How CPAP Machines Help Treat Sleep Apnea

Quick Takeaways:

•  Continuous positive airway pressure (CPAP) therapy is one of the most effective treatments for sleep apnea. It uses gentle, steady air pressure to keep your airway open while you sleep.

• With regular use, CPAP can improve sleep quality, boost energy and reduce long-term risks like high blood pressure and heart disease.¹⁵

•  Finding the right mask and pressure settings can make a big difference in comfort and treatment success.
• Modern CPAP machines include features like humidifiers, ramp settings, and mobile apps to make therapy easier to adjust to and track. 

Whether you’ve just been diagnosed with obstructive sleep apnea (OSA) or are simply exploring treatment options, it can be helpful to know that continuous positive airway pressure (CPAP) is one of the most effective ways to manage OSA and improve your sleep and overall health.¹

But how does CPAP work? And what do you need to know about using CPAP?

Below, learn more about OSA and CPAP, including how this treatment works, tips for making it work for you and where you can find CPAP support, education and solutions.

Understanding sleep apnea and CPAP therapy

Before diving into how CPAP works, it helps to understand what causes sleep apnea and why therapy can make such a powerful difference.

What is sleep apnea?

 Sleep apnea is a condition where breathing stops and restarts many times while you sleep. This can make it harder for your body to get enough oxygen. The most common type is obstructive sleep apnea (OSA), which occurs when the muscles around the throat relax to the point of collapse, restricting airflow during sleep. Breathing may become shallow or stop for seconds to minutes at a time.²

 When you sleep, your entire body relaxes, including the muscles in your nose, mouth and throat that help keep your airway open so that air can get into your lungs. For people with OSA, when these muscles relax, the airway collapses or becomes obstructed. This temporarily stops your breathing and prevents oxygen from getting into your lungs.³

Because many of the symptoms of sleep apnea occur when you’re asleep, it can be challenging to recognize them. However, there are key signs to look for. One of the most common symptoms of OSA is excessive daytime sleepiness, which may cause you to feel unusually tired or drowsy despite getting a full night's sleep.¹⁸ People with OSA may , choke or gasp for breath while asleep or experience frequent snoring that keeps their bed partners awake.⁴

How CPAP therapy works

Continuous positive airway pressure (CPAP) is a drug-free sleep apnea treatment that uses mild, continuous air pressure to keep the airway open while you sleep. It doesn’t breathe for you – it delivers consistent pressure to your airway as you breathe in your sleep. CPAP is highly effective and is the most used and understood method for treating sleep apnea.¹⁶

This pressure helps keep the upper airway open and pushes pressure into the alveoli, which are the small air sacs in the lungs where oxygen enters the blood. The pressure helps expand these air sacs, increasing the surface area, which can help support healthy oxygen levels.⁵ 

CPAP components and system overview 

There are several CPAP devices to choose from, and they typically have the same basic components: a mask, tubing and the CPAP machine itself. For adults, CPAP usually involves wearing a mask that either covers the entire nose or sits just under it to deliver steady air throughout the night. Some CPAPs use a full-face mask, which covers both the mouth and nose.⁵

CPAP pressure is measured in centimeters of water (cm H₂O). Doctors typically aim to set the lowest effective pressure needed to help prevent breathing pauses during sleep. For many adults, this often falls within a range like 6 to 14 cm H₂O..⁶

Clinical Benefits of CPAP Therapy

Why is CPAP the go-to treatment for obstructive sleep apnea (OSA)? Learn more about the health benefits of CPAP below.

Immediate effects on the body

Once you start using your CPAP, you may notice improvements right away — which can include better sleep quality, reduced snoring and less daytime sleepiness.⁷ The continuous pressure created by CPAP helps keep the airway open during sleep, which supports healthy oxygen levels.

Long-term health benefits 

While you may start to feel more rested early on, consistent CPAP use can lead to other health benefits over time. 

Unsurprisingly, using a CPAP machine can also have a significant impact on sleep quality, which has a range of health benefits. Better sleep can lead to healthier weight management, a stronger immune system, improved mood and reduced stress.⁸ 

Measuring treatment effectiveness

One way to tell if CPAP is making a difference for you is to consider how you feel after you start using it. Do you feel well-rested in the morning? Do you feel like you’re getting a good night’s sleep? Have your bed partners noticed any changes, such as less snoring while you sleep? These questions can help you reflect on your CPAP experience and guide conversations with your doctor.

That said, there are other, more objective ways to measure CPAP benefits.

In many cases, a sleep study is used to diagnose OSA prior to your doctor prescribing CPAP therapy. These studies use a measurement called the apnea hypopnea index (AHI) to determine the severity of your sleep apnea. For example, someone with an AHI of less than 5 does not have OSA, while someone with an AHI over 30 is considered to have severe OSA.⁹ CPAP therapy is generally recommended for everyone who's been diagnosed with OSA.¹⁹

Assessing the effectiveness of CPAP treatment can vary by case. Most people will be asked to see their doctor in about 30 to 90 days after starting CPAP therapy. At this time, your doctor will likely ask you questions about your sleep (such as whether your sleep quality has improved) or your daytime symptoms (such as if you are feeling less daytime tiredness).¹⁰

Your CPAP machine collects data about how many times your breathing becomes shallow or pauses completely per hour, and whether your mask is properly in place as you sleep. Your doctor will analyze this data to determine how effective your treatment is and how regularly you are using the device. With this information, they may increase or decrease your pressure settings or discuss trying a different style mask to help make CPAP work better for you.¹⁰

Making CPAP Therapy A Success

While CPAP is an effective treatment option for OSA, it can take some getting used to. Your doctor will prescribe pressure settings tailored to your needs, but there are things you can consider to help set yourself up for success.

Personalized pressure settings

Your doctor will determine how much pressure you need to help keep your airway open while you sleep. To get the pressure setting right, your doctor may have you participate in an overnight CPAP study. During this, a healthcare professional will adjust your CPAP pressure to find the setting that helps reduce breathing interruptions while you sleep. 

Typically, the goal is to find the lowest pressure setting that keeps your breathing steady throughout the night.⁶

Some modern CPAP machines, like Resmed’s AirSense™ 11, can auto-adjust to change the level of pressure on a breath-by-breath basis, creating a treatment that is truly tailored to your needs. For example, this automatic adjustment can account for factors such as the position you’re sleeping in that may impact the amount of pressure needed for each breath.

DISCLAIMER: ALWAYS READ THE LABEL AND FOLLOWS THE INSTRUCTIONS FOR USE. IF SYMPTOMS PERSIST, TALK TO YOUR HEALTHCARE PROFESSIONAL.

With sleep apnea, positioning yourself on your side can help keep your airway open compared to sleeping on your back.¹¹ Therefore, you may need less pressure from your machine when sleeping on your side. A machine like the AirSense 11 is designed to automatically make these adjustments for you, which can help improve CPAP comfort.

Comfort features to help you stick with your treatment

Air coming from a CPAP machine may travel through the nose quicker than the body can fully warm and moisten it. That’s why proper humidification can be important for improving CPAP comfort. It may help reduce issues like dry mouth, dry nose, chapped lips, nose bleeds and even sinus headaches.¹²

Some CPAP machines, like the AirSense™ 11, offer a ramp feature, which may help you fall asleep more easily with your CPAP.²⁰ With a ramp feature, the CPAP starts with a lower amount of pressure when you turn it on, increasing to the prescribed level of pressure over time. This slow increase can help you settle into sleep as the pressure being used by the CPAP is lowest right after you turn it on.

Finding the right mask based on your face and how you like to sleep can impact your CPAP therapy success. There is a wide range of CPAP masks in a variety of styles and fits to help you find one that works for you. Your doctor or CPAP equipment provider can help you determine which mask may be a good fit and show you how to correctly wear the mask so you can avoid air leaks.

For example, full face masks may be a good option for people who breathe through their mouth or have frequent sinus problems. On the other hand, nasal masks are typically smaller in size and come in various styles, including over and under the nose.¹³ 

Education and support

It's completely normal for it to take some time to get used to using a CPAP device. Proper education about the equipment and what to expect may help make the transition easier. You can talk to your doctor or sleep specialist about the educational resources they recommend.

If you're having trouble adjusting to CPAP therapy and looking for support, consider the following tips:

• Talk to your doctor about any problems you’re having. They can provide suggestions to make your experience with CPAP more comfortable.

• Ask your doctor about whether using a different mask is an option. Everyone is different, and CPAP masks are not one-size-fit-all. Some people may prefer the fit or feel of one type of mask over another.

• If you use a nasal mask and sleep with your mouth open, talk to your doctor about whether a chin strap is an option you can try instead of a full-face mask. ²⁰

• Consider a CPAP device that automatically adjusts pressure or has a ramp feature.

• If you have tried multiple options and are still struggling, ask your doctor about other sleep apnea treatment options.¹⁴

Note that you may need to go back to see your doctor periodically to ensure the pressure setting is right and that you are experiencing the full benefit of your CPAP. In some cases, an overnight sleep study can help rule out any issues, fine-tune your treatment or help determine why your CPAP hasn’t been working as well as it should.¹⁰

Resmed CPAP solutions

Resmed CPAP devices such as the AirSense™ 11 has a number of features that can help you get started with CPAP and stay on track, including:

• A touchscreen that enables you to start and stop your CPAP therapy with just one tap.

• An integrated humidifier with climate control.

• The AutoRamp™ feature to keep your CPAP pressure low as you fall asleep before slowly increasing the pressure to your prescribed level.

• An expiratory pressure relief function that can support a smooth exhale.

If you travel, consider the AirMini Portable CPAP. This model is one of the smallest portable CPAPs on the market¹⁷ and works with Resmed CPAP masks, so you can take your regular mask with you or invest in a second one for when you’re traveling. A waterless hydration system keeps you comfortable without having to worry about packing distilled water, and it comes with a premium travel bag and accessories for convenience.

DISCLAIMER: ALWAYS READ THE LABEL AND FOLLOWS THE INSTRUCTIONS FOR USE. IF SYMPTOMS PERSIST, TALK TO YOUR HEALTHCARE PROFESSIONAL.

To learn more about how you are responding to your CPAP therapy, Resmed offers the myAir ™ app, available on iOS and Android. In addition to providing online support, this app helps you track your progress, get encouragement and access resources to help you resolve common CPAP issues.

DISCLAIMER: myAir™ REQUIRES CELLULAR CONNECTIVITY. CELLULAR CONNECTIVITY DEPENDS ON NETWORK AVAILABILITY.

If you use an AirSense™ 11, the myAir™ app offers even more features, including videos and interactive, voice-guided instructions to help with equipment setup. You’ll also have access to support and coaching through Care Check-In, and the ability to change humidification settings, ramp time and tube temperature right from your phone.

At Resmed, we understand how a good night's sleep can change everything, and we're here to help you along every step of your sleep journey.

Are you or a loved one experiencing sleep issues or potential sleep apnea symptoms?

Take our home sleep test and discuss the results with your doctor.

 Home Sleep Test

DISCLAIMER: A SLEEP TEST IS NOT SUITABLE FOR EVERYONE. IT MAY NOT BE SUITABLE FOR YOU. PLEASE CONSULT YOUR HEALTHCARE PROFESSIONAL.

THE INFORMATION PROVIDED HERE IS FOR EDUCATIONAL PURPOSES ONLY AND SHOULD NOT BE CONSIDERED A SUBSTITUTE FOR PROFESSIONAL MEDICAL ADVICE.

References:

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17. Based on available user guide data from Resmed AirMini, Philips™ DreamStation® Go, Breas Z2® Auto System, Transcend® Micro™ and Z1 Auto.® The physical dimensions of AirMini are 5.4” (W) x 3.3” (D) x 2.1” (H).
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