CPAP (Continuous Positive Airway Pressure)
A therapy device delivering a single fixed air pressure through a mask to keep the upper airway open during sleep. The first-line treatment for obstructive sleep apnea.
What Is CPAP (Continuous Positive Airway Pressure)?
Continuous Positive Airway Pressure (CPAP) is the most common treatment for obstructive sleep apnea. It delivers a single, constant air pressure through a mask worn during sleep. This positive pressure acts as a pneumatic splint, keeping the upper airway open by counteracting the negative inspiratory pressure that would otherwise pull the airway walls inward.
CPAP uses one fixed pressure for both inspiration and expiration. The prescribed pressure is determined through a titration study (either in-lab or via auto-titrating CPAP over several nights). Most modern CPAP devices, such as the ResMed AirSense 10 and 11, can operate in either fixed-pressure CPAP mode or auto-adjusting (APAP/AutoSet) mode.
While CPAP is highly effective at preventing complete airway collapse, it may not fully address flow limitation in all users. Some people require BiPAP (bilevel) therapy for additional pressure support during inspiration, or adjustments to EPR (Expiratory Pressure Relief) settings. AirwayLab helps identify whether residual flow limitation persists on current CPAP settings.
How AirwayLab Measures This
AirwayLab reads CPAP pressure settings from the STR.edf file on the SD card and compares prescribed pressure with delivered pressure calculated from the BRP.edf flow and pressure waveforms. This helps verify whether the machine is delivering the intended therapy.
Try it with your dataFrequently Asked Questions
How does CPAP work?
CPAP delivers constant positive air pressure through a mask during sleep. This pressure acts as a pneumatic splint, keeping the upper airway open by counteracting the negative pressure created during inspiration that would otherwise pull the airway walls inward and cause obstruction.
What is the difference between CPAP and APAP?
CPAP delivers one fixed pressure. APAP (also called AutoSet on ResMed devices) automatically adjusts pressure within a set range based on detected breathing events, increasing pressure when it detects flow limitation or apneas and decreasing when breathing is stable.
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Medical Disclaimer
AirwayLab is not a medical device and is not FDA-cleared or CE-marked. It is provided for educational and informational purposes only. The analysis results should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult qualified healthcare providers regarding your sleep therapy and any changes to PAP settings.