Every cell in your body needs oxygen to live and do its job properly. Your blood's job is to bring this precious oxygen to your cells. Sometimes, however, the level of oxygen in your blood can fall below normal — a condition known as hypoxemia.
Hypoxemia can be mild or severe. If severe, without treatment, it can be fatal, according to the Mayo Clinic.
Signs of Hypoxemia
One of the most common symptoms of low blood oxygen is shortness of breath, says Louis R. DePalo, MD, a professor of pulmonary medicine and critical care medicine at the Icahn School of Medicine in New York. Other symptoms include headaches, light-headedness, rapid breathing, anxiety and a slow heart rate, even in people who are otherwise very healthy, he adds. Your skin, lips and fingernails also may look bluish.
People with medical problems such as asthma, chronic obstructive pulmonary disease (COPD) and heart failure might also experience chest pain, confusion and slurred speech when having an episode of hypoxemia. "They might also have wheezing and congested cough," Dr. DePalo says.
Severe hypoxemia is a very serious condition. You can lose consciousness within 15 seconds of your brain being deprived of oxygen, and after 4 minutes without oxygen, you start to experience brain damage, according to Headway, the Brain Injury Association of the UK.
Causes of Hypoxemia
A number of different heart and lung conditions can impede your blood's ability to deliver adequate oxygen, according to the Cleveland Clinic. These include:
- Heart problems
- Pulmonary fibrosis (inflammation or scarring of lung tissue)
Strong pain medication like narcotics also can cause your breathing to slow. So can sleep apnea, a condition that causes you to stop breathing for numerous short spurts while you're sleeping. It's also possible for it to occur when you're at a high altitude, like on a ski vacation in the Rockies.
When to Seek Medical Attention
If you experience shortness of breath for no obvious reason, get medical attention. Your doctor will listen to your heart and lungs, check the color of your skin, lips or fingernails and use certain tests to determine your blood oxygen levels, according to the Cleveland Clinic. These may include:
- Pulse oximetry. This simply requires placing a painless sensor on your finger that measures the oxygen in your blood.
- Arterial blood gas test. This test involves taking a blood sample. The sample is analyzed in a lab by technicians using specialized equipment that measures your blood oxygen level.
- Pulmonary function tests. These tests, which are not painful, measure how much air your lungs can hold. The most common is spirometry, which involves breathing into a tube, according to the American Lung Association.
How Hypoxemia is Treated
First and foremost is to give oxygen as needed, Dr. DePalo says. You may be given oxygen through a breathing mask or a tube called a cannula, which can be clipped to the outside of your nose, according to the Cleveland Clinic. Depending on how severe your situation is, you may need to be hospitalized to receive oxygen. If you need oxygen long-term, you may be given a portable oxygen tank that can travel with you.
Once you are stable and breathing better, it's important to determine what caused your hypoxemia, Dr. DePalo says. More specific treatment depends on the underlying circumstances that led to the low blood oxygen level.
For instance, if it's due to being at a higher than normal altitude, where there's less oxygen in the air, you'll need to move to a lower altitude, he says. If it's from asthma or COPD, you'll need to be treated for wheezing. If it's from heart failure, you might be prescribed diuretics, which help remove fluid from your lungs and make it easier to breathe.
Read more: Can Vitamins Increase Blood Oxygen Level?
Help Prevent Hypoxemia
If you are prone to shortness of breath due to hypoxemia, it's important that you take steps to lower your risk. According to Mayo Clinic, doing these things can help:
- Quit smoking. If you have any lung disease or trouble breathing, you should not smoke. It's that simple.
- Avoid second-hand smoke. When your lungs are weak, just being around smoke can do damage. Stay away from people who smoke.
- Get moving. You may be reluctant to exercise when you have breathing difficulties, but regular exercise can strengthen your lungs and help you build endurance.
Is This an Emergency?
- The Mayo Clinic: “Hypoxemia”
- Cleveland Clinic: “Hypoxemia”
- Cleveland Clinic: “Can Hypoxemia Be Prevented?”
- Louis R. DePalo, MD, professor, pulmonary and critical care medicine, Icahn School of Medicine, New York.
- American Lung Association: “Lung Function Tests”
- Headway: “Hypoxic and Anoxic Brain Injury”
- Cleveland Clinic:"Hypoxemia: Diagnosis and Tests"
- Cleveland Clinic: "Hypoxemia: Management and Treatment"
- Mayo Clinic: "Hypoxemia: When to See a Doctor"