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.
Another main cause of hypoxia is the body's decreased ability to move oxygen through the blood to your organs. This can be due to either a vascular problem, like an artery blockage that stops blood flow, or a heart problem that reduces the amount of blood being pumped, like bradycardia.