Breathing is the most critical function your body carries out. Without the exchange of oxygen and other gases in the lungs, other vital organs like the brain and heart don’t get the energy they need to function. If they lose oxygen, these organs can start to die off in just minutes.
While there are a number of newer technologies like X-rays and computed tomography (CT) scans to help diagnose problems that can affect your lungs, auscultation — or listening to you lungs with a stethoscope — is one of the best diagnostic methods.
Normal lung sounds are clear and equal across the five sections of your lungs:
- right upper lobe
- right middle lobe
- right lower lobe
- left upper lobe
- left lower lobe
When other sounds are added or when normal breath sounds are missing, these can all indicate problems. Abnormal breathing sounds are sometimes called adventitious lung sounds. These are any additional or unexpected sounds that are heard with a stethoscope as you breathe in and out.
Types of abnormal breath sounds include:
- Rales. This is a fine, high-pitched crackling or rattling sound that can occur when you inhale.
- Rhonchi. This is a low-pitched sound that resembles snoring.
- Wheezing. This is a high-pitched sound, almost like a long squeak, that can occur as you inhale or exhale.
- Stridor. This is a high-pitched, loud sound that sometimes sounds like a cough or bark.
Each of these types of sounds can signal different problems in the airway and lead your doctor or nurse in the direction of a particular diagnosis and treatment.
In the rest of this article, you’ll learn about rales and rhonchi, what causes these sounds, and what treatment you can expect.
Rales and rhonchi can both be coarse, even crackling sounds. The difference between the two is in the pitch and the exact cause of the sound.
Rhonchi
This low-pitched sound that usually starts in the larger airways in the lungs. It can be heard on an inhale or exhale, and it’s often compared to the sound of snoring. Rhonchi can either come and go on and inhale or exhale or be heard continuously.
These sounds are produced when there is something blocking the airway, like fluid. The sound you hear is the the sound the air makes as it moves around the blockage.
Listen to rhonchi here on the Medzcool YouTube channel.
Rales
Rales are a higher-pitched sound sometimes called crackles or bibasilar crackles. The terms rales or crackles have been used interchangeably and are usually a matter of preference, not a difference in the condition.
These sounds are formed when air moves into closed spaces. This usually occurs in the smaller parts of the lungs, like the alveoli. These are tiny sacs of air and inflate and deflate with each breath. When these tiny sacs are damaged or weighed down with fluid or mucus, they can make a crackling sound as they attempt to fill with air.
Rales are usually broken up into more specific types, based on the way they sound. Types of rales include:
Listen to rales here on the Medzcool YouTube channel.
It can be difficult to differentiate abnormal lung sounds from one another — and it can be just as tricky to find out what is causing these sounds. While both sounds can be caused by infections and fluid buildup in the lungs, there are a few conditions that are more unique to each sound.
Conditions that can cause both rhonchi and rales include:
Conditions more common to rales include:
- pulmonary edema
- interstitial lung disease
- asthma
- heart failure
Conditions more common to rhonchi include:
- cystic fibrosis
- chronic obstructive pulmonary disease (COPD)
- bronchiectasis
Once a healthcare professional detects these sounds, they’ll investigate the cause further. You may undergo imaging studies including:
If these abnormal lungs are detected, a healthcare professional will try to determine the exact cause. Treatments will focus on relieving underlying chronic causes or clearing up short-term or acute infections.
For example. if heart failure is the cause fluid buildup in your lungs, the treatment would be different than if fluid buildup were from a condition like COPD.
Some examples of medications you may be instructed to take to either clear or open your airways include:
- inhaled steroids to reduce inflammation
- bronchodilators to relax and open airways
- mucolytics or other medications to reduce mucus production and relieve congestion
- antibiotics if the buildup is caused by an infection
- antiviral medications if the problem is caused by a respiratory virus like influenza
- oxygen therapy if the problem causes a drop in your body’s oxygen level
- pulmonary rehabilitation or respiratory therapy to help you learn how to clear and strengthen your lungs
Chances are, you won’t hear these lung sounds on your own, but you may have a number of symptoms that can lead to you see a healthcare professional. If you have a cough that isn’t going away or shortness of breath, you should make an appointment to see a clinician.
If you experience severe shortness of breath, chest pain, loss of consciousness, or a bluish tinge to your lips or fingernails, you should seek immediate medical care.
Breath sounds can provide a lot of information about the health of your lungs. Certain sounds are created by specific conditions. If you notice any unusual sounds when you breathe in and out or have ongoing respiratory problems, be sure to see a medical professional.
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