The meaning of saturation, also called oxygen saturation, is the percentage of oxygen content (SpO2 %) that has bound to the hemoglobin in the blood. In medical terms, saturation means the saturation of the % oxygen molecules (O2) and carbon dioxide (CO2) bound to the protein hemoglobin in the red blood cells. Popularly we say the percentage of oxygen content in the blood.
You can easily measure saturation yourself with a pulse oximeter, also called a oxygen meter or oxygen saturation meter. You usually place this device on your finger. Within a few seconds you will see the percentage on the screen.
Saturation is indicated as a percentage of SpO2. The Sp stands for saturation. The O2 stands for the oxygen molecules. An SpO2 % of 95% or higher is considered normal saturation (healthy oxygen values) for a standard person.
In children (12 years or younger) the percentage (SpO2) saturation value will be slightly higher compared to adults. There the percentage will be closer to 100%. This is because children are often more active and as a result they take in more oxygen.
A saturation value lower than 90% is called desaturation. In medical terms this is called hypoxemia. An SpO2 % lower than 90% is alarming. With these saturation values you should in principle contact a doctor immediately and have yourself examined.
Lower values are more common in people who suffer from a lung disease such as asthma or COPD.
During the day the percentage of oxygen can fluctuate. If you have a slightly lower percentage, but above 90%, it is recommended to measure more often to keep a close eye on it.
How to measure saturation?
Saturation is measured by means of a pulse oximeter. A pulse oximeter or oxygen meter measures the oxygen content by means of a sensor. This sensor consists of 2 parts: an infrared light source and a photosensor. The infrared light source emits an infrared beam that looks at the color of the blood.
Iron in the hemoglobin gives the blood its red color. The connection of hemoglobin with oxygen molecules gives a different color red than when more or less oxygen molecules are bound. The reflected infrared rays are different from the emitted infrared rays. The photosensor can accurately determine to what extent the hemoglobin is bound to oxygen.
Saturation is often measured at the fingertip. Various small blood vessels run through the fingertip that are clearly visible. This is because the skin on the fingertip is relatively thin.
Saturation with corona
Measuring saturation is very important for people with corona. Corona (Covid-19) is a lung disease. In case of an infection, it will be more difficult for oxygen to be absorbed into the red blood cells. The coronavirus can create a barrier of moisture in your lungs. It’s much harder for oxygen to pass through this.
Many corona patients have a saturation of less than 92% SpO2. This can be very life-threatening. It is therefore highly recommended to measure saturation frequently.
In collaboration with various Amsterdam hospitals and general practitioners, we have supplied many pulse oximeters to Covid-19 patients. This allows them to easily measure saturation at home. This shortens the hospital visit by more than 2 days. The pulse oximeter that we have supplied is the iHealth Air Smart pulse oximeter. This excellent model measures saturation very accurately and can be connected to your smartphone. With a special saturation measuring app it is very easy to exchange the measured saturation values.
Low saturation symptoms
If you suffer from low saturation, you will experience a number of complaints. The main symptoms of low saturation are:
- Increased heartrate
- Shortness of breath
The above symptoms are often the first indications of low oxygen saturation. If the saturation values remain low for a longer period of time, you can become tired, short of breath or even confused due to lack of oxygen.