A pulse oximeter is a very useful gadget for anyone who wants to know the level of oxygen in their blood as well as their pulse rate. It uses the principle of pulse oximetry which uses red and infrared light.
What Are The 2 Readings on A Pulse Oximeter?
A pulse oximeter has become a very common device for use at home due to its ease of use, accuracy, and affordability. You are most likely having one of these devices with you at these uncertain times and already placing it on your finger or earlobes to take some readings.
If you are wondering, what are the 2 readings on a pulse oximeter; they are the oxygen saturation percentage of blood (Sp02%) and the pulse rate (bpm).
The Blood Oxygen Saturation (SpO2) is a measurement that shows how saturated the blood is with oxygen. Whereas the pulse rate is basically the heart rate and shows how many heartbeats are recorded per minute.
Interpreting Pulse Oximeter Readings (Including Normal Range)
To answer the common question; what is normal Sp02 and pr bpm? The normal blood oxygen saturation level is considered to be anything between 95% and 100% (Sp02%). When the values fall under 95%,they are considered to be low.
For the pulse rate, the normal range is 50 to 90 beats per minute (bpm) depending on human physical activities. If the heart rate surpasses 100 one may need to seek professional help.
How a Pulse Oximeter Works
The most common type of an oximeter is the fingertip type (used on a finger), however other types exist including one which can be used on the earlobe. Pulse oximetry is categorized as a noninvasive test because no pricking is required.
A pulse oximeter uses both red and near infrared light to determine the state of the blood. It shines the 2 lights through a finger. Blood that contains a lot of oxygen tends to absorb more infrared while allowing more red light to pass right through.
The extent of absorption of the red and infrared light is measured by receivers on the device which has been calibrated. This results in the display of different figures on the device.
How to Measure Oxygen Level at Home using an Oximeter
To check your oxygen level at home we recommend having a good quality fingertip pulse oximeter like this one. A fingertip device is easy to insert and make readings as compared to an earlobe one where one might need assistance from another person.
Things to observe when using a fingertip pulse oximeter include:
- Ensure the nail you are going to insert in the fingertip oximeter does not nail polish or henna or even a tattoo as those can affect the functioning of the device
- Warm-up your hands and/ or fingers before using the device e.g. by flexing or rubbing your hands together.
- Make sure you are seated and relaxed (for at least 5 minutes) before taking the measurements.
- Check if the pulse oximeter has some batteries
- Switch the pulse oximeter on by pressing the button usually at the top
- Place the oximeter clip on the end of your finger, it usually works best on your middle finger or index finger. Sometimes the clip is placed on a toe or an earlobe.
- The oximeter device will shine a light beam through the skin. It will then calculate and estimate the percentage of your blood that is carrying oxygen.
- Keep the pulse oximeter on the finger for at least one minute until the oxygen level reading stabilizes. If the readings keep changing, ta
- The oxygen level (%Sp02, oxygen saturation) shows on the display screen. It is good to know the normal oxygen levels of 95 -100 Sp02 and compare the oximeter readings.
Pulse Oximeter Readings Chart
Below are the typical pulse oximeter readings as per a professional MD’s scale. It shows what are considered to be the normal readings of pulse oximeter and which readings should trigger one to seek professional or emergency services.
|Measurement||Oxygen Saturation (Sp02%)||Pulse Rate
|Normal Readings||96-100 %||40 -80|
|Acceptable Levels and safe for home monitoring||95%||101 – 109|
|Contact professional MD||93-94%||110-130|
|An emergency||Less than 92%||More than 131|
It is always good to note that despite the readings they obtain from their pulse oximeter, it is always good to contact an MD for a comprehensive test.
The Accuracy of Pulse Oximeter for Heart Rate
A good number of people usually wonder, but what is the Pulse oximeter heart rate accuracy for a device that is very common for home use? The oximeter has an accuracy of ±2% when measuring oxygen concentration SpO2 in the range of 70%–99%. This has been confirmed by this scientific study on Science Direct.
For the geeks, a linear regression analysis showed that a pulse oximeter’s readings are r = 0.91, P less than 0.0001 which is correlated to what is produced by an electrocardiogram (ECG).
The accuracy of the device has made it very popular for people who want to explore oximeter readings Covid. This usually applies to people at risk as the condition causes a change in blood oxygen levels.
I believe now you are no longer wondering what are the 2 readings on a pulse oximeter because they are just the oxygen saturation percentage of blood and the pulse rate. These are very useful readings for monitoring oneself, especially when facing certain risks or conditions.
It is highly recommended to keep track of the readings and observe against the normal readings. This lets one know when to seek professional assistance.