Pulmonary Ventilation and Common Respiratory Diseases

Pulmonary Ventilation

Pulmonary ventilation is the process by which atmospheric air enters the interior of the lungs and then leaves them to the atmosphere.

The movements in and out of the air that occur in pulmonary ventilation are caused by the volume changes experienced by the lungs, mainly due to the action of two types of muscles:

• Diaphragm. It is a muscle that lies below the lungs and separates the chest from the abdomen. By moving up or down it changes the capacity of the rib cage, which houses the lungs, and this produces the breathing movements.
• Intercostal muscles. These are the muscles between the ribs. By contracting and relaxing, they move the ribs and vary the volume of the lungs.

Inspiration and Expiration

Pulmonary ventilation is accomplished through two movements: inspiration (air into the lungs) and expiration (air out of the lungs).

Respiratory System Diseases

All respiratory ducts are exposed to direct contact with the external environment and, therefore, are the gateway for a large number of diseases. The most common are infectious, i.e., those due to the action of viruses, bacteria and other microorganisms. However, there are also chronic diseases caused by unhealthy habits such as tobacco use (smoking).

Some of the most common diseases of the respiratory system are:

Bronchitis

Bronchitis is an inflammatory disease of the bronchi, often due to infection by bacteria or viruses, which causes breathing difficulties. It is characterized by abundant and persistent mucus, accompanied by a cough. In smokers, the irritant action of tobacco smoke usually makes bronchitis chronic. As this condition worsens, the person has increasing difficulty breathing, walking or performing physical exertion, and may need supplemental oxygen on a regular basis.

Asthma

Asthma is caused by temporary narrowing of the airways, causing oxygen deficiency in the tissues and making breathing difficult. It is due to allergic triggers (pollen, dust mites, dust, pollution, etc.), intense physical exercise, or respiratory infections. Symptoms include coughing, shortness of breath, and wheezing.

Tuberculosis

Tuberculosis is a contagious illness caused by a bacterium that destroys lung tissue. It is transmitted from person to person through the air. It can also affect other body parts such as the brain or kidneys. If left untreated, it can be fatal.

Colds and Influenza

Colds and influenza (flu) are highly contagious infections of the airways caused by viruses. There are no curative treatments for these conditions; they generally resolve on their own after several days. Common symptoms include fatigue, sneezing, abundant mucus production, and throat irritation. Influenza is usually more severe than a cold and is often accompanied by muscle aches, chills, and fever.