Oxygen Therapy - Treating Your Condition: Smoking Cessation

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Oxygen therapy

Oxygen therapy counters one of the main problems of lung disease — lack of oxygen in the blood. As COPD becomes more severe, the oxygen level in your blood may become dangerously low, preventing vital organs and tissues from getting enough oxygen. In some people, oxygen falls during exercise or sleep, but is otherwise normal. In other people, the oxygen level is also low at other times, even when they are not active. If your oxygen level drops too low, you may need oxygen therapy in addition to medicine to help you breathe and prevent complications.

In COPD patients with low oxygen levels, oxygen therapy is the only treatment that has been proved to prolong life. Large studies have shown that when used for more than 15 hours a day, it increases survival by about 30%. It can also help you feel more alert and physically stronger.

There are different types of oxygen delivery systems. Some are large and stationary for use while you lie in bed or sit in one place for an extended period. Others are small and lightweight enough to be used while going out or even exercising. Which delivery system you use will depend on many factors, including how active you are and whether you need oxygen therapy all the time or just for certain periods.

Continuous or intermittent oxygen therapy?

Some people need oxygen therapy continuously, or nearly continuously, whereas others need it only occasionally, when their oxygen falls below an acceptable level. You are considered a candidate for continuous oxygen therapy if your oxygen level is low even when you are at rest. Continuous oxygen therapy doesn't improve survival in patients who don't meet this criterion.

If you need continuous oxygen therapy, you may not need it indefinitely, particularly if you started using it when you were having an acute exacerbation. About 40% of patients improve enough after a month to cut back on the amount of time they use supplemental oxygen. Many of these patients need to resume continuous therapy again at some point. If you've been on continuous oxygen therapy and then stop it, you and your doctor should monitor your symptoms and oxygen level regularly to see if you need the therapy again.

If you don't need continuous oxygen therapy, intermittent therapy can be helpful on a temporary or short-term basis if your oxygen level drops in particular circumstances, such as when you are having an acute exacerbation, when you exercise, when you sleep, or when you are on an airplane. Intermittent oxygen therapy hasn't been shown to extend survival, but it can help you feel better and give you more stamina.

Choosing an oxygen system

Devices for oxygen therapy can be stationary or mobile. Unless you are confined to bed, you will probably want to use a mobile system at least some of the time. A mobile, or portable, oxygen system allows you to move from room to room and go out of your home. Some mobile units can be worn around the waist as fanny packs, making them especially convenient during exercise. If you use oxygen at night, you might consider having a stationary unit for use in bed and a mobile one for daytime use.

Oxygen is usually inhaled through a nasal cannula, a plastic tube with prongs that fit into the nostrils. In the standard oxygen delivery system, oxygen flows continuously into the nose, even if you are not inhaling. But some systems come with an attachment called an electronic demand device, which senses when you are inhaling and delivers oxygen only at that time. This conserves oxygen.

If you can't use a nasal cannula or if you are bothered by its appearance, you can have the oxygen fed directly into your windpipe. This is called transtracheal oxygen therapy. Although this method requires a procedure to make an opening in your neck that leads to your trachea, some people prefer it to a nasal cannula because they can hide it with a scarf or collar. Transtracheal oxygen delivery is also used by seriously ill patients who need more oxygen than can be effectively delivered through the nose.

Following are descriptions of the different oxygen delivery systems.

Oxygen concentrator. This oxygen system is a relatively large electrical machine that draws oxygen from the air. This is the least expensive of all oxygen delivery systems because you don't have to buy canisters of oxygen; rather, the machine concentrates the oxygen from air in the room. The disadvantage is that they limit your ability to get around. Although some units can be wheeled around on casters, with most of them your mobility is limited by the length of the tubing. An oxygen concentrator is a good choice for use in bed or while sitting in your favorite chair.

Compressed gas or liquid cylinders. These are bottles of oxygen in either gas or liquid form. The cylinders come in different sizes: Some are large stationary units, and others are small and portable. Liquid oxygen is the most portable and lightweight delivery system. The lightest liquid oxygen cylinders weigh just 6.5 pounds and last for four hours. Some portable liquid oxygen cylinders can be worn easily, making them ideal for use during exercise. Compressed gas cylinders need to be replaced when they run out, and liquid cylinders have to be refilled. A cylinder of liquid oxygen lasts four times longer than compressed gas of the same weight, but liquid oxygen is more expensive. Medical insurance usually covers the cost of oxygen delivery systems, as long as you meet the criteria for needing supplemental oxygen.

Last updated:	May 23, 2007