Breath sounds facts for kids

Breath sounds are the noises air makes as it moves through your respiratory system. You might also hear them called lung sounds or respiratory sounds. Sometimes, you can hear them without any help. Other times, doctors and nurses need to use a special tool called a stethoscope to listen to your lungs and airways.

To understand breath sounds, medical experts use a method called auscultation. This means they listen carefully with a stethoscope. They listen while a person breathes in and out. They check both lungs, on the chest and the back. They start at the bottom and move up. They also notice if the sounds are high or low in pitch. And they listen to how loud the sounds are: soft, medium, loud, or very loud.

What Are Abnormal Breath Sounds?

There are many kinds of breath sounds that are not normal. These are called adventitious breath sounds. Each different type of abnormal sound can point to a different health problem. Here are some of the most common abnormal breath sounds:

Wheezing: A Whistling Sound

Wheezing usually sounds high-pitched, like a musical whistle. You often hear it first when someone is breathing out. If the problem gets worse, wheezing can happen when they breathe in and out.

Wheezing happens when the airways in your lungs become too narrow. This can be caused by conditions like asthma or chronic obstructive pulmonary disorder (COPD). When airways are too narrow, the oxygen your body needs cannot get through easily. This can become a serious medical emergency.

Here are some ways wheezing can be treated:

• Extra oxygen can be given through a mask.
• Sometimes, warm, moist air can help. Sitting in a steamy shower or using a vaporizer might help mild wheezing. Hospitals can also give oxygen mixed with warm water, making it a warm steam.
• Medicines called bronchodilators can relax and open up the airways. This helps reverse the cause of wheezing. Albuterol is a common bronchodilator. These medicines can be given with inhalers or a nebulizer (which turns the medicine into a mist).

Stridor: A Loud Breathing-In Sound

Stridor is a high-pitched sound that usually happens when a person breathes in. It might sound a lot like wheezing. However, medical professionals can tell the difference. They listen to the throat with a stethoscope. If the sound is louder in the throat, it's stridor, not wheezing.

Stridor is often caused by something blocking the larynx (your voice box). This can happen if:

• A person is choking, and an object blocks the larynx.
• An infection causes swelling in the throat or airways.
• The muscles in the airway or vocal cords suddenly tighten (this is called laryngospasm).

Like wheezing, stridor can be a medical emergency if not enough oxygen can get into the body.

Treatment for stridor depends on what caused it:

• Helping someone stop choking, for example, with the Heimlich maneuver.
• Treating the infection that caused swelling in the larynx.
• Giving medicines to help airway or vocal cord muscles relax.
• No matter the cause, giving extra oxygen can also help.

Children are more likely to have stridor from choking because their airways are smaller. They are also more likely to get childhood infections like croup or epiglottitis, which can cause stridor.

Rales (Fine Crackles): Fluid in the Lungs

Rales are also called fine crackles because they often sound like a soft crackling noise. You hear them when a person breathes in, on both sides of the chest (in both lungs). Rales can also sound like bubbling, rattling, or small clicking sounds.

Rales are heard when there is fluid in the lungs. This is called pulmonary edema. Pulmonary edema can happen for many reasons, such as:

• Congestive heart failure (CHF).
• Pneumonia or other lung infections.
• An injury to the lung.
• A blood clot in the lung (pulmonary embolism).
• Breathing in smoke.
• Nearly drowning.

Rales always signal pulmonary edema, no matter what caused it. When a doctor listens to the lungs, rales usually start at the bottom. As the fluid fills more of the lungs, rales can be heard higher up.

Rhonchi (Coarse Crackles): Mucus Sounds

Rhonchi are also called coarse crackles because they sound like rough, rattling, crackling noises. Rhonchi and rales can sound quite similar. The main differences are:

• Rales start at the bottom of the lungs and move up as a person gets sicker. They are heard in both lungs at the same time.
• Rhonchi are often heard only in certain parts of the lungs. They don't always start at the bottom. They might be heard on just one side, or in different spots on both sides.

Rhonchi are usually caused by mucus in the bronchi. The bronchi are the tubes that lead to your lungs. For example, if someone has pneumonia, mucus can build up in their bronchi and airways, causing rhonchi.

Unequal Breath Sounds: A Lung Problem

In a healthy person, breath sounds should always sound the same on both sides of the chest. This shows that both lungs are working well. If breath sounds cannot be heard in one lung, it can mean a serious problem. It means air is not getting in and out of that lung.

One common reason for unequal breath sounds is a collapsed lung (pneumothorax). A lung can collapse for many reasons:

• 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 top of the lungs. If these break, air can leak out 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 treatment in a hospital.