What is SPO2 or Oxygen Saturation?

What is SPO2?

SpO2, also known as Blood Oxygen Saturation, an estimate of the amount of oxygen in the blood. Which refers to the amount of oxygenated hemoglobin in the blood. Hemoglobin is a protein in red blood cells that transports oxygen and carbon dioxide. It is found inside red blood cells and gives them their red color. 

Understanding SpO2 and Normal Oxygen Levels

A measurement of your blood oxygen is called your oxygen saturation level. Your blood oxygen level is a measure of how much oxygen your red blood cells are carrying. Your body closely regulates your blood oxygen level. It is vital to your health to maintain the precise balance of oxygen-saturated blood.

A SpO2 reading of 95% or greater is generally considered to be a normal oxygen level. However, a SpO2 reading of 92% or less (at sea level) suggests that your blood is poorly saturated. Insufficient saturation can cause a range of adverse health conditions including chest pain, shortness of breath, and increased heart rate.

Measuring SpO2

There are two ways that the blood can be tested to ensure it contains normal oxygen levels. 

  • An arterial blood gas (ABG) test is a blood test and it’s called  Arterial blood gas. It also can detect the level of other gases in your blood, as well as the pH (acid/base level). An ABG is very accurate, but it’s invasive.
  • The most common way is to use a pulse-oximeter to measure the SpO2 levels in the blood. Pulse oximeters are relatively easy to use, are very accurate despite their low price point.

A measurement of your blood oxygen is called your oxygen saturation level. Good blood oxygenation is necessary to supply the energy your muscles need in order to function, which increases during activity. If your blood oxygen level is below-normal it is called hypoxemia and that could be a sign of poor blood oxygenation, also called hypoxia. Your doctor can provide recommendations as to what ranges of oxygen levels are acceptable for you.


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Uses and Benefits of Pulse Oximeters

A pulse oximeter is a device intended for the non-invasive measurement of arterial blood oxygen saturation (SpO2) and pulse rate. Oximeters are widely used in hospitals, medical clinics, operating rooms, and homes. Both oxygen saturation level and pulse rate are vital signs of a patient. Oximeters are inexpensive and can report an accurate reading within seconds. Speed is important especially in an emergency situation.

A pulse oximeter is used medically by patients with asthma, emphysema, chronic obstructive pulmonary disease (COPD), chronic obstructive airway diseases (COAD), and other respiratory conditions. Patients with serious respiratory problems should have their SpO2 levels check regularly and especially if they are not feeling well.

For many patients, doctors often recommend exercise to improve their physical state. However exercise can result in increasing shortness of breath, patients should monitor their oxygen saturation with pulse oximeters while exercising so they can adjust the pace as the oxygen saturation decreases.

Patients with serious cardiac conditions would often experience low SpO2 levels. Pulse oximeters would help them to monitor their conditions and use supplementary oxygen when required. Pleth graph produced by a pulse oximeter shows the change in blood volume during a heart pulse is often a good indication of certain heart conditions.

Pilots, mountain climbers, and people in high altitudes also use pulse oximeters to help guard against hypoxia.

Proper breathing techniques, such as pursed-lip breathing, can increase your oxygen saturation level. Lots of patients with low oxygen saturations are able to increase their saturations all the way up to 93% with good breathing techniques. Practice and pulse oximeter will help patients to achieve this level of efficiency.

The pulse oximeter can also help athletes in high altitude training. The reduction in oxygen level can increase red blood cells in athletes and help to increase his/her endurance.