CPAP and BiPAP-which one is right for you? When buying a CPAP machine online, research is important. Continuous positive airway pressure (CPAP) machine is the most commonly prescribed device for the treatment of obstructive sleep apnea. The CPAP machine provides a constant air flow with a fixed suction pressure setting to keep the airway open. The bilevel machine (BiPAP) offers two pressure settings: one pressure for inhalation and a lower pressure for exhalation. BiPAP machines are suitable for more serious sleep disorders, such as central or complex sleep apnea, or for users who cannot tolerate CPAP because they provide breathing support. Common confusing words for BiPAP: B-PAP, Bye-level Buy your CPAP or bilevel ventilator online and have confidence in resxoy. Contact one of our on-site sleep experts to help you find the right machine or ask us about our prescription options.