A pulse oximeter is a small device that measures the amount of oxygen in your blood. It may clip onto the finger, toe, or earlobe. In our article below we’ll look more into what an oximeter is, how to use it properly and how to take a reading.
What is pulse oximetry?
Pulse oximetry measures the saturation of oxygen in your blood. It’s simple, non-invasive, and painless as a sensor is placed on your fingertip, toe, or earlobe.
There are some conditions that can affect your blood oxygen levels, including COPD, acute respiratory distress syndrome, asthma, collapsed lung, anaemia, congenital heart defects, heart disease, and pulmonary embolism.
Pulse oximetry can help to diagnose if there is a problem, as well as measure how badly the lungs are affected. It can also assess how well lung medication is working, evaluate how helpful a ventilator is, evaluate if someone momentarily stops breathing while asleep, and much more.
It can be done as a one-off measurement, or to monitor oxygen levels over a period of time.
How to use a pulse oximeter
If you are wearing nail polish of false nails, these can affect the reading. If possible, just take your polish or false nail off the finger you want to take the reading from, you don’t need to do them all.
Next, make sure you’re relaxed and sitting still. Shaking or shivering will affect the reading and may make it seem much lower than it should be.
Then, position the device on your finger, toe, or earlobe (depending on the device you have). Make sure the device fits securely, not too tight and not too loose. You also don’t want to force it on, so you might want to use your second toe as opposed to your big toe.
How to read a pulse oximeter
The oximeter will display a reading that is a percentage which is your blood oxygen saturation. It may also display your heart rate. For someone who is healthy, the reading should be between 95-100%. A normal resting heart rate reading is between 60 and 100 bpm.
For people with chronic conditions, you should discuss with your doctor what a good range is for you and what reading should prompt you to seek medical attention.
Additionally, if your pulse oximeter reading drops during exercise, it may be a sign of an underlying lung or heart condition, in which case you should speak with your GP as soon as possible.