When we first meet Dory, she's just swimming around minding her own business when suddenly she bumps into Marlin and instantly offers to help him hunt down his son.
Chronic obstructive pulmonary disease (COPD) is a leading cause of death and disability internationally. Alveolar hypoxia and consequent hypoxemia increase in prevalence as disease severity increases.
Emphysema is difficulty breathing due to air trapped in the lung, resulting in reduced lung capacity. Smoking is usually the cause, as it damages the linings of the air sacs in the lungs making them close. This leads to areas of trapped air in your lungs. Other causes may include coal dust and other pollutants.