As part of a comprehensive lung exam, a doctor may try to listen for various sounds by tapping your back and chest with their hand, which is a test called percussion.
If the percussion produces a drum-like sound known as hyperresonance, it could indicate air has filled the space around your lungs and is prohibiting them from expanding fully. It may also suggest that air is trapped inside the small airways and alveoli (air sacs) of your lungs.
Hyperresonance can be a sign of chronic obstructive pulmonary disease (COPD) or another respiratory condition. It may also indicate that the condition is worsening and that more aggressive treatment may be necessary.
Although percussion is no longer used to help diagnose COPD, there is older research that suggests it should be.
The sounds your lungs make can help a doctor diagnose COPD, asthma, or other pulmonary conditions. They can also help a doctor determine whether your respiratory health is strong.
You may be more familiar with auscultation, which involves listening to your lungs with a stethoscope. Doctors perform auscultation while you inhale and exhale. The sounds your lungs make can indicate narrowed airways, for example.
But chest percussion aims to determine if there’s too much air or fluid in lung tissue. There are three distinct sounds a physician listens for, and each one suggests a different diagnosis:
- A resonant or fairly low, hollow noise is often a sign of healthy lungs.
- A dull or flat sound suggests fluid in your lungs (pneumonia) or in the space between your lungs and chest wall (pleural effusion). It can also be a sign of a lung tumor.
- Hyperresonance suggests too much air around your lungs or in the lung tissue itself.
Hyperresonance is often a symptom of a type of COPD called emphysema. In emphysema, tiny air sacs in your lungs become damaged and enlarged.
This can lead to hyperinflation, which means there’s an atypical amount of air in your lungs. Hyperinflation, in turn, expands your rib cage, creating a temporary condition known as “barrel chest.”
If COPD or another respiratory problem is suspected, a doctor may perform chest percussion to help reach a diagnosis. If you’ve already received a diagnosis of COPD, chest percussion is one way a doctor can determine how much, if at all, your condition is progressing.
Doctors may do chest percussion a few different ways. Generally, the test starts with a doctor placing a hand flat on your chest or back. They’ll then use their other hand’s index or middle finger to tap the middle finger of the hand that is against your skin.
The doctor may start on your chest or back. But a comprehensive exam should involve tapping or percussing several locations around your torso to understand how both lungs sound, top to bottom.
There are other diagnostic tests for COPD, including a breathing test called spirometry. But in a
Can hyperresonance indicate a condition other than COPD?
While hyperresonance is a common symptom of COPD, it can also indicate another serious respiratory condition known as pneumothorax.
The space between the lungs and chest wall is usually hollow. In the case of pneumothorax, also known as a collapsed lung, air fills that space and puts pressure on one or both lungs.
A person having an asthma attack may also produce hyperresonance with chest percussion. Their lungs become hyperinflated as exhaling becomes more difficult.
Can I perform a chest percussion exam on my own to test for COPD?
Someone may teach you self-percussion but not necessarily as a diagnostic tool.
People with chronic bronchitis, another form of COPD, may use chest percussion to clear mucus from their lungs, but that is a different process.
Are there any other obvious signs of COPD?
Other telltale signs of COPD include:
- chest tightness
- chronic cough that may produce mucus
- shortness of breath
- repeated respiratory infections
- wheezing or whistling when exhaling (sometimes also when inhaling)
Sounds of COPD
Along with other symptoms, such as a chronic cough, certain COPD lung sounds can help healthcare professionals get a sense of whether you might have COPD or how the disease is progressing.
Some of the key sounds of COPD include:
- crackling (or clicking) when inhaling
- rhonchi, a low-pitched wheezing sound
- whooping or a high-pitched gasping for air
Hyperresonance can be a significant indicator of COPD. Chest percussion is an advisable test to undergo if a doctor suspects COPD.
A joint 2015 statement by the American Thoracic Society and European Respiratory Society indicates that the combination of hyperresonance and decreased breath sounds likely suggests that someone has COPD.
COPD is a serious respiratory ailment. But if you receive an early diagnosis and stick to your treatment plan, it can be a manageable condition. Learning self-percussion may help clear your lungs of mucus.