Definition

By Mayo Clinic Staff

Hypoxemia is a low level of oxygen in the blood. It starts in blood vessels called arteries. Hypoxemia isn't an illness or a condition. It's a sign of a problem tied to breathing or blood flow. It may lead to symptoms such as:

  • Shortness of breath.
  • Rapid breathing.
  • Fast or pounding heartbeat.
  • Confusion.

A healthy level of oxygen in the arteries is about 75 to 100 millimeters of mercury (mm Hg). Hypoxemia is any value under 60 mm Hg. Levels of oxygen and the waste gas carbon dioxide are measured with a blood sample taken from an artery. This is called an arterial blood gas test.

Most often, the amount of oxygen carried by red blood cells, called oxygen saturation, is measured first. It is measured with a medical device that clips to the finger, called a pulse oximeter. Healthy pulse oximeter values often range from 95% to 100%. Values under 90% are considered low.

Often, hypoxemia treatment involves receiving extra oxygen. This treatment is called supplemental oxygen or oxygen therapy. Other treatments focus on the cause of hypoxemia.

From Mayo Clinic to your inbox

Sign up for free, and stay up to date on research advancements, health tips and current health topics, like COVID-19, plus expertise on managing health. Click here for an email preview.

To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail.

March 24, 2023