Lung disease – Pulmonary Fibrosis
Pulmonary fibrosis due to the scar from an epithelium of the lung causing it to become reversibly thick. In order for diffusion to occur the alveoli needs to be thin. A person suffering from pulmonary fibrosis cannot diffuse in the blood efficiently as the pathway has been lengthened. The volume of air in the lung also decreases. Fibrosis also reduces the efficiency of the elasticity of the lungs. Fibrosis makes it difficult to breathe in and out and therefore to ventilate. Someone with fibrosis experiences:
1. Shortness of breathe, especially when exercising, due to the great amount of volume the air space in the lung is occupied by the fibrous tissue. This means therefore that less air in inhaled. Also the epithelium of the alveoli has thickened; this increases the diffusion pathway so diffusion into the blood is considerably slow. This contributes to the loss of elasticity makes the ventilation very hard. Resulting in little diffusion gradient.
2. Dry cough, fibrous tissue creates an obstruction in the air ways of the lungs. The body’s reflex reaction to remove anything in its way so this means that as there is nothing to remove the cough is though to be ‘dry’
3. Weakness and fatigue, this is as a result from the reduced intake of oxygen into the blood. Meaning that the release of energy is reduced, leading to tiredness.
4. pain and discomfort in the chest this is a consequence of pressure and damage from the mass of fibrous tissue in the lungs, it is also due to scaring from the dry cough.
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