Hypoxemia: Definition, Symptoms and Treatment

Health professional administering oxygen

Your blood carries oxygen throughout your body, and it controls the amount of oxygen pretty precisely. When you don't have enough oxygen in your blood, that condition is known as hypoxemia.

Hypoxemia appears to be relatively common in people with advanced chronic obstructive pulmonary disease (COPD). It also can result from other lung conditions, such as lung cancer, pneumonia, asthma and bronchitis.

Oxygen blood level is measured in millimeters of mercury (mm Hg), and a normal oxygen level in your arteries is about 75 to 100 mm Hg. People with COPD have lower levels. If you have a very low level, you may need supplemental oxygen. However, providing too much oxygen can be dangerous, too, so your doctor will need to work with you to get the correct balance.

It's also possible to use pulse oximetry to measure your blood oxygen level at home. Talk to your doctor about what readings you should expect from pulse oximetry and when to seek medical help for a low reading.

Symptoms of Hypoxemia

Symptoms of hypoxemia include confusion, shortness of breath and increases in your blood pressure and your heart rate as your body tries to compensate for the low oxygen in your blood stream. People with COPD who suffer from hypoxemia when they're at rest are more likely to have problems concentrating or remembering things, and those problems get worse as their hypoxemia worsens.

In severe hypoxemia, you might start to sweat or wheeze, your skin may get cold and clammy, and you may start to turn blue. This last symptom, called cyanosis, indicates there's not enough blood with oxygen reaching your cells. These symptoms indicate an emergency situation, and you should seek help immediately.

Hypoxemia often leads to hypoxia, which means you don't have enough oxygen getting to your tissues. In fact, many people confuse the term "hypoxemia" with the term "hypoxia," but the two are not the same — hypoxemia refers to low oxygen in your blood, while hypoxia refers to low oxygen in your tissues.

It's possible to have hypoxemia without hypoxia, if your body compensates for your low blood levels of oxygen by boosting the amount of oxygen that actually reaches your tissues (for example, by making your heart beat faster to move oxygen-carrying blood around more quickly). It's also possible to have hypoxia without hypoxemia, if the actual oxygen delivery to your cells isn't working properly, or if your cells aren't able to use the oxygen properly.

What to Do If You Suspect Hypoxemia

Severe hypoxemia is a medical emergency. If you have symptoms of severe hypoxemia, especially if you have COPD or another illness that predisposes you to hypoxemia, seek emergency care immediately.

If your medical testing indicates you have chronic hypoxemia, your doctor may recommend you go on supplemental oxygen.

However, supplemental oxygen doesn't help everyone, so you'll need to discuss the pros and cons with your doctor.

Some people with COPD suffer from hypoxemia at night. This occurs because of breathing changes during sleep that decrease the amount of oxygen reaching your blood stream. In people without COPD, these breathing changes don't have such an effect, but in people who have COPD, they can cause hypoxemia. COPD patients with mild hypoxemia problems during the day may be more prone to hypoxemia at night. Talk to your doctor if you're having symptoms at night.


Kent BD et al. Hypoxemia in patients with COPD: cause, effects, and disease progression. International Journal of Chronic Obstructive Pulmonary Disease. 2011; 6: 199–208.

Stoller JK et al. Chronic Obstructive Pulmonary Disease. Cleveland Clinic Center for Continuing Medical Education. October 2012.

Continue Reading