20 Apr 2021

Pulse Oximeters

What are they and what are they used for?

Pulse oximetry is a non-invasive test that measures the levels of oxygen in your blood – a small clip like device called a pulse oximeter measure the oxygen levels in the blood. The device is most commonly attached to a fingertip, but can also be attached to a toe or earlobe.

What is the purpose of a pulse oximeter?

A person’s blood oxygen level is an indicator of how well the body distributes oxygen from the lungs to the cells, and it can be important for people’s health. Oxygen is carried by red blood cells, collecting oxygen from the lungs and delivering it to all parts of the body. The purpose of an oximeter is to check how efficiently your heart is pumping oxygen through your body.

How it works

A pulse oximetry reading is a painless process. The device is usually placed on a fingertip where tiny beams of light pass through the blood in the finger, measuring the amount of oxygen saturation.

The pulse oximeter will then be able to tell you your oxygen saturation levels as well as your heart rate.

The device works better with warmer hands and because oxygen levels can fluctuate, consider taking measurements a few times a day.

Oximeter Readings

Most healthy people will get an oxygen reading of 95% or above. Some people with existing health conditions may have a lower normal reading so follow your GPs advice. Here is some general guidance on Oximeter readings below 94%.

If you get a reading below 94% you will be asked to repeat the test again in 15 minutes. Make sure for the repeat test that you follow the instructions for using the pulse oximeter carefully - i.e. that it is positioned correctly, that you have been at rest for at least five minutes. If your repeat test result is 95% or above then it is possible that your initial result was due to a variety of factors including positioning of the oximeter, whether you were sitting or lying, your level of exertion, etc. If your repeat test result is below 95% you need to take action. If your repeat test result is below 93% this is a sign that you may need extra support. For example you might need to go to hospital or receive supplemental oxygen. Contact your GP or out-of-hours service by telephone straight away and advise them of your oxygen saturation reading.

If your repeat test result stays around 93% or 94% this is a sign your breathing may be getting worse. Continue to monitor. If your oxygen saturation stays below 95% for longer than two hours contact your GP or out-of-hours service by telephone straight away and advise them of your oxygen saturation reading. In an emergency - for example if you are having severe difficulties in breathing - please contact 999 or 112.

When blood oxygen level is too low compared to the average level of a healthy person it means the body is having difficulty delivering oxygen to all of its cells, tissues, and organs and can be a sign of a condition known as hypoxemia.

The pulse oximeter also shows your heart rate. A normal resting heart rate for adults ranges from about 60 to 100 beats per minute (athletes with a higher cardiovascular fitness will usually have a lower pulse).

Why might someone need an oximeter?

A pulse oximeter can be a useful device for the home if you or a family member have an underlying illness such as diabetes, heart disease, lung disease or a respiratory condition so you can monitor oxygen levels at home and share the readings with your doctor.

Pulse Oximeters are available from your local Hickey’s Pharmacy – don’t hesitate to ask a member of our team for advice on how it may be of assistance.

Breathlessness is also an important measure of how severe your symptoms are. If your breathing is getting much more difficult, you need to take action. Telephone your GP, GP out-of-hours service or in an emergency call 999 or 112.

If you experience a sudden change in any of your other symptoms please telephone your GP, GP out-of-hours service or in an emergency call 999 or 112.