Definition - What does bilevel therapy mean?
Bilevel therapy refers to a type of positive airway pressure used to treat obstructive sleep apnea (OSA). As its name implies, a bilevel therapy device delivers two different levels of air pressure. When an individual wearing a bilevel positive airway pressure device inhales, the pressure is higher than when the wearer exhales. This variation in pressure makes it easier for the individual to exhale because it reduces the air pressure resistance otherwise present.
Bilevel therapy may also be referred to as variable positive airway pressure (VPAP) therapy or bilevel positive airway pressure (BiPAP or BPAP) therapy.
SureHire explains bilevel therapy
One of the primary treatments for obstructive sleep apnea is to use a positive airway pressure (PAP) device to deliver a positive flow of air pressure into the airway of the apnea sufferer. This air is delivered through a mask worn by the person while he or she is sleeping. These devices vary in their features — some provide a continuous flow of pressure at a preset level while others provide for several different preset levels of pressure. Another type of PAP device automatically resets or titrates its pressure levels in response to each breath the person takes.
The purpose of these devices is to artificially prop open the wearer’s throat and airways with pressurized air. However, when the wearer of a PAP device exhales, he or she must overcome the force of this positive pressure. This may cause difficulty or discomfort for some PAP users. To reduce this resistance force, a bilevel device will detect when a person exhales and lower the air pressure level during that phase of his or her breathing cycle.