- How Sleep Works
- Sleep Disorders
- Sleep Resources
- Sleep Health
- Sleep Medicine
Positive air pressure therapy, or PAP therapy, is a process for delivering airflow through a ventilation system to individuals who have a hard time breathing on their own. PAP therapy is delivered in one of two forms. Continuous positive air pressure, or CPAP, provides airflow at a fixed pressure rate; and bi-level positive air pressure, or BiPAP, delivers airflow at a variable pressure rate based on the user’s breathing patterns. PAP machines feature a generator attached to a humidifier that pressurizes the air, and a connective hose that links the generator to a mask placed over the user’s nose and/or mouth.
PAP therapy can be a highly effective treatment for people with sleep apnea; CPAP is normally reserved for people with obstructive sleep apnea (OSA), while BiPAP works best for people with central sleep apnea (CSA). This CPAP machine guide includes shopping considerations, our picks for the top CPAP models, and some additional strategies for people with OSA. First, let’s explore how CPAP machines work.
CPAP machines are considered the most effective treatment for obstructive sleep apnea (OSA), which is caused by partial or complete physical obstructions that block an individual’s airway. These obstructions lead to shallow breathing episodes throughout the night that can result in temporary loss of breath until the episode passes. Most shallow breathing episodes for people with OSA last 20 to 40 seconds, but more than 100 may occur over the course of a single night. Heavy snoring is a common symptom of OSA.
The other common type of sleep apnea, central sleep apnea (CSA), occurs when the brain cannot transmit proper signals to muscles that control breathing; there is no physical obstruction that affects breathing. However, CPAP machines are not as effective at treating CSA because they do not provide variable air pressure.
The table below details the key differences between CPAP and BiPAP machines.
|Machine||Type of Apnea Targeted||Function||Average Price|
|Continuous positive air pressure (CPAP)||Obstructive sleep apnea (OSA)||Pressure increases until it reaches prescribed rate||$200 to $800|
|Bi-level positive air pressure (BiPAP)||Central sleep apnea (CSA)||Pressure increases or decreases at variable rates, depending on the user’s breathing||$800 to $1,700|
CPAP machines operate using the same core components:
Another key component is the mask, which is sold separately from the machine itself. Masks are sold in different shapes and styles to accommodate different user preferences. Any style of mask can be used with a modern CPAP machine, provided the connective hose is compatible. Generally speaking, four primary types of mask are available:
To properly use a CPAP machine, follow this step-by-step process.
The output of a CPAP machine is usually measured in centimeters of water (or cmH20). Most sleep apnea patients require an airflow of at least 6 to 14 cm420, and CPAP machines usually deliver at least 4 to 20 cmH20. To determine how much is needed, apnea patients will typically undergo a sleep study before a CPAP machine is prescribed. It’s important to note that a prescription is required for all CPAP machines.
Benefits of using a CPAP machine for obstructive sleep apnea include the following:
Downsides of using a CPAP machine may include the following:
Type of sleep apnea: The choice between a CPAP or BiPAP machine is largely determined by the patient’s type of sleep apnea; CPAP is normally prescribed for OSA, while BiPAP is more suitable for CSA. However, BiPAP may be used to treat OSA if CPAP therapy has failed.
Price: The price of a new CPAP machine typically falls between $200 and $800. BiPAP machines tend to be more expensive than CPAP models.
Size and weight: Most CPAP machines are fairly compact, but some are larger than others — and users with limited bedroom space may wish to select a smaller model. Lighter machines are also more suitable for long-distance travel. Most CPAP machines come with a carrying case of some kind, regardless of size.
Operating pressure range: Apnea patients usually require airflow that falls between 6 and 14 cmH20. Most CPAP machines are designed to deliver an airflow of anywhere from 4 to 20 cmH20. That being said, purchasers should research the operating pressure range to determine if the device will meet their individual needs.
Ramp time: ‘Ramp time’ refers to the amount of time needed to reach the prescribed operating pressure after the PAP machine is turned on. Ramp time for most CPAP machines typically falls within 30 to 60 minutes.
Humidifier: Some PAP machines have built-in humidifiers that require owners to pour in water, while others have detachable humidifiers that can be removed from the machine and filled with water. Humidifier capacity is another important consideration, since larger humidifiers that hold more water may operate longer than those with smaller humidifiers.
Volume: CPAP machines almost always produce some noise, but certain models are quieter than others. Volume for CPAP machines is measured in a-weight decibels, or dbAs, which are used to express the relative loudness of air-based sounds.
Hose length: Most connective hoses that link CPAP machines to face masks are at least six feet in length, but users who are unable to set up their machine next to their bed may want a hose that measures even longer.
Power Source: Most CPAP machines operate on a voltage range of 100 to 240V AC. The power input requirements will be included in the product specs.
Operating altitude: CPAP machines are normally designed to properly function at certain altitudes; exceeding this altitude will compromise the delivery of properly pressurized air. This information is usually included in the product specifications.
Automatic controls: In addition to automatic on and off controls, some CPAP machines will adjust to the user’s shifting breathing patterns, as well as changes in altitude (which can affect the amount of pressure needed).
Alerts: Some CPAP machines will alert users if the pressure is turned off (due to issues such as power outage or dead batteries), if the mask leaves the user’s face, or if a leak develops in the connective hose. These alerts may take the form of audible alarms and/or LCD backlighting.
Sleep data: Like many electronic devices manufactured today, some CPAP machines are equipped with smart technology that monitors sleep patterns in users and provides readable data. This data may include how much pressure (in cmH20) is delivered each night, how long the machine is used, and how many days the owner has used the machine per week or month. CPAP machines may display this data on a built-in screen or via a mobile app.
Warranty: In most cases, a CPAP machine will come with a warranty that covers the product for two to five years, depending on the manufacturer.
Now, let’s look at the top-rated CPAP machines as voted by actual customers and owners. All customer satisfaction ratings are generated using authentic user experiences.
|Brand||3B Medical||DeVilbiss||Fisher & Paykel||Philips Respironics||ResMed|
|CPAP Model||RESmart||IntelliPAP Standard||ICON Premo||DreamStation||AirSense 10 Elite|
|Dimensions (machine and humidifier)||12.3L” x 7.6W” x 4.4H”||6.4L” x 6.5W” x 8.4H”||6.3L” x 6.7W” x 8.7H”||11.7L” x 7.6W” x 3.3H”||10L” x 4.6W” x 5.9H”|
|Weight (est.)||3.5 lbs||4.5 lbs||5 lbs||4.5 lbs||5 lbs|
|Operating pressure range||4 to 20 cmH20||3 to 20 cmH20||4 to 20 cmH20||4 to 20 cmH20||4 to 20 cmH20|
|Ramp time||0 to 60 minutes||0 to 45 minutes||0 to 20 minutes||0 to 45 minutes||0 to 30 minutes|
|Humidifier capacity||N/A||400 mL||420 mL||325 mL||380 mL|
|Sound volume||Less than 30 dbA||26 dbA||Less than 29 dbA||26 dbA||27 dbA|
|Hose length||6 feet||6 feet||6 1/4″ feet||N/A||6 feet|
|AC/DC Power voltage range||100 to 240 V AC||100 to 240V AC|
|100 to 240V AC||100 to 240V AC|
|100 to 240V AC|
|Operating altitude (est.)||8,200 feet||9,000 feet||9,000 feet||7,500 feet||8,500 feet|
|Carrying case included?||Yes||Yes||Yes||Yes||Yes|
|Warranty length||2 years||5 years||2 years||2 years||2 years|
|Tuck Customer Satisfaction Rating||93% (132 customer reviews)||95% (372 customer reviews)||94% (69 customer reviews)||92% (35 customer reviews)||97% (42 customer reviews)|
If a CPAP machine does not treat a patient’s sleep apnea or proves insufficient, people with OSA or CSA may be able to reduce their nighttime sleep disruption through the following means.
Non-mask devices: CPAP machines may not be suitable for certain users due to factors like sound volume, size, or price-point. In these cases, individuals may want to seek out simpler devices. One potential alternative is Provent, a sleep apnea treatment method developed at Stanford University. Provent does not utilize a generator or a mask. Instead, it features two small, disposable devices equipped with air filters that fit into both nostrils.
Provent is FDA-approved and clinically proven; apnea patients who are interested in Provent or other alternative apnea treatments should consult their physician.
Optimal pillow loft: Many people with sleep apnea — particularly those with OSA — are more susceptible to snoring when they sleep on their backs with their head at an elevated position. For this reason, people with sleep apnea are often encouraged to sleep on their sides, but this may not be suitable for certain individuals. Those who wish to continue sleeping on their backs may be able to reduce snoring by optimizing their pillow ‘loft,’ or thickness.
‘High-loft’ pillows are thicker than five inches (5″), ‘medium-loft’ pillows are three to five inches (3″ to 5″) thick, and low-loft pillows are thinner than three inches (3″). When determining the best pillow loft, it’s important to consider the following factors:
The table below provides a detailed breakdown of the three general pillow loft categories.
|Loft||Thickness||Optimal Head Size||Optimal Weight||Optimal Shoulder Width||Optimal Mattress Firmness|
|Low||Less than 3″||Small||More than 230 lbs.||Narrow||Soft to Medium Soft|
|Medium||3″ to 5″||Average||130 to 230 lbs.||Average||Medium|
|High||More than 5″||Large||Less than 130 lbs.||Broad||Medium Firm to Firm|
For more information, please check out our Best Pillows — Buying Guide and Information page.
Adjustable Bed: Adjustable beds allow sleepers to adjust the angle of their sleep surface at the head and, in some cases, the feet as well. As is the case with optimal pillow loft, inclining the head at the right angle can help reduce snoring in people with sleep apnea. Additionally, some adjustable beds come with dedicated ‘anti-snore’ presets.
An adjustable bed may have manual, remote, or app-based controls. Most adjustable beds support anywhere between 600 and 800 pounds, making them suitable for most adults and their sleep partners. Models with dual-firmness may be most suitable for couples that have different firmness preferences.
Most adjustable beds cost at least $1,000, and some are priced at $3,000 or higher. For more information, please visit our Adjustable Bed Reviews page.