Pulmonary fibrosis is a disease that affects the lungs. The lung tissue becomes damaged and scarred which causes it to be thickened and stiff.
The condition pulmonary fibrosis is caused by the replacement of elastic fibers in the lung with inelastic collagen fibers. This decreases the lungs’ ability to stretch outwards.
Pulmonary fibrosis however mainly affects inspiration because the lungs cannot stretch to increase volume while during expiration stretching of the tissues doesn’t happen so it doesn’t affect the process.
The ability if the lungs to stretch due to contraction of inter coastal muscles ensures that maximum air enters the lungs as the lungs expands, and enough oxygen enter the alveoli to reach the blood,this is inspiration.
If inelastic collagen fibres replaces the elastic fibres, the failure of the lung to stretch outwards,increase in volume, deceases the lung capacity, thus maximum filling inspiration is prevented, and therefore low oxygen supplies to the needed organs.
