Any level of reduced oxygen carries risks for people with emphysema, according to The New York Times. The level of danger for the patient depends on the stage of the condition.
The first symptoms of reduced oxygen levels in people with emphysema include shortness of breath, coughing and lightheadedness, according to The New York Times. The more advanced symptoms of emphysema include a craving for air, lung inflammation, involuntary weight loss and muscle wasting. During the later stages of emphysema, the effects of reduced oxygen levels can include respiratory failure, pulmonary hypertension and brain damage.
In describing emphysema, WebMD explains two staging systems used for the condition. The GOLD staging system divides the condition into four stages based on the amount of air that a patient can exhale in one second. The other system, known as the BODE index, includes factors that affect other areas of life, such as body mass index and exercise capacity.