The CPAP machine stops this condition by applying a stream of compressed air through a tube to a full face or nasal mask, splinting the airway (to keep it open under air pressure) so that breathing becomes possible without obstructions, thus reducing and preventing apneas and hypopneas. This has the added benefit of reducing or eliminating the extremely loud snoring that often accompanies sleep apnea.
The CPAP machine blows air to a prescribed pressure (also called valued force). A sleep doctor determines the necessary pressure after performing a sleep study at night (polysomnography) in a specialized center and supervised by a professional technician. The rated pressure is the air pressure in which most (if not all) apneas and hypopneas have been avoided, and measured in centimeters of water (cm H2O). The pressure required by the majority of patients with sleep apnea ranges from 6 to 14 cm H2O. A typical CPAP machine can deliver pressures of between 4 and 20 cm H2O. More specialized units can supply pressures up to 25 or 30 cm H2O.
Types of CPAP
There are a few different types of CPAP. The term CPAP is a general term used to describe all kinds of Positive Airway Pressure (PAP) therapy, but it is also a specific type of PAP. CPAP is the most common type of PAP and consists of a constant pressure of air blowing to keep the airways open.
Another common type of PAP is one that uses two different pressures, a higher pressure during inhalation and a lower pressure during exhalation. This type is called BiPAP or two-level. BiPAP most commonly used for patients who have difficulty exhaling against high CPAP pressure. It can also apply to certain types of sleep apnea or other breathing problems.
Sometimes a BiPAP machine is used with a backup rate to help patients breathe when they have a certain type of sleep apnea called central sleep apnea. The backup rate tells the machine to switch between inspiratory pressure and expiratory pressure at a rate set to encourage breathing.
A new type of CPAP called Servo Ventilation can also used. This is a highly specialized machine that self-adjusts to keep patients breathing at or above a specific target level. This type of machine used for patients with central sleep apnea or Cheyne-Stokes breathing (a common and strange type of breathing characterized by alternating periods of apnea and hyperpnea).
The last type of PAP is called AutoPap. This is a specific type of CPAP machine that auto-adjusts the CPAP level to resolve apneas. This type of machine is useful for patients who have worse apnea at different stages of sleep or in various positions (such as when they sleep on their backs) and have difficulty tolerating higher CPAP pressures. These machines can also use as a diagnostic tool to see if the pressure of a patient at home should be more significant.
Today’s CPAP machines are microscopic and quiet. There are several different brands of CPAP machines. The doctor can help you determine the best machine for your needs.
There are also many different types of CPAP masks available. The dream center technicians will work with you to find the mask that works best for you during your dream study. You can also switch to a different mask if you are having problems with your current mask. This should do within 30 days of receiving your mask if it is possible for your medical equipment provider to change your mask without charge.