Oxygen Therapy

The Benefits and Basics of Home Oxygen Therapy

Oxygen is a gas found in the air we breathe—and it is necessary for human life. People with chronic obstructive pulmonary disease (COPD) may have difficulty getting enough oxygen into their lungs.

This is not because the air is any different for them—rather, it’s because their lungs don’t work as well to extract the oxygen their body needs. To address this, oxygen therapy (also called supplemental oxygen) may be prescribed, just as a medication would be, for some people with COPD.

Oxygen prescriptions are required when people’s oxygen saturation (the amount of oxygen in the blood) becomes too low. Oxygen therapy “tops up” the air you breathe with higher amount of oxygen so more can get into the body and prevent the life-threatening effects of low oxygen.

Some people with COPD need oxygen therapy all the time while others need it only sometimes.

How does it look like?

Living with Oxygen
<div class="title">Living with Oxygen</div>

When is oxygen therapy needed?

Doctors use several indicators to decide whether people with COPD need oxygen therapy. In the office, doctors first examine how a person is breathing—how much effort is needed, if they are comfortable at rest, and how easily they can breathe while moving around. They look for signs such as a bluish discoloration of the lips or fingers. Blood oxygen levels are measured by a pulse oximeter device attached onto a finger.


People requiring home oxygen may also need an arterial blood gas test (ABG test). It only takes a few minutes and is often taken from an artery inside the wrist. If the value is below a certain level, it generally means supplemental oxygen is needed.


Some people only need oxygen during specific activities (e.g., exercising or sleeping) or for short periods of time (e.g., after a COPD flare-up), while others need oxygen continuously.

Starting oxygen therapy

Your doctor will write you a prescription to begin oxygen therapy, which will include:

• How to use it
• How often to use it
• The flow rate (the level of oxygen of oxygen per minute—e.g., 1 L/min)


When discussing oxygen therapy with your doctor, tell them about any other prescription medications you take. Oxygen therapy will most likely be used in addition to your other medications; it is not a replacement for them. If you don’t think the oxygen therapy is working for you, see your healthcare provider before making any changes.


The provider of your oxygen therapy (e.g., a private homecare company or a provincial provider) will then come to your home to deliver and set up the oxygen system. They will also provide education and directions on how to use it. It is important to follow all of the specific instructions for safe use of oxygen therapy.

Symptoms of low oxygen

COPD restricts the flow of air into and out of the lungs. It can lead to hypoxemia (low oxygen levels in the blood) and hypoxia (low oxygen levels in the body’s tissues).

• Symptoms of low oxygen include:
• Shortness of breath at rest
• Shortness of breath with activity
• Shortness of breath when waking up
• Headaches
• Confusion
• Bluish discoloration of the lips, fingers, or nails (cyanosis)
• Swelling in the lower legs (edema)

By using supplemental oxygen, people with COPD can often lessen their feelings of shortness of breath both at rest and with exercise. People with COPD may be able to live more comfortably with added oxygen.

How is oxygen therapy different from other therapies?

There are various medical device systems available for patient use—the right one for you will depend on your condition and symptoms.

Oxygen therapy is prescribed when the oxygen levels in the blood are too low, and it helps maintain safe levels of oxygen in the body.

Oxygen therapy is commonly delivered via small silicon tubes in the nostrils called nasal cannulas.

Although it can help with feeling less out of breath, oxygen therapy alone will not help with mucus and coughing.

Bilevel Positive Airway Pressure (BPAP) is especially helpful for people with COPD who have high levels of carbon dioxide in the blood because the air they need to breathe out gets trapped in the lungs.

BPAP therapy pushes a high pressure of air into the lungs to inflate them to their maximum potential, similar to blowing up a balloon. It then switches to a lower pressure to help push trapped air out of the lungs. This increases the amount of oxygen available and forces out trapped carbon dioxide.

BiPAP is more cumbersome than oxygen therapy with nasal cannulas as it requires a sealed mask around the mouth and/or nose.

Humidified high-flow therapy (HHFT) is usually prescribed for patients who tend to struggle with cough and excess mucus. This therapy hydrates the airways—which can’t be done as effectively with BPAP or oxygen therapy. It also provides a little bit of pressure to open the airways.

Patients often describe the therapy as more comfortable than BPAP because it doesn’t require a sealed mask on the face, just nasal cannulas. Because of this, you can eat, drink, and talk while using it. It can be used anytime, whether you’re awake or asleep, and it is portable.

Types of oxygen therapies

Oxygen is delivered via silicone nasal tubes (also called nasal cannulas) or a face mask. The oxygen can come from different types of equipment, such as: Oxygen concentrators, Portable oxygen concentrators (battery operated), Oxygen cylinders and Liquid oxygen.

Oxygen concentrator

An oxygen concentrator is the most common device used at home by people with COPD for delivering oxygen—95% of Canadians on oxygen use concentrators in their homes. It takes oxygen from the room’s ambient air, concentrates it, and removes other naturally occurring gases before pumping the oxygen back out.

Oxygen concentrators are bulky, can be loud and less portable than other types of oxygen therapy, but they are less expensive and don’t require filling. The machines can have a 50-foot tubing attached to them, allowing users to move around their homes freely.

(Helpful hint: To avoid tripping over the oxygen tank or tubing, some people tape the tube to the back of their shirt.)

Portable oxygen concentrator (POC)

Portable oxygen concentrators, or POCs, are similar to oxygen concentrators in that they concentrate the oxygen in ambient air. Unlike an oxygen concentrator, however, POCs are portable and are usually small and battery operated.

The main advantage of using a POC is that it allows users to easily walk around and be more active. The downside is that they often deliver only a certain level of oxygen (for example, up to 2 litres of oxygen per minute, although there are a few POCs that can deliver 5 litres per minute). This means that POCs may not be an option for people requiring higher rates of flow—portable liquid 02 may be a better option, as discussed below.


Also, because they are battery operated, they will usually only operate for a maximum of two hours, depending on the flow.

Oxygen cylinder

Compressed oxygen gas is stored in cylinders that come in various sizes and weights. Smaller oxygen tanks can be transported and used outside of the home while larger ones may be stored at home as backups in case of a power outage or if a concentrator breaks down. To make the oxygen supply last longer, smaller tanks might be used along with oxygen-conserving devices


Of note, O2 cylinders should never be used during sleep since there are no alarms on the cylinder to warn if the oxygen runs out. Instead, it is advised people remain on their concentrator overnight if oxygen is required for sleep.

Liquid oxygen tank

Liquid oxygen tanks store oxygen in a liquid state so they can hold a much higher volume of oxygen than traditional cylinders. Liquid oxygen systems include a large stationary tank and portable liquid tanks that fill from the larger stationary tank. A portable liquid tank lasts much longer and can deliver higher flows than a portable oxygen concentrator, making it helpful for people who are very active or require high levels of oxygen.

However, liquid gas evaporates if it isn’t used in a timely manner. Fortunately, these tanks are refillable and convenient, as liquid oxygen and oxygen gas are available for home delivery. These tanks may be a bit more difficult to use in the beginning, but their high flow rates and portability make them a great option for many users.

Want to know more? This video explains the components of a liquid oxygen system and how to use and care for your device.

In addition to oxygen,

here are other therapies to help with breathing that you should know about — learn more here.


Frequently Asked Questions

It depends. The worse your hypoxemia (low amount of oxygen in your blood), typically the more oxygen you’ll need. Everyone is different, but on average, people with severe COPD need oxygen for at least 16 hours per day—and usually all day long.

Funding is available in Canada for most people who require long-term oxygen therapy. Here are the provincial guidelines to help you determine whether you qualify for funding.

Consult your COPD action plan. If you have a pulse oximeter at home, you can use it to determine your current oxygen level and follow any instructions to increase your oxygen based on your action plan. Never adjust your flow without consulting your provider first.

Yes, too much oxygen can be just as dangerous as too little. Using more oxygen than prescribed can lead to oxygen toxicity as well as a buildup of too much carbon dioxide in the body. Symptoms can include delirium, muscle twitching in the face and hands, chest tightness, difficulty breathing, coughing, dizziness, blurred vision, and nausea. Oxygen toxicity can be fatal.

Yes, oxygen therapy is safe as long as you follow your doctor’s instructions. Do not use recreational drugs or alcohol while using oxygen therapy, as they can slow your breathing.

Yes, but you can manage that risk by taking some safety precautions.

Never smoke while using oxygen or near someone using oxygen.
• Don’t operate oxygen tanks around open flames and heaters.
• Install extra fire alarms throughout your home.
• Keep oxygen away from the stove, oven, and any grease while cooking.
• Do not store oxygen in a tight space, such as a small closet.
• Do not use aerosols such (e.g., hair sprays or deodorants) near oxygen equipment.
• Never use grease or an oil-based lubricant near oxygen.