Breath sounds

**Breath sounds** are the sounds made by air as it moves through the respiratory system. Breath sounds are also called **lung sounds** or **respiratory sounds.** Sometimes they can be heard by anyone; other times they can be heard only by listening to the lungs and airways with a stethoscope. 

In some life-threatening/chronic conditions (for example in serious asthma attacks), the lungs can be silent while breathing in or out, and this is called silent chest or silent lung syndrome.

To describe and identify breath sounds, medical professionals usually use auscultation (they listen with a stethoscope). They listen while the patient is breathing in, and while they are breathing out. They listen to both lungs, at both the chest and the back, starting at the bottom and working their way up. They listen to whether the pitch of the breath sounds is low, medium or high in all 2 or 3 lobes. They also listen to whether the sounds are soft, medium, loud, or very loud).

## Abnormal Breath Sounds
There are many kinds of breath sounds that are not normal. These are called adventitious breath sounds. Each different kind of abnormal breath sound is a sign of a different problem. Some of the most common abnormal breath sounds are:

Wheezing is caused by the airways being too narrow. This can happen because of diseases like asthma or chronic obstructive pulmonary disorder (COPD).
* The patient can be given supplemental (extra) oxygen through a mask.
* Sometimes, moist, hot air can help wheezing. Sitting in an area like a shower, or using a vaporizer (which creates moist, warm air) may be helpful for mild wheezing. Emergency medical technicians or hospitals can also give humidified oxygen, which is mixed with warm water to make the oxygen into a warm steam.
* There are medicines called bronchodilators that relax and open up the airways. This reverses the cause of wheezing and makes it easier to breathe. Albuterol is a very common bronchodilator and is carried on many ambulances. Bronchodilators can be given in inhalers or in a nebulizer (which mixes the medicine with warm water to make the medicine into steam).

### Stridor
Stridor is a high-pitched sound that usually happens when a person breathes in. It may sound a lot like wheezing. Medical professionals can tell the difference by listening to the throat with a stethoscope. If the sound they hear is louder in the throat, it is stridor, not wheezing.

Stridor is usually caused by something blocking the larynx (voice box). This can happen because:
* Congestive heart failure (CHF)
* Pneumonia or other infections in the lungs
* Injury to the lung
* Blood clot in the lung (pulmonary embolism)
* Breathing in smoke
* Drowning

Rales signals pulmonary edema, no matter what is causing that pulmonary edema. When a medical professional listens to the lungs, rales usually start at the bottom of the lungs. As the pulmonary edema gets worse and fluid fills the lungs more, rales can be heard closer and closer to the top of the lungs.

### Rhonchi (coarse crackles)
Rhonchi are also called coarse crackles, because they sound like coarse, rattling, crackling sounds. Rhonchi and rales can sound a lot alike. The main differences are:
* Rales start at the bottom of the lungs and can be heard farther up as the patient gets sicker. They are heard on both sides (in both lungs) together.
* Rhonchi are often heard just in certain spots in the lungs. They do not always start at the bottom of the lungs. They may be heard only on one side, or in different spots on both sides.

Rhonchi are usually caused by mucus in the bronchi, the tubes that lead to the lungs. For example, if a person has pneumonia, mucus can build up in their bronchi and the bronchi's airways, and cause rhonchi.
* A very bad injury to the lung
* Lung diseases like asthma, COPD, tuberculosis (TB), whooping cough, pneumonia, or cystic fibrosis
* Sometimes air blisters called blebs form on the top of the lungs. If these air blisters break, air can leak out of the lungs and cause the lung to collapse.
* Sometimes, a lung can collapse on its own. This is called a spontaneous pneumothorax.

A pneumothorax is often a medical emergency and needs to be treated in a hospital.

## Related pages 
* Combat medic
* Healthcare
* Lungs

## References