphysema and other respiratory conditions. These strategies include:
- not smoking or quitting smoking if you currently smoke
- limiting your exposure to secondhand smoke
- avoiding or limiting your exposure to airborne pollutants
Is there a cure for emphysema?
There’s currently no cure for this condition that affects about 3 million people in the United States. However, there are a variety of treatments that may help ease symptoms.
Does emphysema affect both lungs?
Emphysema can affect one or both lungs, though both lungs are usually affected as the disease progresses.
Does air trapping ever require surgery?
In severe cases, when air sacs have been destroyed, surgery to remove bullae may be necessary to help restore efficient breathing.
Emphysema air trapping is a condition that makes it difficult to exhale completely. You can feel like you never quite catch your breath.
Never smoking or quitting smoking as soon as possible are the best ways to prevent emphysema air trapping from developing. But if it does develop, there are medications that may help you breathe easier.