Supplemental breath sounds are abnormal lung sounds heard in the chest, usually with a stethoscope. They can provide clues to help diagnose lung (lung-related) or heart disease . Some associated breath sounds can be heard without the aid of a stethoscope. These sounds can be described as wheezing, crackles (also called wheezing), wheezing (sometimes called wheezing), pleural friction, and stridor.
Extra breath sounds can often be the first sign of illness in a variety of conditions, including an infection (for example, pneumonia , an infection that inflames the air sacs in one or both lungs), interstitial lung disease (a group of diseases that scar tissue in the lungs), pulmonary edema (excess fluid in the lungs), or chronic obstructive pulmonary disease (COPD).
Auscultation is the process of listening to the sounds of the lungs , heart, or other organs with a stethoscope. Lung auscultation, also known as chest auscultation, is usually performed by a doctor who can diagnose or rule out conditions based on sounds that are coming from specific areas of the lungs.
Lung sounds can be heard in all areas of the chest, including above the collarbones and lower chest. The health care professional performing the auscultation may hear normal breath sounds, muffled or absent breath sounds, or occasional breath sounds.
The exam is best done in a quiet place and may require exposure of the chest and back. The examinee generally sits in a chair or on the edge of the bed for auscultation. Breath sounds will vary depending on where the air is passing through the lungs.
Types of breath sounds
There are several types of breath sounds, including :
- Tracheal sounds: These sounds are heard over the windpipe. They are sharp and loud.
- Bronchial sounds: These sounds are high-pitched and muffled. They pass through the front of the chest through the bronchioles, which extend from the windpipe.
- Vesicular sounds: these silent sounds. They come from parts of the lungs that are involved in gas exchange.
- Bronchovesicular sounds: these average tonnage the sounds emanate from the back of the chest.
Associated types of breath sounds
Additional breath sounds usually indicate an underlying medical condition. They can be characterized as continuous (heard with every inhale and exhale) or intermittent (heard infrequently or when inhaling or exhaling). Sounds can also vary in pitch. The characteristics of breath sounds can help the doctor distinguish between different sounds to narrow down the possible causes of these sounds.
Wheezing is a continuous, high-pitched whistle. It is caused by fluttering air movements due to constriction or partial blockage of pus or fluid accumulated in the smaller airways (such as the bronchioles ). Whistling can sometimes be heard without a stethoscope .
Rhonchi is a term sometimes used synonymously with wheezing, but the sound is harsher, lower, and louder than wheezing. The sound is similar to snoring. Like wheezing, wheezing is caused by fluttering air movements but through larger airways (such as the bronchi) .
Wheezing / wheezing
Wheezing, also known as wheezing , occurs when inhaling and is irregular. The crackling sound is usually high-pitched with a popping or hissing sound. It may also sound like crumpled cellophane. Wheezing may be less if the larger airways are affected. These sounds can also be described as wet, dry, shallow (high), or harsh (low). They occur because the smaller airways (and sometimes the larger airways) open up when you breathe in. …
Also called a pleural friction murmur, a pleural friction murmur is a continuous, low, harsh, harsh sound. It sounds similar to wheezing, but it comes from a specific area of the chest or lungs, unlike the more common squeaks. Pleural friction is caused by the friction of the inflamed pleural membranes during the movement of the chest wall during inhalation and exhalation .
This sound is caused by the narrowing of the airways. It can be heard when inhaling and intermittently (on and off). Stridor is loud and noisy with wheezing from the upper respiratory tract, especially around the larynx and pharynx . It is more common in children because their airways are softer and narrower .
|Reasons for the appearance of random sounds.|
|Kind of||Sound||Possible reasons|
|Wheezing / wheezing||Musical, high||Asthma, croup, COPD, foreign body|
|Wheezing / wheezing||Deep, rough||Heart failure, pneumonia, chronic bronchitis|
|Pleural friction murmur||Not musical, squeaky, squeaky||Inflammation of the lung membrane, lung tumor.|
|Stridor (adults)||Variable, high||Epiglottitis, foreign body, laryngeal edema|
|Stridor (children)||Variable, high||Croup, foreign body|
Snoring, screaming (a shortened hissing sound that can occur with pneumonia), and whooping cough (associated with whooping cough ) are also considered associated breath sounds .
Various tests, including blood tests, imaging, and lung function tests , may be performed to assess how well the lungs are working and the possible causes of the associated breath sounds.
A blood culture can be used to look for bacteria in the bloodstream. Blood tests that your doctor may order to evaluate occasional breath sounds include:
- Arterial blood gas (AG): evaluates the levels of oxygen and carbon dioxide in the blood. It tests how well the lungs can carry oxygen into the blood and remove carbon dioxide from the blood.
- Complete blood count (CBC): measures many different parts and characteristics of the blood, including red blood cells and hemoglobin, which carry oxygen from the lungs to the rest of the body. Detects infections, anemia and diseases of the immune system.
- Natriuretic Peptide (NT-proBNP) Test: Performed only if heart failure is suspected. It measures the levels of brain natriuretic peptide and pro-b-type N-terminal natriuretic peptide in the bloodstream. A high level can mean that the heart is not pumping as much blood as the body needs.
Generally, several types of imaging are used to diagnose conditions such as acute pulmonary embolism, advanced COPD, and pneumonia.
Imaging tests that are commonly prescribed to assess lung function include:
- Chest X -ray – Allows the doctor to examine the structure of your lungs and the condition of your chest cavity.
- CT – Provides more detailed images of the lungs than a chest X-ray.
- Echocardiogram – Uses sound waves to create images of the heart's chambers, valves, walls, and blood vessels (aorta, arteries, veins) attached to the heart.
Pulmonary function tests.
Pulmonary function tests are a group of non-invasive tests (which do not require insertion of instruments into the body) that assess the quality of a person's breathing and how well their lungs are working when abnormal lung sounds are heard.
Various lung function tests include:
- Spirometry – measures how much air you breathe out and how fast you breathe out.
- Stress test: assesses the state of the lungs and heart in conditions of increased metabolic demand (during exercise).
- Pulse oximetry: measures the oxygen carried by blood cells.
- Sputum culture: looks for bacteria or other microorganisms that can cause infection in the lungs or the airways leading to the lungs.
The doctor may start with a lung function test, which measures the flow of air in the lungs and how well they are working. Your healthcare provider will discuss the following spirometry measures with you:
- Forced Vital Capacity (FVC): The amount of air that a person can forcefully exhale from the lungs after inhaling as deeply as possible.
- Total Lung Capacity (TLC): the total volume of air in the lungs after maximum inspiration.
- Forced Expiratory Volume (FEV): The amount of air that a person can exhale during forced breathing.
- Forced expiratory flow rate 25% to 75% (FEF25-75): mean forced expiratory flow. the rate exceeds the average 50% FVC, which is the total amount of air exhaled during the FEV test.
Normal values will depend on your age, gender, height, and ethnicity. Generally, a reading below 80% of its predicted value is considered abnormal.
If the results show impaired lung function, your healthcare provider may have enough information to diagnose a condition such as asthma or COPD. If more information is required, additional tests such as CT scan or blood tests may be ordered.
When to call your healthcare provider
By themselves, the associated breath sounds do not indicate a specific diagnosis and do not provide a clue to understanding the severity of the condition. If you experience shortness of breath, especially if it persists, call your doctor. Call 911 if abnormal breath sounds develop rapidly and occur if :
- Severe shortness of breath
- Dizziness or fainting
- Fast or irregular heartbeat
- Expansion of the nose
- Cyanosis (blue skin)