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Positive air pressure therapy, or PAP therapy, is a process for pressurizing and delivering airflow to individuals who have a hard time breathing on their own. PAP therapy may be delivered through continuous positive air pressure, or CPAP, provides airflow at a fixed pressure rate; or bi-level positive air pressure, or BiPAP, delivers airflow at a variable pressure rate based on the user’s breathing patterns.
PAP therapy can be a highly effective treatment for people with sleep apnea. While CPAP is normally prescribed for people with obstructive sleep apnea (OSA), BiPAP works best for people with central sleep apnea (CSA). This BiPAP machine guide will include buying considerations, our top picks for BiPAP brands and models, and some additional strategies for sleepers with CSA. First, let’s look at how BiPAP machines work.
BiPAP machines are considered the most effective treatment for CSA because they apply variable pressure to the airway. Central sleep apnea (CSA) occurs when the brain is unable to send proper signals to muscles that control breathing; unlike obstructive sleep apnea (OSA), there is no physical obstruction associated with CSA. People with CSA experience shallow breathing episodes that last 20 to 40 seconds, and may experience more than 100 per night.
BiPAP machines are considered the most effective treatment for CSA because they apply variable pressure to the airway. People with OSA may also be prescribed BiPAP therapy if CPAP machines are ineffective. The table below illustrates the main 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|
Standard BiPAP machines feature the following components:
The mask is usually sold separately from the BiPAP machine. Masks are sold in different shapes and styles to accommodate different fit preferences. Any style of mask can be used with a modern BiPAP machine as long as the connective hose is compatible to both. Four general types of mask are available:
To operate a BiPAP machine, follow this seven-step process.
The output of a BiPAP machine is measured in centimeters of water (or cmH20). Most sleep apnea patients require an airflow of at least 6 to 14 cm420, and BiPAP machines usually deliver between 4 and 25 cmH20. To determine how much is needed, apnea patients will typically undergo a sleep study before a BiPAP machine is prescribed to them. All BiPAP machines require a prescription.
Benefits of using a BiPAP machine for central sleep apnea include the following:
Downsides of using a BiPAP machine may include the following:
Type of sleep apnea: Although BiPAP machines are normally prescribed for central sleep apnea, they may serve as a last resort for individuals with obstructive sleep apnea who have not responded to CPAP therapy.
Price: BiPAP machines tend to be more expensive than CPAP models. The average BiPAP machine costs between $800 and $1,600.
Size and weight: BiPAP machines are all relatively compact, but available bedroom space may be a consideration for some shoppers. Lighter machines are also more travel-friendly. Most BiPAP machines come with a carrying case for easier transport.
Operating pressure range: Apnea patients usually require airflow that falls between 6 and 14 cmH20, and most BiPAP machines deliver between 4 and 25 cmH20 of airflow. Purchasers should double-check the operating pressure range to ensure the machine will meet their individual pressure needs.
Ramp time: ‘Ramp time’ is the amount of time needed to reach the prescribed operating pressure after the PAP machine is turned on. Ramp time for most BiPAP machines typically falls within 10 to 40 minutes. Alternatively, BiPAP machines equipped with ‘smart ramp’ technology will automatically increase or decrease pressure based on the user’s breathing; these models may not have a set ramp time.
Humidifier: A BiPAP machine may have a built-in humidifier, into which the user must pour water directly, or a detachable humidifier that can be brought to the sink. Generally, humidifiers with higher capacities will perform longer than those with lower capacities.
Sound volume: BiPAP machines always produce some noise, but certain models are quieter than others. Volume for BiPAP machines is measured in a-weight decibels, or dbAs, which express the loudness of air-based sounds.
Hose length: Most connective hoses that link PAP machines to face masks measure at least six feet in length, but users with limited space availability or outlet access may want a hose that extends further.
Power Source: Most BiPAP machines operate on a voltage range of 100 to 240V alternating current (AC), and may also operate using direct current (DC). Power input requirements are always included in the product specs.
Operating altitude: BiPAP machines are only designed to work at certain altitudes; exceeding this elevation will compromise how the air is pressurized and delivered.
Automatic controls: In addition to automatic on and off controls, some BiPAP machines will adjust to the user’s shifting breathing patterns and/or changes in altitude.
Alerts: Some BiPAP machines will alert users if the pressure is turned off, if the mask falls off, or if a leak occurs in the hose. Alerts may be delivered with an alarm and/or LCD backlighting
Sleep data: Most BiPAP machines sold today are equipped with smart technology that monitors sleep patterns in users and provides data readouts. This data may include how much pressure (in cmH20) is delivered on a nightly basis, how long the machine was used (in hours and minutes), and how many days the owner uses the machine per week or month.
Warranty: Most BiPAP machines come with warranties that cover the product for two to five years.
|Brand||3B Medical||DeVilbiss||Philips Respironics||Philips Respironics||ResMed|
|BiPAP Model||ReSmart BPAP 25A||IntelliPAP AutoBilevel||DreamStation BiPAP||PR System One REMStar 60 Series||AirCurve 10 S|
|Dimensions (machine and humidifier)||12.3L" x 7.6W" x 4.4H"||6.4L" x 6.5W" x 8.4H"||11.7L" x 7.6W" x 3.3H"||10.8L" x 6.5W" x 4H"||10L" x 4.5W" x 5.9H"|
|Weight (est.)||6.5 lbs||4.5 lbs||4.5 lbs||3 lbs||2.75 lbs|
|Operating pressure range||4 to 25 cmH20||3 to 25 cmH20||4 to 25 cmH20||4 to 25 cmH20||4 to 25 cmH20|
|Ramp time||0 to 10 minutes||0 to 45 minutes||Smart ramp||Smart ramp||0 to 20 minutes|
|Humidifier capacity||350 mL||300 mL||325 mL||325 mL||380 mL|
|Sound volume||Less than 30 dbA||26 dbA||26 dbA||29 dbA||27 dbA|
|Hose length||6 feet||6 feet||N/A||N/A||6 feet|
|AC/DC Power voltage range||100 to 240V AC||100 to 240V AC 12V DC||100 to 240V AC||100 to 240V AC 12V DC||100 to 240V AC|
|Operating altitude (est.)||8,200 feet||8,500 feet||7,500 feet||7,500 feet||8,500 feet|
|Alerts||Alarm||LCD||None||Alarm and LCD||None|
|Carrying case included?||Yes||Yes||Yes||Yes||Yes|
|Warranty length||2 years||5 years||2 years||2 years||2 years|
|Tuck Customer Satisfaction Rating||89% (26 customer reviews)||95% (18 customer reviews)||94% (22 customer reviews)||98% (31 customer reviews)||98% (17 customer reviews)|
If a BiPAP machine does not treat a patient’s central sleep apnea or proves insufficient, people with CSA may be able to reduce their nighttime sleep disruption through the following means.
Non-mask devices: BiPAP machines may not be a suitable CSA treatment method due to factors like sound volume, size, or price-point. If this is the case, people with CSA may wish to use simpler PAP therapy devices. One possible solution is Provent, a sleep apnea treatment device developed by researchers at Stanford University. Provent features two small, disposable devices with air filters that fit into both nostrils. Provent does not feature a generator or connective hose. This device has been approved by the FDA, and is clinically proven to reduce the symptoms of sleep apnea.
Individuals who are interested in Provent or other alternative sleep apnea treatments should consult their doctor for more information.
Optimal pillow loft: People with sleep apnea often snore more when they sleep on their backs with their heads elevated. For this reason, doctors often encourage people with sleep apnea to sleep on their side, which provides better air circulation and reduces the risk of snoring. However, some people simply cannot sleep in this position — and for these individuals, optimizing the ‘loft’ (or thickness) of their pillow may be a suitable alternative.
‘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 pinpointing the best pillow loft, it’s important to keep the following factors in mind:
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 enable sleepers to customize the angle of their sleep surface by inclining or declining the head; some models offer adjustable feet, as well. Inclining the head at certain angles can help cut down on snoring for people with CSA. Some adjustable beds also come equipped with ‘anti-snore’ presets that automatically adjust the head of the bed to these angles. Depending on the model, an adjustable bed may have manual, remote, or app-based controls.
Most adjustable beds support at least 600 pounds — and some models support as much as 800 pounds. This makes them suitable for most adults and their sleep partners. Adjustable beds normally cost at least $1,000, and some are priced at $3,000 or higher. For more information, please visit our Adjustable Bed Reviews page.