Pulse Dose vs. Continuous Flow: The Difference
Pulse dose (PD) oxygen delivery is based on breathing and inhaling, which customizes your oxygen delivery to your breath rate.

Continuous flow (CF), on the other hand, delivers oxygen at a constant adjustable rate, indiscriminate of the user’s breathing, measured in liters per minute.

Pulse does output is determined by the size of the individual pulse (called a bolus) and is measured in milliliters per breath, rather than liters per minute.

Much of the oxygen in continuous flow unit may be wasted simply because we exhale and pause between breaths. Pulse units are designed to produce a pulse when it senses when you are inhaling or taking a breath.

For a continuous flow portable oxygen concentrator, think of it like a water fountain: If an individual stands in front of a water fountain flowing at 1 liter per minute, they don’t actually drink one full liter of water. The amount of water a person drinks is determined by the number of sips and the size of the sip. The rest of the water is wasted. The same applies to continuous flow oxygen; the net amount of oxygen inhaled is a combination of the flow rate, the number of breaths and the size of the breaths.

Pulse dose oxygen is more sophisticated. Pulse dose mechanisms are more sensitive, utilizing an oxygen conserver and other technology to deliver oxygen to the patient based on breathing rate and other factors. The sensor determines when the patient begins inhaling and delivers the oxygen pulse/bolus at that moment. Pulse dosing is more akin to a glass of water with a straw than a fountain; the intake will be based purely on the amount and intensity of sips. When an oxygen concentrator is said to be a “single-solution” for on-the-go, at home and during sleep, it usually employs pulse dose oxygen technology so that it can deliver the proper amount of oxygen during all phases of daily activity and during rest.

When it is time to choose the right oxygen concentrator for you, talk to your doctor about whether pulse dosing or continuous flow oxygen delivery is better for your needs. Based on this difference between pulse dose vs. continuous flow oxygen, it is also important to consider how you would like to use the oxygen: on the go, at home or just for sleep. Pulse dose oxygen concentrators seem to be preferable for doing a number of different things, but continuous flow portable oxygen concentrators may be a sufficient option, particularly if breathing will remain relatively constant.

Generally you're not encouraged to use a POC for sleep, mostly because of the shallow breathing and uncertainty of being able to trigger the pulse dose on every breath. To determine whether you're getting enough 02 to keep yourself saturated, you should use a pulse oximeter and measure your 02 until you figure out what settings are appropriate for what activities. It may vary for different POCs, so be sure to know what settings you need for what activities on your own machine.

I still use tanks. Many strangers ask about the "nice machines" for O2 and I have to explain this repeatedly. I'm glad they care enough to ask.

The Group consensus seems that the pulse dose settings are likely adequate for sedentary activities and challenging for more intense movement and higher breathing rates. We always have to prepare ourselves with the stronger breathing techniques in advance.

Alice Rose, I'd suggest that your experience is primarily what many of us find: the POCs don't produce anough 02 to keep us adequately saturated when we're doing more than just sitting. I use my POC for flying and traveling. I can't exercise with it because it doesn't produce enough to keep me saturated. If I have schlep all my luggage myself, it won't keep me adequatey saturated. I have the Inogen G5, which produces the most 02 at 1.26 LPM. POCs just don't produce enough 02 for many of us to use them for everything.

I agree with Jean on this. I use my constant flow when I'm at home . I only use the pulse concentrator when I go out which is rarely because I get very winded when I move around . I hope everyone is doing as good as can be expected, have a great evening and bless you all.