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Continuous positive air pressure therapy, or CPAP for short, is one of the most effective therapies for those with sleep apnea. Sleep apnea is a medical disorder characterized by shallow breathing, snoring, and temporary loss of breath during the night.
CPAP machines are compact devices that draw in outside air using a built-in fan; the machines then humidify the air and pressurize it before delivering it to the sleeper via a connective hose and face mask. Standard CPAP machines pressurize air to certain levels, measured in centimeters or water, or cmH20. Most CPAP machines provide a pressurizing range of 4 to 20 cmH20; pressure levels are fixed, depending on the sleeper’s prescribed setting.
Automatic CPAP – or APAP – machines operate differently. Rather than maintaining one pressure setting, these devices provide variable pressurization based on the sleeper’s breathing patterns. This function makes APAP machines more comfortable for some users than CPAP machines. This is particularly true for those with central sleep apnea (CSA), which occurs when the brain is unable to send signals to muscles that control breathing. Like standard CPAP machines, APAP machines, humidifiers, and breathing masks require a doctor’s prescription.
Read on to learn more about APAP machines, how they work, and why they are different from other CPAP devices. Below you’ll find our top picks for APAP machines sold today. Our choices are based on verified customer and owner experiences, along with intensive product research and analysis.
Our Editor’s Pick, the ResMed AirSense 10 AutoSet, is a standout APAP machine for several reasons. The device is engineered for expiratory pressure relief (EPR), which administers the prescribed setting during inhalation and low-pressure settings during exhalation. This allows those with sleep apnea to breathe in and out more easily throughout the night.
The AirSense 10 AutoSet also comes with a built-in humidifier; its 380-mL tank is larger than average. Users can set the humidifier at eight different levels, depending on their preferences. The Run Warmup function allows users to warm up the water in the humidifier before bedtime, resulting in more comfortable air delivery. At 26 decibels (dB), the machine is also fairly quiet and should help cut down on sleep disturbances, particularly for those who find other APAP machines too noisy.
The manual controls have LCD backlighting, which is easier on the eyes. Users can use the MyAir app to access and adjust their machine’s settings remotely using a smartphone or tablet. ResMed backs this device with a two-year warranty.
Most APAP machines are relatively small and lightweight, but still somewhat bulky and difficult to fit into packed suitcases. The Transcend 3 miniCPAP Auto from Somnetics is a rare exception: the device measures less than 4″ thick and barely weighs one pound. The machine is ideal for air travel; the FAA approves it for in-flight use, and it has a maximum operating altitude of 8,000 feet.
In the event of leakage, the machine will increase pressurization to compensate for lost air. It is also fairly quiet, with an operating volume of roughly 26.6 dB. The Transcend 3 miniCPAP Auto is also easy to clean while traveling; thanks to an innovative ‘Drying Mode’ function, the device activates a stream of warm air through the connective hose that reduces germs, mold, and other contaminants.
The EZEX Pressure Relief setting is another helpful feature; the machine gradually increases pressure once the user falls asleep, ensuring travelers get a good night’s rest with minimal breathing difficulty. Somnetics backs the Transcend 3 miniCPAP Auto with a three-year warranty.
The innovative SleepStyle Auto device from Fisher & Paykel is our Best Features pick. The machine includes a built-in humidifier with AirSpiral technology that minimizes condensation between the generator and the breathing mask, resulting in easier breathing throughout the night.
The SleepStyle Auto also tracks breathing patterns, nocturnal movements routines, and other sleeper metrics; owners can access their data using the SleepStyle app. The SensAwake function provides a gradual ramp-up in pressurization after the user falls asleep to help alleviate discomfort during exhalations.
Despite these features, the device is relatively compact, thanks to an integrated design that saves space and provides easy access to the reservoir. A clean interface with large, user-friendly controls makes the machine suitable for all users – even those who are new to APAP therapy. A travel-size bag is included with each purchase, as well. Fisher & Paykel backs the SleepStyle Auto with a two-year warranty.
Continuous positive air pressure (CPAP) therapy is highly beneficial to those with sleep apnea, particularly those who experience heavy apnea-related snoring. Standard CPAP involves one fixed air pressure setting. In recent years, automatic positive air pressure, or APAP, has become a popular alternative to standard CPAP therapy because it adjusts pressure settings based on the sleeper’s breathing patterns. For many, APAP therapy is a less intrusive and more comfortable treatment for sleep apnea symptoms than CPAP.
In this guide, we’ll discuss what APAP machines do and how they work. We’ll also discuss types of APAP devices, and how they differ from other CPAP machines. Read on to learn more.
Automatic positive air pressure, or APAP, is a type of positive air pressure (PAP) therapy. During PAP therapy, air is humidified, pressurized, and delivered to sleepers via connective hose and breathing mask. This type of therapy is optimal for those with conditions that make breathing difficult.
Most PAP users have the condition known as sleep apnea, an uncomfortable condition characterized by temporary loss of breath during the night; these episodes typically last 10 seconds or less, and do not usually pose a threat to sleepers. However, some people with sleep apnea experience more than 100 episodes during the night. This results in frequent discomfort, as well as loss of sleep quality. Many people with sleep apnea snore heavily, as well.
There is no cure for sleep apnea, but PAP therapy is considered the most effective treatment for this condition’s main symptoms. Although sleep apnea symptoms vary by individual, two primary types of apnea have been identified.
There are also three common types of PAP therapy administered to sleep apnea patients: continuous PAP, or CPAP; bi-level PAP, or BiPAP; and automatic PAP, or APAP. The key differences between these three therapy types are outlined in the table below.
|Therapy Type||Function||Air Pressure Levels||Best Used for...||Average Price Range|
|CPAP||Air pressure increases until it reaches the prescribed rate||One fixed level; CPAP machines deliver air pressure at one setting||People with OSA; those with CSA often need more than one pressure setting||$200 to $800|
|BiPAP||Air pressure is delivered at two different levels, a higher setting for inhalation and a lower setting for exhalation||Two fixed levels; both the inhalation and exhalation settings are fixed based on the sleeper’s prescription||People with CSA, as well as those with OSA who have other medical conditions that make exhalation difficult||$800 to $1,700|
|APAP||Air pressure automatically adjusts to different pressure settings during inhalation and exhalation||No fixed levels; the pressure will adjust based on the sleeper’s breathing patterns||Because it automatically adjusts air pressure based on individual breathing, APAP can be used for OSA or CSA||$600 to $800|
APAP therapy is, for many, a more comfortable experience than CPAP or BiPAP therapies because the pressure changes based on the sleeper. CPAP with one fixed setting and BiPAP with two cannot acclimate to the sleeper’s breathing patterns; by design, both CPAP and BiPAP machines have fixed settings that prevent automatic adjustment. Professionals calibrate these settings based on the sleeper’s doctor’s prescription, which is required to legally purchase a CPAP or BiPAP machine.
APAP machines are not calibrated in the same way. They have a feature known as A-flex, which automatically increases air pressure when the sleeper inhales and then lowers the pressure when they exhale. This allows APAP machines to adjust based on the sleeper’s breathing, rather than delivering air at a prescribed pressure rate – though it’s important to note that APAP machines also require a prescription.
The air pressure settings are measured in centimeters of water, or cmH20. Although pressure setting options vary somewhat by model, the vast majority offer a range of 4 cmH20 to 20 cmH20.
Next, we’ll look at common features included with most APAP machines.
Apart from the A-flex feature, which is exclusively found in APAP machines, many APAP components are also found in CPAP machines. These include the following:
Lastly, APAP therapy requires use of a breathing mask. The three most common mask types are full face, nasal cradle, and nasal pillow. The table below breaks down the three most common types of APAP breathing masks.
|Mask Type||Full Face||Nasal Cradle||Nasal Pillow|
|Appearance/shape||Mask forms a tight seal from the bridge of the nose to the bottom of the mouth||Mask forms a tight seal from the bridge of the nose to the upper lip||Mask fits into both nostrils, with a coverage area extending from the tip of the nose to the upper lip|
|Features||Mask is secured with straps keep it in place||A chinstrap may be used to hold the mouth closed||A cushion holds the mask in place and provides extra comfort|
|Most suitable for...||PAP therapy users who need air with high-pressure settings People who breathe through their mouths and/or struggle with nose-breathing Back sleepers||PAP therapy users who need air with high-pressure settings Sleepers who frequently toss and turn Side sleepers||PAP therapy users who need air at low pressure settings People who wear glasses or have thick facial hair Side sleepers|
|Not as suitable for...||Side or stomach sleepers People who wear glasses People with thick facial hair||People who primarily breathe through their mouth People with allergies that cause nasal blockage||PAP therapy users who need air with high-pressure settings People who primarily breathe through their mouth People with allergies that cause nasal blockage|
|Average price range||$80 to $150||$80 to $110||$50 to $75|
All three breathing masks offer universal compatibility, meaning they can be used with any APAP machine. It’s important to note that the APAP machine, humidifier, and breathing mask each require a doctor’s prescription. A machine may be sold with a built-in humidifier or the humidifier may be sold separately; breathing masks are always sold separately. For more information on this topic, please see our ‘APAP Prescription Requirements’ section below.
Operating an APAP machine is fairly straightforward. For most devices, the process is as follows:
1. Position the APAP machine on a flat, even surface that can support its weight. APAP machines always have flat bases.
2. Connect the machine’s power cord to an outlet or power strip.
3. If the humidifier is integrated, fill the reservoir with distilled water using a pitcher; if it is detachable, fill the reservoir with distilled water using a faucet and then attach to the machine.
4. Check to make sure the connective hose is secure between the airflow generator and the breathing mask.
5. Put on the face mask and adjust to a comfortable position.
6. Turn on the machine.
CPAP machines typically need a few minutes to reach the prescribed pressure setting; this is known as ramp time. Because they don’t have a fixed setting, APAP machines do not need as much ramp time – though sleepers that initially need a high-pressure setting may need to wait a few minutes.
Advantages of using an APAP machine include:
Disadvantages of using an APAP machine include:
Sleep apnea type is not a major concern when choosing a new APAP machine, since these devices can effectively treat both OSA and CSA. However, APAP machine shoppers should take the following factors into account:
Lastly, APAP machine shoppers should consider their prescription. In the next section, we’ll cover the key prescription requirements for purchasing these devices.
Some of the most common prescription-related questions about APAP therapy are answered below.
Yes. A prescription is required for the APAP machine, humidifier, and breathing mask. The U.S. Food and Drug Administration (FDA) regulates the sale of these three components. Other APAP components, including the air filter and connective hose, do not require a prescription.
The FDA requires a prescription for two reasons. The first is medical liability. Doctors write PAP therapy prescriptions after evaluating the patient for sleep apnea symptoms. The prescription includes recommended air pressure levels, based on the patient’s results. APAP machines are calibrated for a certain pressure range, based on the lowest and highest optimal settings for the patient. Incorrect calibrations can actually worsen symptoms of sleep apnea, rather than alleviate them. For this reason, an APAP machine user should never attempt to recalibrate the machine themselves.
The second reason is related to insurance. Patients do not need medical insurance to purchase APAP machines, humidifiers, or breathing masks. However, insurance companies mandate the prescription because some buyers cannot afford to pay for these devices out-of-pocket.
No. Your doctor may write a prescription that specifically calls out APAP therapy, but you can also use a CPAP prescription to purchase FDA-regulated APAP hardware.
Yes. The FDA categorizes APAP machines, humidifiers, and breathing masks as Class II medical devices. Those who sell Class II devices can only do so after receiving FDA approval, and they may only sell these devices to buyers with a prescription.
Technically, you can buy APAP machines, humidifiers, and masks without a prescription, but you are breaking the law and so is the seller. In addition to legal repercussions, transactions of this nature are also ill-advised. Most take place online on private sale websites, and involve machines that have been used, refurbished, and/or modified. Alterations to the APAP machine carry health risks, including complications due to using improperly calibrated equipment and exposure to germs and bacteria from previous owners. Furthermore, the buyer receives no guarantee the item is in working order and will not qualify for any sort of warranty coverage.
Bottom line: we highly discourage you from purchasing an APAP machine, humidifier, or breathing mask without a prescription; buying these items from an FDA-approved medical device seller is strongly recommended.
A sleep apnea diagnosis is needed for an APAP prescription. You must consult with one of the following certified professionals in order to obtain this prescription:
However, most APAP device sellers will not accept prescriptions from chiropractors, optometrists, or psychologists.
The prescribing physician may diagnose you with sleep apnea or issue a home sleep test (HST). Some may refer you to a sleep disorder specialist instead. These specialists also commonly issue HSTs; they may also conduct polysomnography sleep tests that record brain waves, blood oxygen levels, and eye movements. The HST is less invasive but results tend to be inconclusive; for this reason, many patients undergo the HST and polysomnography tests.
An APAP prescription must include the following:
The prescription requirements for an APAP machine can be somewhat confusing. For a more detailed analysis, please visit our CPAP, BiPAP, and APAP Prescriptions guide.
For some sleepers, APAP and other forms of PAP therapy may not be the most effective treatment method for sleep apnea symptoms. For others, additional measures are needed. Let’s look at some alternate devices and sleep strategies that can also benefit people experiencing OSA or CSA.
The following products help alleviate snoring, irregular breathing, and other apnea-related symptoms
Mandibular advancement devices (MADs): MADs are anti-snoring mouthpieces designed to fit inside the sleeper’s lower jaw (also known as the mandible). The device pushes the jaw forward, which expands the airway to help reduce snoring episodes. Some MADs are custom-molded; the sleeper bites into a malleable material, forming an impression, and then mails their mold to the manufacturer. Other MADs, known as ‘boil-and-bite’ models, become softer in hot water; this allows owners to create the impression themselves without custom fitting. A MAD may require a prescription, but many over-the-counter options are available.
Tongue retaining devices (TRDs): TRDs, like MADs, are anti-snoring mouthguards, but they operate differently. Rather than repositioning the jaw, TRDs pull the tongue forward using a suction system; this widens the gap between the tongue and the airway. Many TRDs resemble baby pacifiers, and most are one-size-fits-all models that do not need to be custom-molded. TRDs rarely require a prescription.
Provent: Provent therapy is a recently developed apnea treatment that has been approved by the FDA. Provent therapy consists of two small valves with air filters; the valves are placed in each nostril using a non-toxic and hypoallergenic adhesive. The valves open to ease inhalations, then close during exhalation to build pressure in the breathing passages and keep the airway open. Provent can reduce apnea-related breathing episodes and cut down on snoring. A prescription is required.
Oral surgery: Sleep apnea patients with severe symptoms may be good candidates for oral surgery. A physician will make surgery recommendations based on the patient’s individual symptoms. Some of the most common procedures include: uvulopalatopharyngoplasty (UPPP), during which the uvula is removed to strengthen the soft palate; genioglossus advancement (GGA), during which tongue tendons are stretched away from the patient’s throat; and maxillomandibular advancement (MMA), during which the upper and lower jaw are permanently readjusted. Oral surgery can be very expensive, but it is also highly effective.
In addition to the devices listed above, sleepers may be able to alleviate snoring and other apnea symptoms through the following measures:
Try side sleeping: Sleep position can affect sleep quality and duration for those with sleep apnea. Side sleeping is considered the best position for those with this condition, particularly the OSA type. Sleeping on one’s side causes the tongue to fall away from the throat, which allows the esophagus to expand. Comparatively, back sleeping is considered the worst position for those with sleep apnea because the tongue is much more likely to block the airway. Stomach sleeping, like side sleeping, may result in less airway blockage; however, most doctors discourage this position because it leaves sleepers more vulnerable to neck and shoulder pain.
Buy a thicker/thinner pillow: Pillow loft, or thickness, plays a significant role in sleep quality and duration for people with sleep apnea. Many people with this condition experience fewer shallow breathing and snoring episodes when their head and neck are elevated. This is especially true for those who insist on sleeping on their backs.
Pillow loft is divided into three general categories: low loft (thinner than 3″); medium loft (3″ to 5″); and high loft (thicker than 5″)
When choosing a pillow based on loft, consider the following:
To learn more about loft and other pillow selection factors, please visit our Pillow Buying Guide.
Consider an adjustable bed base: Adjustable beds can be raised at the head. This allows owners to sleep with their head and neck at an elevated angle, which can reduce snoring and apnea-related breathing episodes. Modern models offer a wide range of elevation angles, so most sleepers can find a setting that works best for them. Additionally, many adjustable beds are split down the middle, offering different elevation levels for couples.
Depending on the model, an adjustable bed may have manual, remote, and/or app-based controls. One thing to keep in mind: adjustable beds can be very expensive. The baseline for most models is about $1,000, but some cost more than $3,000. To learn more about these products, check out our Adjustable Bed Buying Guide.
Lifestyle changes: The Mayo Clinic recommends the following lifestyle changes for people with sleep apnea:
To learn more about sleep apnea, PAP therapy, and other related topics, please visit the following pages on Tuck.com.