Lungs

The lungs are the body's respiratory organs. They are located in the chest and are surrounded by the ribs. Thanks to the lungs we can absorb oxygen from inhaled air. The lungs also remove waste products via the exhaled air.

Anatomy of the lungs

Humans have two lungs, a left lung and a right lung. There are, however, some anatomical differences between the two. The left lung is slightly smaller than the right because the heart is largely located on the left side. The left lung consists of two lobes, the right lung of three.

As the image shows, the lungs resemble an upside-down tree inside a bag. From top to bottom, there is first the trachea. This is the 'trunk.' It carries inhaled air from the nasal or oral cavity toward the lungs. At the end of the trachea are the bronchi, which in this example are the branches and form the entrance to the lungs.

Once inside the lungs, the bronchi branch about ten more times. In addition to distributing oxygen, the bronchi also have the important task of filtering inhaled dust particles and bacteria. At the ends of the branches lie the alveoli, or air sacs. These are tiny sacs of cells where gas exchange takes place between the inhaled air and waste products, mainly carbon dioxide (CO2), in the blood.

Function of the lungs

The respiratory system therefore consists of the nasal cavity and oral cavity, pharynx, trachea, bronchi, and alveoli. Together, they supply the body with oxygen (O2). At the same time, they ensure that carbon dioxide is removed from the blood. Inhaled air contains only 20% oxygen and 79% nitrogen. This nitrogen is an inert gas.

In healthy lungs, the process of gas exchange happens on average about 15 to 20 times per minute. This means the lungs process about 0.5 liters of inhaled air every 3 to 4 seconds.

The many millions of alveoli have thin, elastic walls. The exchange of oxygen and waste products occurs via a network of very small blood vessels that surround the alveoli.

Respiratory center

The brain contains the so-called respiratory center. This center ensures that the carbon dioxide and oxygen levels in the body remain constant. This happens automatically.

When the carbon dioxide level in the alveoli reaches a certain threshold, a nerve signal is sent to the respiratory center. This immediately sends a command to the respiratory system to inhale with the help of the respiratory muscles. Gas exchange as a result of this 'breath' ensures that the amount of carbon dioxide in the alveoli decreases again. This process repeats as soon as the carbon dioxide level rises again.

Diseases of the lungs

A problem with the lungs or the airways can have major consequences, because proper functioning of the lungs is vital. A common lung disease is asthma. In asthma, the lungs are inflamed, making it difficult for patients to breathe.

Another common lung disease is COPD. This is a collective term for chronic lung diseases in which the lungs are damaged. Two important lung diseases that fall under this are bronchitis and emphysema.

In pneumonia, the lower airways are inflamed, mainly the alveoli and the surrounding tissue. The body tries to clear the bacteria or virus that is causing problems. This process can cause mucus to form in the lungs, which, together with irritation of the lungs, results in coughing and shortness of breath.

A pulmonary embolism is the blockage of the pulmonary artery, reducing oxygen uptake in the lung. A blood clot that formed elsewhere in the body in the bloodstream is usually the cause.

Treatment of lung problems

Lung problems can be treated by various specialists. Usually, the first point of contact is the family doctor. For mild lung problems, the family doctor can provide advice or prescribe medication. In other cases, the family doctor can refer patients to a pulmonologist or a respiratory physical therapist.