Definition: These sounds come from the lungs when you breathe, inhale and exhale.
These sounds can be heard using a stethoscope or simply when breathing. Respiratory sounds may be normal or abnormal.
Although many newer imaging techniques have been developed for the evaluation of pulmonary pathologies, chest auscultation remains an invaluable clinical tool and is still probably the most common method of evaluating the lungs.
The evaluation of lung sounds is a routine part of a clinical examination.
Respiratory sounds can be classified into 2 broad categories: normal breathing sounds and adventitious (or abnormal) sounds.
The adventitious sounds of breathing include wheezing, coarse crackle, crackling, and hoarseness.
Abnormal sounds of breathing can indicate a lung problem, such as:
- An obstruction
- An infection.
- Liquid in the lungs.
Types of respiratory sounds
Your doctor will use a medical instrument called a stethoscope to listen for normal breathing sounds.
A normal sound of breathing is similar to the sound of air. Your doctor can hear normal breathing sounds by placing the stethoscope on your:
- Rib cage.
Your doctor may also use a stethoscope to hear abnormal breath sounds, which may include:
- Grunts, which are low-pitched sounds.
- Crepitans, which are sharp sounds.
- Wheezing, which is an acute whistling caused by narrowing of the bronchial tubes.
- Stridor, which is a loud, vibrating sound caused by the narrowing of the trachea
What are the causes?
Abnormal breath sounds are usually indicators of problems in the lungs or airways. The most common causes of abnormal breath sounds are:
- Heart failure.
- Chronic obstructive pulmonary disease, such as emphysema.
- A foreign body in the lungs or airways.
If the small air sacs in the lungs become filled with fluid, any movement of air in the sacs, such as when you are breathing, causes crackles.
Air sacs fill with fluid when a person has pneumonia or heart failure. Snoring occurs when air tries to pass through bronchial tubes that contain fluid or mucus.
Wheezing occurs when the bronchi become inflamed and narrow. Stridor occurs when the trachea narrows.
Evaluation of breathing sounds
If possible, auscultation of the thorax should be done with the patient in a sitting position. The diaphragm of the stethoscope should be used. The examiner should warm the stethoscope between his palms before placing it on the patient’s chest.
The stethoscope should be placed against the patient’s bare skin; The examiner should not try to listen through the patient’s clothing.
The examination should include listening to the anterior part of the thorax, the middle region and the posterior thorax. The posterior thorax should be examined up to the base of the thorax.
Respiratory sounds should be evaluated during quiet and deep breathing. A full breath should be listened to in each place. The examiner should listen to the tone, intensity, duration and distribution of respiratory sounds, as well as note any abnormal or adventitious sound.
When respiratory sounds are considered a medical emergency?
If the breathing difficulty appears suddenly, it is serious or if someone stops breathing.
Cyanosis, a bluish color of the skin and mucous membranes due to lack of oxygen, can occur along with abnormal breath sounds.
Cyanosis that involves the lips or face is also a medical emergency. Your doctor will also look for the following signs of an emergency:
- The nasal flare, which is an enlargement of the opening of the nostrils during breathing that can be a sign that breathing is difficult and is usually seen in infants and young children.
- Abdominal breathing, which is the use of abdominal muscles to help breathing.
- The use of accessory muscles, which is the use of the neck and muscles of the chest wall to help breathing.
- Stridor, which indicates an obstruction of the upper airway.
Discovering the cause
Your doctor will check your medical history to determine what is causing the abnormal breath sounds. This includes any current or past medical condition and any medication that you are taking.
Tell your doctor when you notice abnormal sounds when you breathe and what you were doing before you heard them. Be sure to mention any other symptoms you are experiencing.
The doctor will then administer one or more tests to determine what is causing the abnormal sound. These tests include:
- A computerized tomography.
- A chest x-ray.
- Blood test.
- A pulmonary function test.
- A culture of sputum.
Your doctor may use a pulmonary function test to measure:
- How quickly you inhale and exhale.
- How much air it takes
- How much air exhales.
A sputum culture is a test to detect foreign organisms in the mucus of the lungs, such as abnormal bacteria or fungi.
For this test, your doctor will ask you to cough up and collect the sputum you coughed. This sample is sent to a laboratory for analysis.
Treatment options for abnormal breath sounds
There are treatment options available. The treatment options that work best for you depend on your diagnosis.
Your doctor will consider the cause and severity of your symptoms when recommending a treatment.
Medications are often prescribed to clear the infections or to open the airways. However, in severe cases such as fluid in the lungs or a blockage in the airways, hospitalization may be necessary.
If you have asthma, COPD or bronchitis, your doctor is likely to prescribe respiratory treatments to open the airways. People with asthma can receive an inhaler to use daily to prevent asthma attacks and inflammation of the airways.
To take into account
Call local emergency services or go to the nearest emergency room if someone:
- You have trouble breathing that occurs suddenly.
- You have severe breathing difficulty.
- You have cyanosis that involves the lips or face.
- Stop breathing.
Make an appointment with your doctor if you think you are having other symptoms of breathing problems, such as abnormal breathing sounds.
Having an open conversation with your doctor will help you identify any health conditions in the early stages.