What is oxygen therapy?
Oxygen therapy helps people with lung diseases or breathing problems get the oxygen their bodies need to function. This oxygen is supplemental (additional) to what you breathe in from the air. You may also hear the term supplemental oxygen.
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Who needs oxygen therapy?
You may need oxygen therapy if you have:
- Asthma, bronchitis or emphysema.
- Chronic obstructive pulmonary disease (COPD).
- COVID-19.
- Cystic fibrosis.
- Heart failure.
- Lung cancer or other cancers.
- Pneumonia.
- Pulmonary fibrosis.
- Sleep apnea.
People who live in or visit high-altitude areas may also need supplemental oxygen, including mountain climbers. Oxygen levels in the air are lower in high-altitude locations, which can lead to altitude sickness.
What does oxygen therapy do?
Oxygen therapy gives your body the oxygen it’s not getting when you breathe in air. You might think of it as a respiratory system aid.
When you breathe through your mouth or nose, your body takes in air. Air contains 80% nitrogen and 20% oxygen. Your lungs filter oxygen from this air. They then send oxygen through blood vessels to your organs, tissues and cells.
When you have lung problems, not enough oxygen reaches your cells to keep your body and organs working as they should. You develop low blood oxygen levels (hypoxemia). Over time, hypoxemia can lead to organ damage and organ failure. Lack of oxygen can be life-threatening.
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What are healthy oxygen levels?
A healthy oxygen level (also called oxygen saturation) is 95% or higher. Healthcare providers prescribe oxygen therapy when oxygen levels drop below 88%.
Providers use these tests to measure oxygen levels:
- Pulse oximeter: This small device painlessly clips onto your finger, toe or earlobe. Sensors in the device send light beams through your skin to measure oxygen levels in capillaries (tiny blood vessels). Many providers routinely perform this test at each appointment. You can also buy a pulse oximeter (pulse ox) at drugstores to use at home.
- Arterial blood gas test: This test uses a blood sample from an artery to measure oxygen and carbon dioxide levels in your blood. This test is the most accurate method for determining lung function.
- Lung function tests: Pulmonary function tests like spirometry measure how well you inhale and exhale air. Some tests also measure your lungs’ ability to send oxygen into your cells.
What are signs of low oxygen levels (hypoxia)?
You can’t always tell when your oxygen levels are low. When symptoms occur, you may experience:
- Shortness of breath.
- Bluish tint to skin, lips and nails.
- Extreme fatigue.
- Severe headaches.
- Coughing or wheezing.
- Fast pulse and heart rate.
- Confusion.