What is the difference between continuous flow and pulse flow oxygen delivery?

Continuous Flow (CF) oxygen therapy can be administered at home, either using  cylinder oxygen, or by what is more commonly used today, a continuous flow unit. The units are generally designed for a stationary setting, although there is a small range of portable continuous flow units now available on the market.

The CF machine constantly emits oxygen, irrespective of whether the user is inhaling or exhaling. In contrast, portable oxygen concentrators (POCs) only discharge oxygen on inhalation, thus reducing the total amount of oxygen required to produce, which assists the user to meet their required oxygen levels. Furthermore, the POC provides a ‘pulse’ of oxygen every time you inhale and has conveniently been downsized on the basis of providing oxygen ‘on demand’. 

As POCs are relatively lightweight, they are very easy to move about and several are approved for travel on Australian airlines. They provide a fantastic alternative oxygen source and allow a much more active and varied lifestyle for anyone needing oxygen therapy.

When considering your options for oxygen therapy, it's important to consider your oxygen needs, your lifestyle and then how best to have both met. You should also seek advice from your respiratory specialist or doctor. If you are a low user of supplemental oxygen, you will have more choices and may find all your oxygen needs can be provided by just one POC. Other individuals may need to look at combining a continuous flow machine with a POC unit, to allow them to get out and about more often.

Continuous flowPulse flow oxygen