Understanding Pulse Flow Settings: Does 1 - 5 Equal 1LPM to 5LPM?

Quick Answer

No, the pulse flow settings of 1-5 do not mean 1LPM to 5LPM. Pulse flow and continuous flow are different oxygen delivery methods that cannot be directly equated. Pulse flow delivers intermittent bursts of oxygen only during inhalation, while continuous flow provides a steady stream of oxygen measured in liters per minute (LPM). The numbers on pulse flow settings indicate relative oxygen output per breath, but this varies by device and does not correspond to a constant flow rate over time like LPM.

While there are theoretical equivalence calculations based on breathing patterns, in practice, pulse flow oxygen delivery can differ from these estimates. Consult with your healthcare provider to determine the appropriate pulse flow setting for your individual needs.


If you use an oxygen machine, you've seen settings labeled 1 to 5. You might wonder if these numbers are the same as liters per minute, which measures oxygen flow. They're not, but don't worry-it sounds complicated, but it's actually pretty simple. We're going to explain what those settings on your oxygen device mean and how to use them right. By the end of this article, you'll have a clear understanding that will help you feel more confident about your oxygen therapy. So let's break down these settings together and make sure you're getting the most out of your device.

1. What Is Oxygen Therapy?

Oxygen therapy is simply a treatment that gives you extra oxygen. It's usually needed when health conditions make it hard to absorb enough oxygen from the air naturally. This extra oxygen can help people with lung diseases like COPD, asthma, or heart problems to breathe better and feel less tired.

There are two methods to deliver this oxygen: continuous flow and pulse flow.

Continuous Flow

With continuous flow, oxygen comes out of the machine at an even rate all the time. It doesn't stop or change whether you're breathing in, holding your breath, or breathing out. You get a fixed amount of oxygen per minute, which can be adjusted depending on what your doctor recommends.

Pulse Flow

Pulse flow works differently. The oxygen machine only releases oxygen when you inhale. This means if you're not taking a breath, the machine isn't putting out oxygen. It's designed to work with your breathing pattern and can adjust to how often and how deeply you breathe. Because it's not constantly running, this mode can minimize the size and extend the battery life of portable oxygen concentrators.

Both continuous and pulse flow methods aim to give you the right amount of oxygen, but they do so in different ways. Continuous flow ensures a constant supply, while pulse flow tries to match your natural breathing rhythm, delivering oxygen only when you need it.

Understanding these two delivery systems is crucial because it affects how you use your oxygen therapy device and how effective the treatment will be for your individual needs.

2. How Are Pulse Flow Settings Defined?

Understanding pulse flow settings is key to using a portable oxygen concentrator effectively. These settings are different from what you might expect if you're familiar with liters per minute (LPM).

Clarification on Pulse Flow Settings

Pulse flow settings control how much oxygen you receive with each breath you take. Instead of a continuous stream, these settings deliver oxygen in bursts that coincide with your inhalation. The machine detects when you start to inhale and releases a predetermined amount of oxygen.

Distinction Between Pulse Flow Settings and LPM

LPM is a measure used for continuous oxygen flow, where the oxygen is provided at a constant rate every minute. Pulse flow, on the other hand, doesn't have a standard flow rate over time because it's not continuous-it sends oxygen only during inhalation. So, the numbers on pulse flow settings don't correspond directly to liters per minute as they do with continuous flow.

Misconceptions About Pulse Flow Settings Equating to LPM

There's a common misunderstanding that a setting of 1 to 5 on a pulse flow machine means you're getting 1 to 5 liters per minute of oxygen, similar to continuous flow settings. That's not accurate. The numbers on pulse flow machines are simply settings, not exact measurements of volume like LPM. They represent relative output levels that can vary based on the manufacturer and the specific device.

3. Why Don't Pulse Flow Settings Equal Liters Per Minute?

Understanding why pulse flow settings don't equal liters per minute (LPM) requires a look at how oxygen is delivered differently in each mode.

Explanation of Intermittent Delivery in Pulse Flow

Pulse flow delivers oxygen intermittently, meaning that it only provides oxygen when you inhale. As you begin to take a breath, a sensor activates the machine to release a burst of oxygen. Since these bursts are synchronized with your breathing, they're not constant and therefore don't add up to a steady rate over a minute.

Differences in Measurement Units for Pulse Flow and Continuous Flow

The measurement units for pulse flow and continuous flow reflect their delivery methods. Continuous flow is measured in LPM because it's a continuous stream of oxygen-so if you set it to 2 LPM, you know you're getting 2 liters of oxygen every minute. Pulse flow doesn't work like that. Instead of a volume per minute, the settings correspond to the size of individual oxygen bursts provided with each breath. So, a setting does not equate to a fixed volume of oxygen over time as LPM does.

This distinction means that while continuous flow can be quantified easily over any given period, pulse flow cannot be directly compared to LPM since it isn't a measure of volume over time but rather a measure of volume per breath.

4. Where Does the Equivalence Between Pulse Flow and Continuous Flow Come From?

When discussing oxygen therapy, sometimes you'll hear terms suggesting that pulse flow settings are equivalent to certain continuous flow rates. This idea of "equivalence" stems from an attempt to equate the two different delivery methods.

Understanding the One-Third Rule in Oxygen Delivery

The equivalence mainly arises from a general rule of thumb used in respiratory care, which suggests that during rest, a person typically breathes in, or inhales, for about one-third of the respiratory cycle. Based on this, some have concluded that if you need a continuous flow of 3 liters per minute (LPM), you might only need a pulse dose of oxygen that would add up to 1 liter over a minute since you're only actually breathing in for one-third of that time.

Theoretical Equivalence Calculations

Let's break down the math using this one-third rule. If an oxygen concentrator is set to deliver a pulse flow equivalent to 5LPM, it needs to provide enough oxygen during each inhalation to match what would be one-third of that 5LPM continuous flow. So theoretically, that means delivering approximately 1.666 liters of oxygen every minute but only during inhalation periods. For a setting that claims to be equivalent to 1LPM, it would need to deliver about 0.333 liters per inhalation period, which is roughly 333 milliliters.

It's important to remember, however, that these calculations are based on a theoretical framework and assume a standard breathing pattern, which can vary widely among individuals and with different activity levels.


5. What Do Actual Pulse Flow Gear Settings Indicate?

Pulse flow concentrators have settings that indicate the amount of oxygen delivered with each breath, but these numbers need some explanation to understand what they actually mean in practical terms.

Typical Milliliters per Gear in Pulse Flow Devices

In pulse flow devices, each setting or "gear" correlates to a specific volume of oxygen delivered in milliliters (ml). For example, setting 1 might deliver 333 ml per breath, while setting 2 delivers 666 ml, and so on. These volumes are preset by the manufacturer and differ between models and brands.

Discrepancy Between Theoretical and Practical Output

The actual oxygen output on pulse settings can vary, and this is where the theoretical equivalence to continuous flow gets complicated. While manufacturers may provide an equivalent LPM rating for their pulse flow settings, in practice, the amount of oxygen received can be less than these values suggest.

This discrepancy arises because individual breathing patterns, activity levels, and even the specific design and efficiency of the oxygen concentrator can affect performance. Moreover, theoretical calculations don't always take into account factors such as how deeply a person inhales or whether they're at rest or moving around.

Therefore, while the gear settings on a pulse flow device offer a general guide to the volume of oxygen delivered per breath, the real-world application might result in different amounts of oxygen being provided than the pure numbers would indicate.

6. How Does This Affect Portable Oxygen Concentrator Performance?

The way pulse flow settings work has a direct impact on the performance of portable oxygen concentrators, especially when considering their size and capacity.

Variations in Gear Pulse Flow Among Small-Sized Portables

Portable oxygen concentrators are designed to be lightweight and easy to carry around. However, this portability often comes with a trade-off in terms of oxygen output. Smaller devices may not be able to deliver as high a volume of oxygen per pulse setting compared to larger, less mobile units. Each model has its own specifications for how many milliliters of oxygen it delivers at each setting. For instance, one device might provide 666 ml per breath on setting 2, while another might offer only 420 ml at the same setting.

Real-World Implications of Reduced ml per Gear

When a portable oxygen concentrator provides less oxygen per setting (ml per gear), it can have tangible effects on the user. When you’re engaged in physical activities, your body’s demand for oxygen increases compared to when you’re at rest. A small dosage of oxygen might not be as effective, and there could be a significant difference in its effectiveness compared to a larger dosage. This is particularly noticeable during physical activity, where your breathing rate increases and you need more oxygen.

For those relying on precise oxygen doses for their health, understanding the actual output of their portable concentrator is vital. It ensures that they receive enough oxygen to maintain their activity levels without compromising their health. Healthcare providers often have to take these variations into account when prescribing oxygen therapy and might suggest specific models that better match a patient's lifestyle and oxygen requirements.

7. Who Might Not Benefit From Pulse Mode Oxygen Delivery?

Pulse-mode oxygen delivery isn't suitable for everyone. Its effectiveness can depend on a person's specific respiratory needs and patterns.

Considerations for Individuals with Specific Breathing Patterns or Conditions

Individuals who breathe through their mouths, breath through the throat, or suffer from conditions like chronic obstructive pulmonary disease (COPD) in its later stages may not benefit as much from pulse mode. This is because the technology relies on detecting when the user takes a breath in through their nose to deliver oxygen. If this inhalation isn't detected, the device won't release oxygen, which could mean that the individual doesn't receive the necessary amount.

When Is Continuous Flow Recommended Over Pulse Mode?

Continuous flow is often recommended for those who need supplemental oxygen while sleeping, as breathing naturally becomes slower and shallower during sleep, which might not trigger the pulse system effectively. It's also favored for individuals with high oxygen demands of more than 5 LPM or those with certain health conditions that require a steady supply of oxygen regardless of their breathing pattern.

8. Can Pulse Flow Settings Be Customized to Individual Needs?

Yes, pulse flow settings can be adjusted, offering some level of customization to meet individual respiratory requirements.

Discussion on Adjustability of Pulse Flow Settings

Given that the equivalent effect of pulse flow can fluctuate under different activity conditions, users may need to modify the flow settings when their oxygen saturation (SPO2) falls below or exceeds their oxygen therapy requirements. This adjustment ensures that their SPO2 aligns with the prescribed levels. However, it’s crucial that users seek professional medical advice to receive accurate guidance.

How to Work with Healthcare Providers to Find the Right Setting

Finding the optimal pulse flow setting is critical and should be done with the assistance of a healthcare provider. They will consider factors such as your resting oxygen saturation levels, exertion levels, and overall health to determine the best setting. Furthermore, regular check-ins are crucial, as oxygen requirements can change over time with changes in health status or activity levels. By working together, you and your healthcare provider can ensure that your oxygen therapy is tailored to your current needs, maximizing the benefits of your portable concentrator.

Final Thoughts: Understanding Pulse Flow Versus Continuous Flow

While pulse flow oxygen delivery offers a convenient and energy-efficient option for those requiring supplemental oxygen, it's essential to understand the nuances between pulse and continuous flow settings. Pulse mode isn't a one-size-fits-all solution; its effectiveness hinges on individual breathing patterns and specific health needs. Adjusting the settings with the guidance of healthcare professionals ensures that patients receive the appropriate amount of oxygen, whether they're on the go or at rest. Acknowledging the limitations and adaptability of portable oxygen concentrators allows users to manage their oxygen therapy effectively and maintain their lifestyles as seamlessly as possible.

Read More

About Writor


Hilary, an oxygen concentrator expert, brings 11 years of experience working with manufacturers. With a wealth of market knowledge, he adeptly navigates the intricacies of various oxygen concentrator models, providing consumers with insightful content on oxygen technology.


How to Choose Portable Oxygen Concentrators for Elderly Patients
Can You Sleep with a Portable Oxygen Concentrator?

Hinterlasse einen Kommentar

Diese Website ist durch reCAPTCHA geschützt und es gelten die allgemeinen Geschäftsbedingungen und Datenschutzbestimmungen von Google.