CPAP vs BIPAP vs APAP Machines

A person who is diagnosed with sleep apnea has a few of choices for treatment of the disorder. Next to mouth devices, treatment via machine is the most utilized method, where air is pushed into the lungs.

There are three types of machines used in treatment; CPAP, APAP, and BiPAP. These flow generators are devices approved by the FDA and require a prescription from a licensed physician in order to obtain one. Studies show that consistent use of a positive airway pressure (PAP) machine has proven to have a decrease in apnea events and prevent more sleep apnea complications. There is no cure for sleep apnea, however, PAP therapy in combination with a good sleep apnea pillow greatly reduces the risks associated with it. All PAP machines work by blowing pressurized air into an airway. The machines vary in their method of delivery. Which PAP device is the best choice to use in treating your sleep apnea can be determined by your physician and your individual health needs.

Did you know? PAP is the most effective and most widely used method for treating obstructive sleep apnea.


A CPAP machine is the most basic of the machines prescribed. It is the least expensive, and usually covered by insurance for this reason and that most people perform well with it. Standing for “continuous positive airway pressure” this machine is the treatment most often prescribed to sleep apnea patients. A CPAP provides a single constant and continuous flow of oxygen into the airway that a person repeatedly inhales and exhales during sleep. Patients diagnosed with low to mild obstructive sleep apnea will benefit from the use of CPAP machines.

Positive benefits

  • The CPAP is the most cost effective machine to use in the treatment of sleep apnea.
  • Newer machines may be technologically advanced enough where they can detect a person’s breathing and adjust pressure output as needed.
  • While it can be uncomfortable, once familiar, the CPAP can provide a much better quality nights sleep, lessesing apnea events for the user.
  • The prevention of snoring therefore aids in the lowering of blood pressure, which in turn helps prevent other heart related issues such as heart attacks or strokes.
  • There is also a more pleasant sleeping experience for the apnea patient’s bed partner due to less disruptions and apnea events.
  • Providing a better quality of sleep / sleeping through the night – having sleep apnea often contributes to to daytime sleepiness due to the interruptions of snoring, gasping, awakenings and other side effects, using a CPAP combats this.
  • Lower stress levels

Negative drawbacks

  • Comfort level: the biggest drawback to a CPAP machine is getting used to breathing via this method. It can be troublesome and leave some people feeling claustrophobic upon exhaling; which is generally the most difficult adjustment to make in wearing a CPAP mask. This challenge results in the disuse of the machine and rendering its capabilities null and void. The machine only works to curtail sleep apnea through regular daily use. Manufacturers have tried to help these circumstances by adjusting the air pressure the CPAP machine puts out via internal sensors
  • The pressure setting is fixed
  • Skin irritations from wearing a mask can cause rashes, abrasions, or skin allergies
  • Dry mouth can stem from an improperly fitted mask or the continual blowing of air into the mouth
  • CPAP machines do not allow for weight fluctuations in the user; the pressure settings can therefore become too weak or too strong
  • Feelings of bloating and gas that can be caused by incorrect air pressure settings
  • The low pressure settings will be of no use if one has been drinking alcohol


APAP, or AutoPap; is another automatic continuous positive airway pressure machine. Unlike the basic flow CPAP however, the APAP has two pressure settings consisting of both a high and low pressure range to vary the delivery of air based on its measuring of the individuals inhalation needs during sleep. This range is pre-set and determined by the physician who prescribed the machine. The settings automatically adjust during the night. Inhalation needs are based on any number of factors that can cause apnea events and hinder or block the airway during sleep. These factors can include:

  • Sleeping position (back, side, or stomach)
  • Seasonal allergies
  • Colds
  • Other underlying nasal conditions
  • Drinking alcohol
  • Taking prescribed sedative medication or even over the counter cold and flu meds

APAP machines, when programmed properly, will provide the correct pressure for inhalation during any and all events. It is a proactive machine as opposed to a reactive one like the CPAP. It can detect airway issues early and begin to adjust accordingly. An APAP machine has the ability to shut this feature off and simply be used in CPAP mode, allowing for more flexibility in treatments. Patients with low to moderate apnea can utilize APAP machines; this means they experience many changes in their breathing as opposed to those who have a pattern of continuous apnea events. Additionally, APAP machines benefit restless sleepers, those who toss and turn during the night.

Positive benefits

  • The biggest positive for the APAP is having ab auto adjust mode for pressure levels
    • The pressure levels can adjust based on sleep positions
    • Likewise, the levels can adjust based on changes such as colds or seasonal allergies
  • The comfort level is increased during high pressure apnea events
  • APAP machines compensate for weight loss by adjusting air pressure settings depending on weight loss or gain
  • APAP machine setting can accommodate for mild alcohol consumption before bedtime; as drinking can contribute to changes in breathing

Negative drawbacks

  • An APAP is more expensive than a CPAP
  • People can still find the exhalation aspect uncomfortable
  • While the machine can adjust for various changes, these changes may be gradual or slow and cause awakenings leading to a downgrade in sleep quality
  • An APAP is not a good match for people with certain health conditions like obesity or heart disease


The least commonly used machine, the BiPAP, or BiLevel, differs from its counterpoints in that this flow device delivers two seperate pressures; one for inhalation and one for exhalation. The BiPAP is more complex than a regular CPAP machine and works similar to a ventilator. It is more costly and usually reserved for those with severe or central sleep apnea or with special needs. A BiPap can be used when awake in addition to sleeping; this will depend on your health providers instructions.

Who can benefit from using a BiPAP machine? If you suffer from one of the following, a BiPap may be for you:

  • Parkinson’s Disease or ALS
  • Patients who have tried to use a CPAP and failed
  • Pneumonia
  • COPD (obstructive pulmonary disorder, a group of lung diseases that blocks the airways)
  • Asthma patients
  • Obesity hypoventilation syndrome, where a person’s weight contributes to their poor breathing
  • Congestive heart failure, where the blood isn’t pumping properly to the heart
  • Those with prescriptions from their doctor to set their machines for low oxygen levels or high pressure settings

Positive benefits

  • The BiPAP is very effective in treating those with severe apnea or other health disorders
  • The machine’s pressure can be alternated between inhalation and exhalation, making it comfortable for the user, especially upon exhalation where the pressure on a BiPap lowers

Negative drawbacks

Typically the BiPap is safe to use, with a low risk of complications or infections. Most issues with a BiPap stem from an improperly fitted mask. Age, weight, and health history may have a negative effect on BiPap use. Speaking with your healthcare provider could present solutions to some of these problems, such as a leaking mask or nasal dryness.

Other issues to consider may include:

  • The BiPAP is more costly than either the CPAP or APAP
  • Providing proof of use to insurance companies of another PAP machine prior to receiving approval of a BiPAP
  • Failure using a CPAP or APAP
  • Bloating
  • Eye irritation
  • Sinus problems
  • Central sleep apnea can develop where obstructive sleep apnea was only present before.

People with very poor breathing, such as problems swallowing or reduced consciousness levels will not benefit from using a BiPap. In extreme cases such as these, medical interventions could be necessary. These might include inserting a mechanical tube in the throat or undergoing a tracheotomy, where an airway hole is made in the windpipe. Occasionally, a person’s breathing may improve from use of the BiPap where they will no longer need it and choose to treat their apnea with another machine or interventions.

Note: The device prescribed is dependant on the type of sleep apnea you have along with its severity and any other health conditions present affecting your sleep.

Among other factors, the type of machine you use is determined by the severity of the sleep apnea you are diagnosed with. For those with obstructive sleep apnea, the basic CPAP or APAP machine is a good choice. For those with central sleep apnea or other underlying health issues, a BiLevel is the more appropriate machine.

Maintaining good quality sleep in order to be productive during the day is essential. Losing a night’s rest can result in an inability to function properly. Forgetfulness, irritability, headaches, daytime sleepiness, and trouble paying attention are all side effects of sleep apnea disorder, to say nothing of the health concerns that sleep deprivation can cause. No matter which therapy device is chosen to treat apnea, regular use will contribute to a general improvement in overall well being.