How Does ResMed APAP distinguish OSA vs. CSA?
Hello all, first post here, please bear with me.
I have just started using a PAP device for the first time, specifically a ResMed AirSense 10, for the previous two nights.
The only previous sleep test I'd taken that could detect apneas (as well as distinguish between obstructive and central apneas) was a Snap Diagnostics at-home test taken ~2 months ago, which included a chest belt to monitor abdominal motion. It showed mild-to-moderate OSA, with apneas *overwhelmingly* dominated by obstructive rather than central (25 OSA events to 1 CSA event in a 6 hr period).
Using the AirSense 10, I was in APAP mode with max/min pressures set to 9 and 4 cmH2O, respectively (first night), and 8 and 4 cmH2O, respectively (second night). EPR was set to reduce expiratory pressure by 1 cmH2O.
Both the AirSense 10-generated sleep reports and the OSCAR outputs indicated that OSA's had been eliminated *completely* on both nights, but also reported a substantial number of CSA's (21 first night, 12 second night). While the overall AHI for both nights was certainly acceptable (3.91 and 2.46, resp.), I was surprised to see such a large number of CSA's, considering that the Snap test detected only 1 in an entire night.
So, my first question is: Could the use of this APAP device have *immediately* induced so-called Treatment-Emergent CSA's?
And my second question is: How can this device distinguish between OSA's and CSA's in any case? That is, it would seem that the only information actually available on the machine end is pressure and flow rate vs. time... I can see how that would allow detection of a cessation in breathing, but how could it detect an unsuccessful attempt to breathe, without any information about abdominal motion?
Thanks so much for any info!
I have just started using a PAP device for the first time, specifically a ResMed AirSense 10, for the previous two nights.
The only previous sleep test I'd taken that could detect apneas (as well as distinguish between obstructive and central apneas) was a Snap Diagnostics at-home test taken ~2 months ago, which included a chest belt to monitor abdominal motion. It showed mild-to-moderate OSA, with apneas *overwhelmingly* dominated by obstructive rather than central (25 OSA events to 1 CSA event in a 6 hr period).
Using the AirSense 10, I was in APAP mode with max/min pressures set to 9 and 4 cmH2O, respectively (first night), and 8 and 4 cmH2O, respectively (second night). EPR was set to reduce expiratory pressure by 1 cmH2O.
Both the AirSense 10-generated sleep reports and the OSCAR outputs indicated that OSA's had been eliminated *completely* on both nights, but also reported a substantial number of CSA's (21 first night, 12 second night). While the overall AHI for both nights was certainly acceptable (3.91 and 2.46, resp.), I was surprised to see such a large number of CSA's, considering that the Snap test detected only 1 in an entire night.
So, my first question is: Could the use of this APAP device have *immediately* induced so-called Treatment-Emergent CSA's?
And my second question is: How can this device distinguish between OSA's and CSA's in any case? That is, it would seem that the only information actually available on the machine end is pressure and flow rate vs. time... I can see how that would allow detection of a cessation in breathing, but how could it detect an unsuccessful attempt to breathe, without any information about abdominal motion?
Thanks so much for any info!
