The term ‘hyper inflated lungs’ describes the condition in which air gets trapped in the lungs, causing them to overinflate. This is typically as a result of certain pulmonary conditions, although mainly associated with chronic obstructive pulmonary disorder (COPD).
As hyper-inflated lungs is a secondary condition to COPD (or other pulmonary illness), it is important to address the primary condition first.
Hyperinflated lungs can cause difficulties with breathing, particularly during exercise, therefore it’s important to address the condition as soon as possible in order to avoid further damage to the lungs and further breathing difficulties.
Understanding hyper inflated lungs
What are the causes of hyper inflated lungs?
The cause of hyperinflated lungs is usually COPD. COPD is the name given to a collection of lung conditions that cause breathing difficulties, and is characterised by:
- Emphysema - damage to the air sacs in the lungs
- Chronic bronchitis - inflammation of the airways (long term)1
Some other lung problems can also cause lung hyperinflation. These include:
- Asthma
- Cystic fibrosis2
Causes of COPD
COPD is mainly caused by long-term exposure to harmful substances that enter the lungs, although it is most commonly associated with smoking.
- Smoking
90% of COPD cases are attributable to smoking. The chemicals in the smoke cause damage to the lining of the lungs and airways.
- Fumes and dust
Occupations with exposure to certain chemicals and types of dust have been linked to increased risk of COPD. These include:
- Cadmium dust and fumes
- Grain and flour dust
- Silica dust
- Welding fumes
- Isocyanates
- Coal dust
This is after repeated long term exposure and not after single events.
- Air pollution
Long term exposure to air pollution is thought to affect lung functioning. However, the link between air pollution and COPD is not conclusive.
- Genetics
There is also a genetic component which makes some individuals more susceptible to COPD. 1
What are the signs and symptoms?
As hyperinflation of the lungs is usually a result of COPD, below are the symptoms of COPD:
- Breathlessness: this increases when the individual is active, causing more shortness of breath
- A persistent chesty cough: this is a wet cough and can sometimes be mistaken for just a “smoker’s cough”
- Frequent chest infections
- Persistent wheezing1
The main symptom for lung hyperinflation itself is breathlessness.
What happens when you have hyper inflated lungs?
Hyperinflation of the lungs can be differentiated into two different types:
Static hyperinflation is caused by a loss of lung elasticity due to emphysema (damage to air sacs). The lungs expel less air when breathing out, resulting in a higher volume of air remaining in the lungs at rest between breaths. This extra remaining air is defined as trapped air.
Dynamic hyperinflation is much more common, occurring independently or dependently of static hyperinflation. This is caused by air becoming trapped in the lungs as more air is inhaled than exhaled. Less air can be exhaled due to airflow limitations and the time given to exhale. (3
What are the complications?
As the hyperinflation of lungs involves trapped air in the lungs causing shortness of breath, the main complications involved are:
- Exercise intolerance - shortness of breath increases with exercise
- Fatigue
- Difficulty inhaling
Chronic hyperinflation can have serious complications relating to heart functioning – the increased pressure in the chest cavity from the trapped air can affect the heart. Over time, the left ventricle can become weaker and unable to pump blood out of the heart efficiently. This can ultimately lead to heart failure.
How is it diagnosed?
Given that hyper inflated lungs are usually a symptom of COPD or other lung-related conditions, it is usually diagnosed as part of, or following the confirmation of, the lung condition. The physician will look at your medical history as well as conduct a physical exam. This exam will involve using a stethoscope to listen to the sounds of your breathing. A potential abnormal sound they may hear is a “barrel chest,” where the chest seems constantly inflated. Lung function tests may also be conducted. 4
The hyper inflated lungs are visualised using imaging techniques such as a chest X-ray or CT scan. A chest X-ray is more commonly used and this will show fluid and air surrounding the lungs, suggesting a problem with the respiratory system. Hyperinflation is confirmed if more than 6 front ribs are above the diaphragm.5
Treating hyper inflated lungs
Given that hyperinflated lungs are a consequence of COPD, treatment is primarily focused on COPD. As this condition is incurable, the treatment options concentrate on easing symptoms and preventing further loss of lung function.
With respect to treating the hyper inflated lungs themselves, there are surgical options to reduce the lung volume. They aren’t used as commonly as drugs and other less invasive treatment options, but are still used for reducing the trapped air in the lungs.
Lung volume reduction surgery
Lung volume reduction surgery is a treatment option for emphysema. This involves the most damaged part of the lungs being removed in order to allow the healthier parts of the lung to function better. The removal of these lung sections means that the most enlarged air sacs get removed, so less air is trapped in the lungs. This increases the efficiency of air flow and makes breathing easier.
Bronchoscopic lung volume reduction
Sometimes known as endobronchial valve replacement, this treatment option involves placing valves into the airways via a bronchoscope (a long and narrow flexible tube that goes down the nose allowing the airways to be seen). The valve placed will then block off the worst parts of the lung, allowing air to pass to the healthier tissue for better lung function.6
When to consult a doctor
You should speak to your doctor if you experience persistent COPD symptoms. This is particularly important if you’re aged over 35 and have a history of smoking1
Summary
Lung hyperinflation is most commonly a consequence of COPD, a chronic lung condition consisting of emphysema and chronic bronchitis. It involves air being trapped within the chest cavity, causing shortness of breath. If left untreated for long periods of time, it can have serious complications, ultimately resulting in heart failure. If you suspect you have COPD, seek medical advice from your doctor as soon as possible.
References
- Chronic obstructive pulmonary disease (COPD) [Internet]. NHS choices. NHS; 2019. Available from: https://www.nhs.uk/conditions/chronic-obstructive-pulmonary-disease-copd/
- Hyperinflated lungs: What does it mean? [Internet]. Mayo Clinic. Mayo Foundation for Medical Education and Research; 2017. Available from: https://www.mayoclinic.org/diseases-conditions/emphysema/expert-answers/hyperinflated-lungs/faq-20058169
- Ferguson GT. Why does the lung hyperinflate? Proceedings of the American Thoracic Society. 2006;3(2):176–9.
- Leader D. Hyperinflated lungs: Symptoms, causes, and treatment [Internet]. Verywell Health. Verywell Health; 2022. Available from: https://www.verywellhealth.com/hyperinflation-of-the-lungs-914784
- Bell D, Delgado J. Lung hyperinflation. Radiopaediaorg. 2017;
- Lung volume reduction procedures for emphysema - British Lung Foundation [Internet]. Asthma + Lung UK. 2022. Available from: https://www.blf.org.uk/support-for-you/copd/treatment/surgery