There has been a lot of discussion in the media about pulse oximeters and the potential for them to save lives. This article looks at how a pulse oximeter works, why these devices can be useful and how to interpret the readings from your pulse oximeter.
What is a pulse oximeter?
A pulse oximeter is a lightweight sensor that is placed on the fingertip to measure how much oxygen the haemoglobin in your blood is carrying. It is a non-invasive device meaning that it is pain free and relatively easy to use in the house.
The oximeter passes bright light through the blood vessels in the tip of the finger to a light detecting sensor on the opposite side and measures the changes in light absorption to determine the oxygen concentrations of the blood.
The measurement taken is known as oxygen saturation and is expressed as a percentage out of 100. A second reading is simultaneously given, and this is your heart rate (or pulse) expressed in beats per minute.
What does oxygen saturation level mean?
Oxygen is carried around the body by haemoglobin found in red blood cells, oxygen saturation is a measurement of how effectively the oxygen you inhale is being exchanged between your lungs and blood and how efficiently this is being transported around the body.
Higher readings demonstrate that the body is exchanging and transporting oxygen efficiently whereas lower or falling readings (sometimes referred to as hypoxia) can be an indicator of underlying disease and should be investigated further.
Why should I measure my oxygen saturation levels at home?
Individuals with underlying lung conditions such as pneumonia, lung cancer, COPD & asthma may benefit from monitoring oxygen saturation levels at home. Oxygen levels can drop significantly before an individual starts to experience symptoms (silent hypoxia), noticing reductions in oxygen saturation early can help identify opportunities for treatment.
Monitoring these levels can also help clinicians decide whether someone can be treated at home or when hospitalisation may be required.
How to take an oxygen saturation reading
Before taking a reading it is important to thoroughly wash your hands, ensure the finger you are going to attach the sensor to does not have any nail polish or false nails.
Use the following steps to improve the accuracy of your reading:
- Ensure your hand is warm, this promotes blood flow to the area and helps to take a clear reading
- Allow your hand to rest on your chest for a period of around 5 mins.
- Turn on your pulse oximeter.
- Attach your pulse oximeter – for best results use your index or middle finger.
- Wait for the numbers on screen to stop changing before noting the figures shown on screen.
- Jot down additional information such as the time of day the reading was taken, how you are feeling/ any symptoms you are experiencing
When should I contact my GP about my oxygen saturation levels?
An oxygen saturation level of between 95-100% is generally considered within normal limits however this can be lower in individuals with COPD, and it is important to know what is normal for you. A drop in oxygen saturation of 3% even if this remains within the normal window can be a sign that something has changed and is worth discussing with your GP.
Readings of 92% or below should be treated as urgent and your GP contacted immediately.
Choosing the Right Pulse Oximeter for you
Here at Right Medicine Pharmacy we stock the Medicare Lifesense Digital Pulse Oximeter, this oximeter is lightweight, easy to use and provides accurate results in as little as 10 seconds!
This model is packed with additional features such as; visual heartbeat display, alarm function for low oxygen saturation and high/low pulse and automatic power off to keep power consumption low.
Even better we are currently offering 20% off!