When is a referral made and how is home oxygen therapy assessed?

On this page, we explain how someone is referred for home oxygen therapy, and how you are assessed.

When could I be referred for home oxygen therapy?

If you’ve been diagnosed with a lung condition, have the right medication, but still feel very out of breath - it may be time for your health care professional to investigate if your blood oxygen levels are low.

You can be referred for assessment by:

  • your GP or practice nurse
  • community services such as the community respiratory team, community matron, physiotherapist or occupational therapist
  • your hospital doctor - if you have been in hospital after a flare-up of your condition, or you are newly diagnosed with a lung condition
  • an occupational health department if you work
  • a private health care provider.

Before you are referred for assessment, you’ll have simple test, called pulse oximetry, to make sure that an assessment for oxygen is right for you. If your oxygen levels fall below a certain percentage, and your health care professional thinks oxygen therapy could help, you may be referred to the home oxygen assessment and review service.

Palliative oxygen

If you are approaching end of life and your advanced condition is causing both low oxygen levels and severe breathlessness, oxygen may be considered by your palliative care team. This may be for your use at home or in a hospice or nursing home. At this stage, oxygen can help relieve any distress that can occur when breathing is difficult. Patients with an advanced condition who are very breathless, but do not have a low blood oxygen level do not find oxygen therapy helpful. There are other treatments in this situation which work much more effectively. Read more about managing breathlessness.

Oxygen treatment for advanced conditions is only be considered once other options to help ease distressing breathlessness have been tried. A simple handheld fan can be very effective at helping to alleviate the sensation of breathlessness. Oxygen equipment can be bulky, heavy and take up space in the home. It can also make it harder to talk with loved ones, or eat, so palliative oxygen treatment should be carefully planned and may not always be helpful. Read more about end of life care.

How will I be assessed for home oxygen therapy?

Once you are referred, the oxygen assessment must be done by an oxygen specialist. This can happen in a variety of places. You can sometimes be assessed in an outpatient clinic at the hospital. You may be assessed at home if your condition is very severe and this service is available in your area.

You will be asked about your smoking habits at your oxygen assessment and, if you smoke, offered help and support to quit. Current guidelines highlight safety concerns about smoking while using home oxygen therapy, because of a number of very serious (even fatal) incidents. Therefore, it is not recommended that home oxygen therapy is prescribed to current smokers until they have gone through a program of treatment and support to quit. Often smokers with low oxygen levels find that their oxygen levels recover, and they no longer need home oxygen once they have quit. This is because a toxic gas called carbon monoxide in cigarettes soaks up oxygen in the blood meaning less is available for the vital organs in the body.

What tests will I have?

Pulse oximetry

If you have not already had a pulse oximetry test, this will be done first to make sure you are suitable for the assessment. Read more about pulse oximetry and what this test involves.

Blood tests

You will have blood tests to measure how well your lungs can provide oxygen to your body.

A blood sample will be taken from your wrist or from your ear lobe. The blood sample will be analysed, and the results will determine how much oxygen you have in your blood. You may then be asked to breathe oxygen through a mask, or through some tubing in your nose, for at least 30 minutes before a second blood sample is taken.

The blood sample will help to determine if the oxygen therapy has helped to correct your blood oxygen levels by the right amount. Some people with respiratory conditions can be sensitive to additional oxygen therapy being given to them, in some cases too much oxygen therapy can lead to the body retaining carbon dioxide. Too much carbon dioxide can lead to drowsiness, morning headaches/heaviness, lack of concentration and can be very serious. It’s very important you are prescribed the accurate amount of oxygen therapy to correct your blood oxygen levels without causing a significant change in your carbon dioxide levels. If this does occur, home oxygen therapy may not be suitable for you and other options would be discussed with you with a specialist.

In some cases, you may need a second appointment four to six weeks later for a second blood test. This is to check that you have consistently low levels of oxygen in your blood before a decision is made. If the blood tests show you have too much carbon dioxide in your blood, you may need to see a specialist to review your condition before you are assessed again.

Exercise or walking tests

You may also be asked to take an exercise or walking test. This assesses your oxygen needs and if your blood oxygen levels only fall when you’re active. You may be asked to walk for six minutes up and down an indoor corridor or to climb a few stairs. If you need to, you can stop and rest.

Once the test results have been reviewed, you will be told if oxygen therapy is right for you. If the walking test shows your oxygen levels drop below a certain level, you will be asked to repeat the walking test using oxygen. This will involve you carrying the oxygen equipment or using a trolley as you would if you were outdoors doing your usual activities. Your home oxygen specialist can discuss the different types of oxygen equipment available and help determine what will suit your needs.

What happens if I need home oxygen therapy?

You will be assessed by a health care professional who will be able to prescribe the right amount of oxygen for you. This may be your nurse, a physiotherapist or an occupational therapist. They will know the equipment provided by the local oxygen supplier. You will be advised who your first point of contact is for oxygen-related questions.

If you are told you need home oxygen therapy, you’ll be assessed to make sure you get the right amount of oxygen for you. Not everyone needs the same amount!

Make sure to ask your health professional to explain what your personal target saturation range is, for example 88-92%. This maybe a higher range or a lower range depending on your own condition.

The amount of oxygen (flow) you are prescribed will help keep you within your personal range. It’s important to only use your oxygen as prescribed especially not to increase the flow rate on your equipment. You should be monitored regularly so your prescribed flow rate can be adjusted according to your needs.

If you’re told you need home oxygen therapy, it’s important you understand why and what will happen next. Don’t be afraid to ask questions. You should know how the service will work, how many hours a day you should use your oxygen, how often you’ll be assessed, and which delivery method is best for you.

If you’re told you need oxygen therapy:

  • You should be given an explanation of what happens next and the choices you have.
  • You should be given information and training about using oxygen in a language you and your family or carers understand.
  • You should be shown the different types of equipment and try them out to see which is best for you. Ask your health care professional to explain which delivery method is best for you and why. Your prescription can be changed later if you need a different oxygen therapy.
  • You might be asked if you need help with daily living from your local health care team or social services. If you do need help, someone will come to see you at home.
  • Your GP will be told the result of your assessment and that you have been prescribed oxygen.
  • If you smoke, you will be offered support and treatment to quit.

How often will my home oxygen therapy be reviewed?

Clinical guidelines for oxygen assessment and review of specific lung conditions will vary. Depending upon the nature and stability of your condition, your home oxygen therapy may be reassessed every three to six months. Your oxygen therapy should be reviewed at least once a year.

If you have a respiratory tract infection or a flare-up, your health care professional will usually review your oxygen therapy promptly and you may need to be hospitalised. If your oxygen was adjusted following a flare-up or lung infection, you may be reviewed again within eight weeks to see if any more adjustment is needed.

If you experience new symptoms such as a morning headache, or you can’t think straight and are drowsier or sleepier, tell your health care professional. You might have too much carbon dioxide in your blood.


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