The bronchi are the lining of the air tubes of the lungs. The inflammation of the bronchi is called Bronchitis. It can be the result of a cold, a sore throat or influentza. The cool air and the low temperatures in winter influence in a negative way the disease. You can be contaminated with the virus that causes Bronchitis by breathing a polluted atmosphere or by smoking.

The symptoms last for one or two weeks, but this period is longer and the Bronchitis becomes chronic in cigarette smokers. They manifest also inevitable winter flare -ups.

Using a microscope we can have the image of the cells in the healthy lungs. These cells looks tall, columnar and their surface is covered with cilia which are able to move creating the image of a wind blowing across a field of ripe corn. This surface covered with cilia is near the inside of the tube and it has the role to protect the lungs. This protection is possible because the movement of the cilia carry dust and other foreign materials upwards and away from the delicate air sacs from the lungs.

The ciliated cells can be damaged by different external irritants such as cigarette smoke, industrial pollutants and other chemical substances. So the effect of the movement of the cilia is not giving results anymore. As a consequence the glands produce a high quantity of mucus which can't be evacuated and it is accumulated in the tubes. This is one of the causes of the persistent cough which characterizes Bronchitis. Usually this cough succeed to clear the mucus. Another way of protection of the lungs is the action of the Leucocytes whose principal role is to combat inflammatory processes.

Another sign of chronic bronchitis is the weezing. It is produced by the bronchospasm which is represented by the contraction of the circular muscles in the wall of the bronchial tubes.If this happenes the coughing becomes less efective too.

Bronchitis takes part of the disease grouped under COPD which means chronic obstructive pulmonary disease. If the disease doesn't respond to treatment it can progress to COAD (chronic obstructive airway disease). In this case tiny lung air sacs break down to form larger air spaces. At the same time, because of this change, the surface area available for the transfer of the oxygen to the blood is much less. So the other organs are less oxygenated. the mucus block the smaller bronchial tubes which becomes inflamed.

In this circumstances smoking becomes more dangerous. Another disease which takes part of the category of COPD is Emphysema. Bronchitis and Emphysema lead to breathlessness. Anothe aspect is that it is restricted the quantity of the oxygen that reaches to the blood. This blood without enough oxygen is blue and it gives a bluish tinge to the skin. In medicine this color of the skin is called cyanosis. This is a very helpful sign for the diagnosis.

The heart is also affected in Bronchitis. The right heart enlarges. There is an extra pumping power because of the increase of the resistance to blood pumped through the lungs. The consequence is the oedema which is an exaggerated accumulation of liquid in the interstitial space.