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Using a pulse oximeter to check you are OK
What is this pulse oximeter?
You have been given a machine because you have coronavirus. This machine is called a pulse oximeter.
The pulse oximeter tests:
How fast your heart is beating.
How well you are breathing. To do this it checks how much oxygen is in your blood.
Knowing these things means doctors can tell if you are:
This means you can get the treatment you need at the right time.
How to use this pulse oxximeter
Wash your hands before and after you use the pulse oximeter.
The pulse oximeter attaches to your finger and doesn’t hurt.
Make sure the finger you are going to use does not have any nail varnish or a false nail on it.
Make sure your hand is warm to the touch. Then rest it on your chest for five minutes.
Switch the pulse oximeter on.
Then attach the clip of the pulse oximeter to the finger next to your thumb, or your middle finger.
Watch the numbers on the pulse oximeter.
When the numbers on the pulse oximeter have stopped changing, write the numbers down in your coronavirus diary on page 22.
This is called taking a reading.
One number measures how fast your heart is beating.
One number measures how much oxygen is in your blood.
What to do with your information from the pulse oximeter
Write your readings in the your coronavirus diary section on page 22.
Please let your doctor know if writing is difficult for you or you find tables difficult. They will help you to record the readings a different way.
You need to write down your readings three times every day at the same time each day.
The times of day could be:
You should also test yourself if you begin to feel more unwell.
Write down how you feel in your diary.
For example:
Write down whether you are finding breathing easy or hard.
You should write your first reading in the blue area of your coronavirus diary on page 23.
If you have a thermometer you can take your temperature too.
It is a good idea to write down your temperature if you can.
When should I ask for medical help?
You need to go to your nearest Accident and Emergency (A&E) straight away or call 999 if any of these things happen:
You can’t finish a short sentence when you are resting because you are breathless.
For example: “I can’t finish this sentence.”
Your breathing suddenly gets much worse within an hour.
The blood oxygen number on the pulse oximeter stays at 92% or less.
Tell the person you speak to what the pulse oximeter says your blood oxygen number is.
You are coughing up blood.
You feel cold and sweaty with pale or blotchy skin.
You collapse or faint.
You develop a rash that does not fade when you roll a drinking glass over it.
You become restless, confused or very sleepy.
You have stopped peeing or are peeing much less than usual.
When you ring 999 tell the person you speak to that you might have coronavirus.
You can also tell them if you have a learning disability, you are autistic or both.
Contact NHS 111 or your GP if you have one or more of the following symptoms. Tell the person you speak to you might have coronavirus.
You slowly start feeling more unwell or more breathless.
You are finding it hard to breathe when you get up.
The pulse oximeter shows your blood oxygen level is 94 or 93 or keeps being lower than normal.
You feel like something is wrong.
That could be:
Feeling weaker than usual
Feeling very tired
Not wanting to eat
Peeing less than usual
You can’t do the things you normally can
Helping to keep you safe
It is important that someone checks on you regularly.
If you are staying away from other people in the same house as you, talking on your phone or through a doorway could be better than sending text messages.
This means they will be able to hear if you are getting more breathless or unwell.
If you live on your own, try and arrange to contact someone regularly.
Ask that person to ring you if you don’t contact them as planned.
Ask them to get help if you don’t answer.
If you are still unwell after three weeks, please contact your doctor.
When you have finished with the pulse oximeter
You will normally have the pulse oximeter for 14 days from the time you first became unwell with coronavirus.
After the 14 days return the pulse oximeter.
If you need to stay at home ask someone to return the pulse oximeter for you.
The pulse oximeter needs to be returned in the bag provided so that it can be cleaned before being given to someone else.
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Approval date: 12 May 2025
Review date: 12 May 2026
Version number: 1