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Oxygen therapy

Published: 25 Nov 2022
Updated: 4 Aug 2024
Next review date: 25 Nov 2028
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Oxygen therapy is used for reducing breathlessness in people who have low levels of oxygen in their blood. It can be given at home and in residential care settings. Here we explain how oxygen therapy can help, how you’ll be assessed and some of the risks associated with oxygen therapy.

What is oxygen therapy?

Oxygen therapy is a treatment for people who have a health condition which causes low levels of oxygen in the blood.
People receiving oxygen therapy are given air which contains added oxygen. Breathing in air with added oxygen increases the level of oxygen in the blood. This helps to reduce symptoms such as breathlessness and can make day-to-day activities easier to manage.
Illnesses that can cause low levels of oxygen in the blood include:
  • cancer
  • chronic obstructive pulmonary disease (COPD)
  • pulmonary fibrosis
  • heart failure
  • obesity-related hypoventilation
  • pulmonary hypertension
  • neurodegenerative conditions, such as motor neurone disease
  • cystic fibrosis (CF)
  • anaemia.

Do I need oxygen therapy?

A healthcare professional will assess you to see if you need oxygen therapy. The assessment may be done by your GP, respiratory consultant or a specialist nurse.
They will first make sure that you are being treated for any underlying conditions. They’ll also check that any reversible causes of breathlessness are being managed.
They may measure the level of oxygen in your blood using:
  • a non-invasive device that measures your oxygen levels – usually placed on your finger (a pulse oximeter)
  • a blood test.
If you’re found to have low levels of oxygen in the blood you may be prescribed oxygen.
Oxygen is not suitable for all people with breathlessness. If you’re breathless but you have normal oxygen levels, you should not be routinely started on oxygen therapy.
You might find it useful to try other measures to help relieve breathlessness, such as positioning, using a fan, breathing techniques and medication.

How is oxygen therapy prescribed?

Oxygen is prescribed by a doctor or specialist nurse. Try to think of oxygen as a drug and follow the prescription accurately. The doctor or specialist nurse will prescribe a flow rate of oxygen which is measured in litres per minute (L/min). They might also prescribe a target level of oxygen in the blood – known as an oxygen saturation percentage (SpO2). This would usually happen in a hospice setting for a specific need. Your doctor or nurse will prescribe the flow rate or saturation percentage for you.
The oxygen flow rate should not be increased outside the prescribed range without authorisation from a doctor or specialist nurse, even if you or someone involved in your care asks for it to be increased. Too much oxygen can be harmful and can cause further breathing problems.

How is oxygen therapy set up?

In your home

The doctor or specialist nurse will order the oxygen for you from a local oxygen supplier. The oxygen supplier will deliver it to you.
The specialist nurse will look at the risk of having oxygen in your home. They will also confirm that you’ve consented to home oxygen therapy.
An engineer will visit your home to install the equipment and carry out a risk assessment. They will also provide important information about safety and how to order oxygen refills.
The details of your oxygen prescription should be written in your care plan. Some home oxygen suppliers provide this information on a label on the back of the oxygen concentrator. The technician from the oxygen supplier will set the flow rate that has been prescribed for you.
If you have any questions about your oxygen prescription speak to a member of your healthcare team, such as your GP or specialist nurse. Or, you could contact your oxygen supplier. Some suppliers have a 24/7 helpline.

In a hospice or hospital

Some hospices and hospitals have piped oxygen. This means that oxygen is delivered to you through pipes that are attached to the wall, rather than a portable oxygen cylinder. Your doctor or nurse will explain to you how your oxygen therapy works where you’re being looked after.
If you need long-term oxygen therapy, you might be moved over to an air concentrator. This can give you oxygen in a safe and easily monitored way. Your healthcare team will give you the information you need before starting your oxygen therapy. If you have any questions or concerns, speak to your doctor or nurse.

How often oxygen therapy is given

You can use oxygen for short periods during the day to relieve breathlessness. For example, when doing certain activities.
It can also be used for longer periods during the day and night. This is known as long-term oxygen therapy (LTOT) – this is usually for at least 15 hours a day.
After the first few days, your doctor may check to see if the oxygen is making an improvement. If your breathlessness does not improve, your oxygen therapy will be stopped, and they’ll look at other ways to support you.

Oxygen therapy equipment

It can be useful to know about the different pieces of equipment involved in oxygen therapy, including the oxygen source and the delivery system.

Oxygen concentrators

An oxygen concentrator is an electronic device which takes room air and passes it through a filter. The filter removes nitrogen and other elements from the air, leaving a higher concentration of oxygen.
If you’re on long-term oxygen therapy, you’ll usually have a concentrator. This will be set up in a suitable room in the home. A portable concentrator can be carried around the home as well as outside. You might also have a back-up oxygen cylinder or a portable concentrator in case the concentrator stops working.

Oxygen cylinders

Oxygen can also be supplied in cylinders. These are metal containers containing oxygen at high pressure. They have an open and close valve to switch them on and off. They also have a flow rate regulator to adjust the flow rate of oxygen – this should be set at the prescribed flow rate.
Cylinders should be stored in a cool place. Storing the empty cylinders in a separate place from the unused cylinders can make it easier to know which have been used and which are still full. When an oxygen cylinder is not in use, it should always be turned off for safety reasons.
The choice between a concentrator and cylinder will be based on your individual needs. Generally, concentrators will be used if you need long-term oxygen therapy.

Nasal cannula and masks

Nasal cannula (small tubes that go inside your nose) are often used to deliver lower flow rates of oxygen.
Oxygen masks which cover the nose and mouth can be used as well. They can be useful for people who do not like nasal cannula. Or for people who need higher levels of oxygen. There are three types of face masks:
  • Simple face masks are usually used for symptom relief. They help support you with everyday activities or in an emergency situation. They do not give a specific percentage of oxygen.
  • Valved face masks are usually used if you have a long-term respiratory condition. They give an accurate percentage of oxygen to you. This is important because if you’re used to having a lower level of oxygen, having a higher level might cause problems. There are different coloured valves used for different percentages of oxygen.
  • Reservoir masks are usually used for high concentrations of oxygen. They have a bag attached to the mask which helps you to breathe in oxygen. They are usually only used for a short time.
Your doctor or nurse should ask you which type of cannula or mask you would prefer, and to try make this work with the flow rate of oxygen that’s been prescribed. Details about your mask or cannula should be written in your care plan.
Trans-tracheal devices for patients with a tracheostomy are rarely used at home and require care from a specialist team. If you have questions about this, speak to your doctor or nurse.

Other equipment

Trolleys and backpacks to carry portable oxygen sources can be provided if you move about. Ask your doctor or nurse about getting one if you need one.
Oxygen humidifiers are normally used if you’re receiving high flow rates of oxygen. They work by adding moisture to the oxygen being inhaled and can reduce discomfort. Humidifiers will also be used if you have a tracheostomy and are receiving trans-tracheal oxygen.

Risks of oxygen therapy

It’s important that you are aware of the significant safety risks involved with oxygen.

Fire safety

A high concentration of oxygen in the air increases the risk of fire. The specialist nurse will go through a form and ask you about things like smoking, fires, and who lives with you. They’ll do this when they order the oxygen. The oxygen supplier will also carry out a risk assessment in your home.
The Fire and Rescue service might visit your home to discuss fire safety, smoke alarms and safe exit routes in the event of a fire. You’ll normally be given written safety information. Home Safety Assessment details can be also found on local fire service websites.

Smoking

No one should ever smoke, vape or use electronic cigarettesli near you while you are using oxygen. This includes you, your family members, friends or others involved in your care.
You should always follow guidance on smoking from your healthcare team or the oxygen supplier. If you, or someone close to you smokes (including vaping and electronic cigarettes), they should smoke outside of the home away from the oxygen therapy. If this is not possible, the oxygen should be turned off for a period of time before smoking (including electronic cigarettes and vaping). Your healthcare team or oxygen supplier may have guidance on how long it needs to be turned off for.
Oxygen can remain on clothing and fabrics after it’s been used (this is known as ‘oxygen enrichment’). This can make them more flammable. Be careful about leaving your oxygen mask on fabrics – for example, taking your mask off to use the toilet, and placing it on the bed. If you’re not using the oxygen for a period of time, turn off the concentrator or cylinder.

Other fire risks

Oxygen sources should be kept at least six feet away from flames or heat sources such as gas cookers and heaters.
Oil-based emollients and petroleum jelly, such as Vaseline, can increase risk of fire in the presence of oxygen. They should not be used. Only use water-based products, for example KY Jelly or Aquagel on the hands and face or inside the nose while using oxygen. Speak to your pharmacist or healthcare team about what might be suitable for you.
Alcohol-based hand sanitiser can also cause a risk of fire around oxygen therapy. Wash your hands with soap and water instead if possible. If you use an alcohol hand sanitiser, let it evaporate before you touch anything.

Trips and falls

Oxygen equipment including tubing and electric cables can be a trip hazard in your home. Be aware of how the equipment will affect how you move around your home. This is especially important if you have sight loss or mobility difficulties.
If you have sight loss, ask your healthcare team or oxygen supplier about getting different coloured tubes. This might help you see the tubes more easily.

Skin care

Nasal cannula and oxygen masks can cause pressure damage if they are fitted too tightly. Check your skin around the ears, nose and cheeks regularly for discolouration and discomfort. If you need help to do this, ask your healthcare team or someone close to you to check your skin.
Discolouration might show as redness on lighter skin tones. In darker skin tones, you may see a change to a colour different from surrounding area (usually a darker colour).
If the mask or cannula are too tight, loosen the straps, or try repositioning the mask elastic below the ears.
You might be provided with foam wraps or gel pads from the oxygen supplier to make it more comfortable. Your healthcare team might be able to temporarily put gauze between the mask and your skin to make it more comfortable, too.
Cannula should be changed regularly – normally every month, or when blocked. Face masks should be washed and left to air-dry daily. You might like to alternate a few masks every 24 hours. Ask your healthcare team for support with this.
Oxygen can dry out your mouth, lips and nasal passages. Use moisturisers regularly to keep the skin in good condition. Remember to avoid petroleum jelly and oil-based products as they can increase the risk of fire.

If there’s a power cut

If you’re using an oxygen concentrator and there’s a power cut, try not to panic. Contact your doctor or nurse straight away. A healthcare professional should be able to help you connect to an alternative supply.

Financial help for oxygen therapy

If you’re using an oxygen concentrator, you might be entitled to some financial help.
Oxygen suppliers will give you a rebate based on how much oxygen and energy you’re using. The rebate is paid by the oxygen supplier, not your energy provider. The technician setting up your oxygen supply should tell you about the rebate when they set it up (see How is oxygen therapy set up? above).
You can find out more about oxygen concentrator rebates by contacting your oxygen supplier. We’ve listed some supplier’s websites below:
The free Marie Curie Support Line has Energy Support Officers who can help give information and support about energy bills. Call on 0800 090 2309 and ask to speak to an Energy Support Officer.

Information for carers, family and friends

There are different ways you can support someone if they’re having oxygen therapy. It’s always important to check with their healthcare team and get support from them when you need it.
Help the person get into a comfortable position – this will often be upright, but be guided by what’s comfortable for them. If they are breathless, they might find it comfortable to lean forward, supported by a cushion, as this can help give room for their lungs to expand.
Keep the person’s skin moisturised and offer them water regularly, as oxygen can dry out the mouth, lips and nose. Make sure to only used water-based products. Speak to the person’s healthcare team or a pharmacist if you’re unsure.
Make sure the person’s equipment is clean and comfortable. There may be pressure where the mask or cannula fits on their face.
Speak to the person’s healthcare team if you have questions about their prescription, or how the oxygen therapy works.
If you have any concerns about the oxygen therapy, call the person’s doctor or nurse as soon as possible. They will be able to check if the supply is working properly and resolve any issues.
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Published: 25 Nov 2022
Updated: 4 Aug 2024
Next review date: 25 Nov 2028
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This information is not intended to replace any advice from health or social care professionals. We suggest that you consult with a qualified professional about your individual circumstances. Read about how our information is created and can be used.

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