What Is Blood Oxygen Saturation Level?
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Blood Oxygen Saturation Level - An Overview

Published on Dec 06, 2022 and last reviewed on Jun 07, 2023   -  5 min read


Blood oxygen saturation estimates blood oxygen levels by measuring oxygen concentration in the blood. Read on to know.

What Is Blood Oxygen Level?

The blood oxygen level measures the amount of oxygen the red blood cells carry. Maintaining a proper balance of oxygen-saturated blood is critical for overall health. Oxygen is primarily transported by the red blood cells, which collect it from the lungs and transfer it throughout the body. The body closely controls blood oxygen levels to ensure they remain within a precise range, allowing enough oxygen to reach every cell. On a cellular level, oxygen helps replace worn-out cells, provides energy, and supports the immune system, among other things. As a result, it is critical to monitor the blood oxygen level.

All the cells require oxygen to produce energy adequately, and the body needs the energy to perform all of its operations, including digestion and even thought. Because low blood oxygen levels (hypoxemia) can cause various catastrophic illnesses and damage different organ systems, particularly the brain and heart, the body closely regulates the amount of oxygen saturation in the blood.

Most toddlers and adults do not require blood oxygen monitoring. However, the oxygen level in an individual's blood shows how well the body transports oxygen from the lungs to the cells, which is crucial for their health.

What Tests Are Used to Measure Blood Oxygen Levels?

There are two primary methods for measuring or testing blood oxygen levels:

  1. Blood Test for Oxygen Levels: The blood oxygen level can be measured as part of a more comprehensive test known as an arterial blood gas (ABG) test. The amount of oxygen and carbon dioxide in the blood is measured by an ABG test. The test also examines the proportion of acids and bases in the blood, known as the pH balance. Excessive or fewer amounts of acid in the bloodstream might be hazardous to health.

  2. Pulse Oximetry: A pulse oximeter can also test blood oxygen saturation through a tiny clip worn either on the finger or toe. An oximeter shows how much oxygen is in the blood, known as the SpO2 level and heart rate. It is a simple and painless procedure to see if someone's blood oxygen level is dangerously low.

An oximeter does not give as much information about oxygen levels as a blood draw test.

What Are the Causes of Abnormal Oxygen Levels in the Blood?

Blood oxygen levels can become abnormal as a result of any of the following issues:

Suppose the blood oxygen level is not average, it may indicate that the body is not obtaining enough oxygen, not releasing enough carbon dioxide, and has an imbalance in blood pH (it could be too acidic or basic).

What Are the Symptoms of Abnormal Oxygen Levels in the Blood?

  • Headache.

  • Chest pain.

  • Disorientation.

  • Breathing difficulty.

  • Rapid heartbeat.

  • Coughing.

  • Wheezing.

  • Restlessness.

  • Elevated blood pressure.

  • Visual impairments.

  • A feeling of euphoria.

  • Confusion.

  • A bluish tint on skin, fingernails, or lips.

  • Cyanosis on the skin, fingernails, and lips (a sign of carbon monoxide poisoning).

What Is a Normal Blood Oxygen Level?

Normal oxygen saturation levels range from 97 to 99 percent in a healthy person breathing. A decreased blood oxygen saturation level is when it is less than 90 %. Blood oxygen saturation values of less than 90 % are considered abnormal and should be evaluated by a healthcare expert. When that level rises over the baseline, it is referred to as having high blood oxygen saturation.

What Are the Treatments for Abnormal Oxygen Levels?

Treatment for abnormal oxygen levels entails maintaining an average amount of oxygen in the blood, which is accomplished by:

  • Treating Underlying Conditions: The therapy's most significant long-term impact element is treating the source of hypoxemia. The drug is frequently administered by inhaler, which allows for breathing the medication into the lungs swiftly.

  • Oxygen Treatment: It involves receiving extra oxygen through an oxygen cylinder (which can be portable). The pressure of the given oxygen may be adjusted.

Is an Elevated Blood Oxygen Level a Sign of COVID-19?

COVID-19 has a variety of effects on humans. Infected patients have experienced various symptoms, from moderate to severe sickness. Some individuals infected with COVID-19 have low blood oxygen levels, but not all. Even though individuals have normal blood oxygen levels, they do not have COVID-19 when they have other symptoms. Similarly, those with low blood oxygen levels may not have COVID-19.

While an at-home pulse oximeter can be helpful in some cases, it has limitations and only indicates a tiny portion of the overall health. Therefore, there are also other methods used to make a COVID-19 diagnosis than an oximeter.

How Can an Elevated Oxygen Level Be Managed?

After recovering from abnormal blood oxygen levels, it will return to normal blood oxygen levels. Here are some lifestyle changes that can help avoid hypoxemia:

  • Exercising deep breathing.

  • Doing yoga.

  • Mild exercises such as walking and inhaling, and exhaling slowly.

  • Consume a nutritious, well-balanced diet.

  • Drink plenty of water.

  • Stop smoking.


A variety of situations can cause low blood oxygen levels. Treating the root cause will frequently increase blood oxygen levels. It is not required to constantly monitor the blood oxygen level unless an underlying health issue might impair the body's capacity to take in oxygen.

The oxygen level in the blood must be regularly monitored in patients with chronic lung diseases such as COPD (chronic obstructive pulmonary disease) and COVID-19. A pulse oximeter measurement is typically precise enough, although having a margin of error. If the body shows any symptoms of low blood oxygen levels or difficulty breathing, contact the healthcare professional as early as possible. People with low blood oxygen might also improve their lifestyle behaviors, such as food and exercise.

Last reviewed at:
07 Jun 2023  -  5 min read




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