What are your lungs made up of and how do they work?
Your two lungs fill your chest and sit on either side of your heart. The left lung is smaller than the right because it shares that side of the chest with your heart.
Your windpipe – also called your trachea – carries air into the lungs and out again when you breathe out. The windpipe divides into airways called bronchi. These branch into smaller and smaller airways. The smallest are too narrow to be seen with the naked eye. This is often called the bronchial tree. At the end of these tubes are tiny air sacs called alveoli. This is where gas exchange happens. Under a microscope, the inside of your lungs look like a giant sponge.
Mucus is produced in the walls of the small airways to help keep your lungs clean and well lubricated. It is moved by tiny hairs called cilia that line your airways. They move back and forth sweeping a thin layer of mucus out of your lungs and into your throat. Unwanted materials stick to the mucus. When it reaches the throat, it’s usually swallowed without you realising.
If your mucus builds up or if you have an inflammation, coughing can help to clear it from the airways.
Some people with lung diseases can have increased sputum which can be difficult to clear. Physiotherapy can help by teaching you different techniques to clear your sputum.
Adapted from BLF
Here is a presentation about Airway Clearance