ASV (Adaptive Servo-Ventilation)
A specialised PAP mode for complex or treatment-emergent central sleep apnea. Provides variable pressure support that adapts to the breathing pattern in real-time.
What Is ASV (Adaptive Servo-Ventilation)?
Adaptive Servo-Ventilation (ASV) is a specialised PAP therapy mode designed for complex or treatment-emergent central sleep apnea. Unlike CPAP (fixed pressure) or BiPAP (two fixed pressures), ASV continuously monitors the breathing pattern and adapts its pressure support in real-time.
ASV works by providing more pressure support when breathing weakens and less support when breathing is stable. This counteracts the waxing-waning pattern of periodic breathing by stabilising ventilation without over-ventilating (which can worsen central events by driving CO2 too low). The machine essentially acts as a respiratory stabiliser.
Important safety note: ASV is contraindicated in patients with certain types of heart failure (specifically, symptomatic heart failure with reduced ejection fraction, LVEF below 45%). The SERVE-HF trial showed increased mortality in this population. ASV is appropriate for treatment-emergent central apnea, complex sleep apnea, and periodic breathing not related to severe heart failure.
How AirwayLab Measures This
AirwayLab reads ASV settings from STR.edf and analyses the resulting flow patterns. All four analysis engines work with ASV data, though the Periodicity Index is particularly relevant for assessing whether ASV is successfully stabilising periodic breathing patterns.
Try it with your dataFrequently Asked Questions
What is the difference between ASV and BiPAP?
BiPAP delivers two fixed pressures (IPAP and EPAP). ASV continuously adapts its pressure support based on real-time breathing patterns, providing more support when breathing weakens and less when breathing is stable. ASV is specifically designed for central or complex sleep apnea where BiPAP's fixed pressures are insufficient.
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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.