CPAP Machine FAQs

CPAP (pronounced "see-pap")

  • Short for "continuous positive airway pressure"
  • Positive airway pressure therapy is the most effective noninvasive treatment for obstructive sleep apnea (OSA)

How does CPAP therapy work?

Air is pushed from the flow generator through the tubing and mask. The air then passes through the nose and into the throat, where the slight pressure keeps the upper airway open.

CPAP treatment involves a CPAP machine, which has three main parts:

  • A mask or other device that fits over your nose or your nose and mouth. Straps keep the mask in place while you're wearing it.
  • A tube that connects the mask to the machine's motor.
  • A motor that blows air into the tube.

Some CPAP machines have other features as well, such as heated humidifiers. CPAP machines are small, lightweight, and fairly quiet. The noise that they make is soft and rhythmic.

CPAP often is the best treatment for obstructive sleep apnea. Sleep apnea is a common disorder that causes pauses in breathing or shallow breaths while you sleep. As a result, not enough air reaches your lungs.

The low air pressure does not interfere with breathing, though some people need a few nights to get used to the sensation of positive airflow.

Successful CPAP users report improvements in:

  • Vitality and motivation
  • Job performance
  • Mood
  • Sexual drive and performance
  • Alertness while driving
  • Quality of life
  • Quality of sleep

A failure to use CPAP therapy may increase your risk for conditions linked to untreated OSA:

  • Hypertension (OSA increases your risk of hypertension by up to five times)
  • Stroke
  • Congestive heart failure (CHF)


  • Short for "automatic positive airway pressure"
  • Device used in the treatment of obstructive sleep apnea (OSA)
  • Automatically adjusts, on a breath-by-breath basis, to deliver the minimum pressure needed to keep the upper airway open during sleep. This allows the device provide you with your ideal pressure over the entire night.
  • Tend to be more advanced and contain more features than CPAP devices.
  • May also be known as:
    • Auto-adjusting CPAP
    • Auto-titrating CPAP
    • Self-adjusting CPAP
    • Auto PAP
    • Automatic CPAP
    • Auto

Why might I prefer an APAP machine?

  • Some CPAP users find it more pleasant to breath with APAP than with CPAP because the pressure automatically changes as needed to deliver the minimal pressure needed. With a CPAP the pressure is set at the highest necessary pressure to keep the airway open, even though the high pressure may only be needed a fraction of the time. APAP’s offer a great option for folks who are in a physician directed weight loss program or have changing pressure needs. Many APAP’s have been shown to maintain a lower average pressure since they only deliver what you need when you need it.


Bilevel devices can provide therapy:

  • For people with Obstructive Sleep Apnea (OSA) if they have found continuous positive airway pressure (CPAP) therapy too difficult.
  • Provide noninvasive positive pressure ventilation (NPPV) for people with respiratory disorders or other forms of Sleep-Disordered Breathing (SDB).

Bilevel therapy works by delivering two different levels of positive air pressure:

  • A higher level of pressure when you breathe in.
  • A lower level of pressure when you breathe out.

Although both are non-invasive, Bilevel and CPAP therapy differ in two significant ways:

  1. Bilevel devices deliver two levels of air pressure that are set to coincide with the patient's inspiratory and expiratory efforts
  2. Bilevel therapy can be used to treat conditions other than sleep apnea (OSA) and is the first line of treatment for a wide-range of respiratory disorders

Frequently Treated Conditions with Bilevel

Physicians may use bilevel therapy to treat a broad range of conditions, including:

  • Nocturnal hypoventilation
  • Respiratory insufficiency
  • Neuromuscular disease
  • Respiratory failure
  • Chest wall deformity
  • Chronic obstructive pulmonary disease (COPD)
  • ALS or Lou Gehrig's disease
  • OSA*

*Bilevel therapy is not typically prescribed for OSA patients; however, OSA patients who require high treatment pressures or have another respiratory condition are often candidates for bilevel therapy.

Types of Bilevel

  • Bilevel
  • Auto Bilevel
  • Bilevel ST
  • Adaptive Servo Ventilation

May also be known as:

  • BiPAP
  • Auto BiPAP
  • BiPAP ST
  • BiPAP Auto SV
  • VPAP (variable positive airway pressure)
  • Auto VPAP
  • VPAP Adapt SV

Manufacturer Warranties

APAP, Bi-level, and CPAP machines all come with a warranty from the manufacturer. If you experience a malfunction with your equipment, please contact our office to determine if it is still covered by the warranty. You will also want to ask for the RMA number. Decisions regarding warranties are solely the manufacturer’s responsibility. You as the customer will be responsible for sending the equipment to our office, and the necessary replacements and repairs can take up to four weeks. We may be able to provide you with a rental machine during the time that you are without your equipment for repairs.

Water damage and misuse are not protected under the manufacturer warranty. If it is determined that these issues caused the malfunction, you can choose to have the machine repaired at your cost or returned to you at no cost. You can also choose to purchase new equipment based off of the list of current prices on the company website.