Lung Health Basics

What to Know About Lungs and Breathing

Boost your lung health literacy by learning about these basic lung anatomy terms and 

conditions. This resource also describes some of the tests doctors use to see how well the 

lungs are working, plus treatment devices and methods to help those with lung conditions 

breathe easier.

General Lung Terms

General Lung Terms

• Lungs

• Pulmonary

• Respiratory 

system

• Gas exchange

• Oxygen

• Airways

• Alveoli

• Ventilation

The lungs are the pair of pinkish-gray, spongy organs in your 

chest. They supply your body with oxygen and remove carbon 

dioxide, a waste gas, from your body.

Pulmonary means having to do with the lungs.

The respiratory system is made up of the organs that are 

involved in breathing. These include the nose, throat, larynx 

(voice box), trachea (windpipe), and lungs.

Gas exchange happens 

when you breathe. 

Oxygen moves from 

your lungs to your blood 

and carbon dioxide 

moves from your blood 

to your lungs.

Carbon Dioxide

Oxygen

Oxygen is a colorless, odorless gas that is needed for plant and 

animal life. Oxygen that you breathe in enters the blood from the 

lungs and travels to the tissues.

The airways are tubes that carry air in and out of your lungs.

Alveoli are tiny air sacs at the end of the branches of air tubes in your lungs where oxygen enters 

the blood and carbon dioxide leaves the blood.

Pulmonary ventilation is another term for breathing. It is the process of air flowing into the lungs 

while inhaling and out of the lungs while exhaling.

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Lung Diseases and Conditions

Lung Diseases and 

Conditions

• Asthma

• COPD

• Cystic fibrosis

• Pulmonary 

fibrosis

• Sarcoidosis

• Bronchiectasis

Asthma is a long-term 

condition that causes 

the airways to narrow 

at times from certain 

triggers that cause 

inflammation.

Chronic obstructive 

pulmonary disease 

(COPD) is a lung 

disease in which less 

air flows in and out of 

the airways. This makes 

breathing difficult. The 

term “COPD” includes 

2 main conditions: 

emphysema and chronic bronchitis.

Cystic fibrosis is a disease that affects the lungs and other 

organs. It causes a buildup of mucus, which can lead to 

blockages of mucus, infections, and damage in the lungs, 

making it harder to breathe.

Pulmonary fibrosis is a disease in which the tissue in the lungs 

becomes thick and stiff. Over time, this can cause permanent 

scarring (fibrosis) in the lungs, making it more difficult to 

breathe.

Sarcoidosis is a disease that develops when groups of cells in 

your immune system lump together to form red and swollen 

collections of cells called granulomas. Sarcoidosis can affect 

any organ, but most often affects the lungs and lymph nodes 

in the chest.

Bronchiectasis is a condition in which the airways become 

damaged, causing them to become loose and scarred. This 

makes it hard to clear mucus from the airways, which can lead 

to frequent serious lung infections.

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Lung Diseases and 

Conditions

• ARDS 

• Pneumonia

• Pulmonary 

hypertension

Acute respiratory distress 

syndrome (ARDS) is a 

serious lung condition in 

which fluid builds up in the 

air sacs in the lungs. This 

prevents the lungs from 

properly filling with enough 

air to breathe normally. 

Over time, the lung tissue 

can become scarred and 

stiff, making it harder to 

breathe.

Air sac filled with fluid

Pneumonia is an infection in which the air sacs of one or both 

lungs fill up with fluid or pus, which interferes with breathing. 

Bacteria, viruses, or fungus may cause pneumonia.

Pulmonary hypertension is high blood pressure in the blood 

vessels leading from the heart to the lungs. This makes the right 

side of the heart pump harder against that pressure buildup 

within the blood vessels in the lungs. This can cause shortness 

of breath and low oxygen levels in the blood.

Monitoring and Testing

Monitoring and 

Testing

• Lung volume 

test

• FeNO test

• Spirometry

• Peak flow meter

• ABG test

A lung volume test measures how much air the lungs can hold. It is 

the most accurate way to measure the volume of air in the lungs. 

Fractional exhaled nitric oxide (FeNO) tests determine how inflamed 

the airways are by measuring how much nitric oxide is in your breath. 

Nitric oxide levels are often higher with certain types of inflammation.

Spirometry is a breathing test 

that measures lung function 

by testing how fast and how 

much air you are able to 

breathe in and out.

A peak flow meter is a 

small device that shows 

how well you blow air out 

of your lungs.

An arterial blood gas (ABG) test measures the 

amount of oxygen, carbon dioxide, and acidity in 

your blood. It is used to check for serious breathing 

problems or other health conditions.

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Monitoring and 

Testing

• Six-minute walk 

test

• CPET test

• Asthma action 

plan

The six-minute walk test

is a way to measure your 

ability to exercise. You will 

walk as far as possible in six 

minutes. Your healthcare 

provider will measure your 

oxygen levels, heart rate, 

blood pressure, and the 

distance you walked. This 

test is commonly used 

for people with COPD or 

pulmonary hypertension. 

A cardiopulmonary exercise test (CPET) is used to collect 

information about the body while at rest, and with increasing 

levels of exercise, to understand how the heart, lungs, and 

muscles are responding to exercise. 

An asthma action plan is a worksheet you fill out with your 

healthcare provider to help you monitor asthma and treat 

changing symptoms or attacks. It serves as a guide for you 

and your family when you are well and when you are having 

symptoms or asthma attacks.

Treatment Devices and Methods

Treatment Devic

and Methods

es 

• Nebulizer

• Dry powder 

inhaler

• Metered-dose 

inhaler

• Pulmonary 

rehabilitation 

• Oxygen therapy

A nebulizer is a machine that delivers a fine, steady mist of medicine 

through a mouthpiece or mask.

A dry powder inhaler contains pre-set doses of medicine in powder 

form. When you take a deep, fast breath in from the inhaler, the 

medicine is released into your airways.

A metered-dose inhaler contains a 

canister of medicine. When you press 

the inhaler, it sprays a pre-set amount 

of medicine through your mouth to 

your airways.

Pulmonary rehabilitation is a 

supervised medical program 

that helps people who have 

lung diseases like COPD live 

and breathe better. It involves 

exercises, breathing techniques, nutrition 

counseling, and mental health counseling. 

Oxygen therapy is a treatment that delivers oxygen for you to 

breathe. You can receive oxygen therapy from tubes resting in your 

nose, a face mask, or a tube placed in your trachea (windpipe).

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