COPD: Emphysema

Please note there is no audio for this animation

In emphysema, exposure to an irritant over many years causes an inflammation in the lungs which causes the following changes:

• Loss of elasticity of the lungs. These changes cause the air sacs (alveoli) to close before you have fully exhaled. As a result, air gets trapped in the lungs and the lungs get bigger (hyper-inflated). As the lungs become hyper-inflated they elongate and flatten, which means the diaphragm does not work as well as it should.
• The respiratory muscles then have to work harder to get air in and out of your lungs. However, this does not mean that your oxygen levels are low because the breathing muscles around the chest are working harder to compensate. This extra effort can make the patient feel very tired.  This is why breathlessness and fatigue are common symptoms of COPD.
• The alveoli become permanently damaged (see video above). Alveolar capillary bed is reduced. Air may reach the periphery of the lungs but fail to make contact with the capillary blood. Ventilation may exceed perfusion in parts of the lung resulting in increased physiological dead air space.