CPAP machines operate using the same core components:
- Airflow generator: The generator is housed in a small box that includes a motorized fan. The generator will pull in air from the room, pressurize it, and deliver it to the user through the mask.
- Connective hose: This component links the generator to the face mask. Most hoses measure up three to six feet in length, depending on the model.
- Humidifier: CPAP machines may feature a built-in or detachable humidifier. This component warms water that is used to humidify the air before it is delivered through the face mask.
- Filter: To prevent dust and other allergens from contaminating the air, CPAP machines feature an air intake filter that can usually be replaced as needed.
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:
- Full face: This mask fits snugly around the nose and mouth, and is designed for people who sleep with their mouths open.
- Nasal: This mask features a smaller design that fits snugly over the nose, but not the mouth. Nasal masks are ideal for people who breathe through their nose while sleeping.
- Nasal cradle: These masks fit beneath the nose, delivering oxygen to both nostrils without fitting over the bridge of the nose.
- Nasal pillow: The least invasive mask option, nasal pillow masks form a seal around each nostril without coming into contact with the upper nose or mouth.
To properly use a CPAP machine, follow this step-by-step process.
1.) Place the machine on a level surface where it isn’t at risk of falling or moving during the night.
2.) Plug the machine into a wall outlet.
3.) If available, insert the chamber humidifier filled with distilled water.
4.) Secure the connective hose that links the generator and the face mask.
5.) Put on the mask and adjust it to a comfortable setting.
6.) Turn on the machine.
7.) Adjust settings as needed during the night.
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.
Pros and Cons of Using a CPAP Machine
Benefits of using a CPAP machine for obstructive sleep apnea include the following:
- Effective treatment: CPAP machines will not cure sleep apnea — at this time, no cure is available — but these devices are considered the most effective treatment method for people with this condition.
- Easy to use: Even with new and advanced CPAP models, these machines are fairly user-friendly and should not present much difficulty in terms of operating and troubleshooting.
- Light and portable: Most CPAP machines weigh less than five pounds, and will easily fit into a suitcase or carry-on for convenient travel use.
- Wide availability: There is a wide range of CPAP machines available today, including different functions and price-points.
Downsides of using a CPAP machine may include the following:
- Noise potential: CPAP machines can be quite noisy. This can disrupt sleep for the user, as well as their sleep partner and — in some cases — people who sleep in adjoining rooms. Some newer models are designed with quieter motors, but noise potential for most PAP machines is fairly high.
- Physical discomfort: PAP masks may cause soreness and stuffiness in the nose, as well as eye irritation.
- Restricted sleep mobility: Due to the connective hose, people who tend to toss and turn while they sleep may find their CPAP machine restrictive. A longer connective hose is recommended for these individuals.
- High price: Although they are usually cheaper than BiPAP machines, most CPAP machines cost at least $200 — and some models are priced at $800 or higher.
Considerations for CPAP Machine Shoppers
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.
CPAP Prescription Requirements
Prescription requirements for CPAP machines are somewhat confusing. In this next section, we’ll answer some of the most common questions about CPAP prescriptions.