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+--- Thread: Do I need an ASV machine? (/Thread-Do-I-need-an-ASV-machine)
Do I need an ASV machine? - masonmiller407 - 11-15-2019
Hi everyone,
I was so happy I found this forum. Reading all the posts here has educated me about sleep apnea more than my sleep doctor. Anyway, last month I got 2 at-home sleep studies from 2 different hospitals (just to compare the results). Both results came back positive for severe sleep apnea (AHI 30.9/hr), and they both show all of the events were Obstructive Apneas + Hupopneas, 0 Central Apneas. So I got the BiPAP ResMed AirSense 10 and have been sleeping with it for almost a month now. The treated AHI I got from OSCAR has been around 2-3, sometime 4. So I guess the treatment is working. However, in the event flags panel, 90% of the events were flagged as Central Apnea on pretty much all nights over the past 30 days.
Do I have CA? Should I get an ASV machine instead (cost is not an issue)? Why didn't the two at-home sleep studies detect CA? Should I go check for any heart condition to be safe to use ASV? I'm a 29-year-old healthy and fit male. Thanks a lot in advance!
[attachment=17076][attachment=17077][attachment=17078]
RE: Do I need an ASV machine? - Gideon - 11-15-2019
Without seeing your sleep tests (full copy), I can't comment on them.
Looking at your charts, let's try an experiment. Set your PS to 1 (PS = 1) and let's see what happens. I'm expecting the numbers of your centrals to significantly drop.
What I THINK is happening:
I take this is a sign that your machine is acting very efficiently. So much so that it is washing the CO2 out of your bloodstream, sound good? I did too, unfortunately it is a 'high' amount of CO2 in the blood that triggers a breath, not a low amount of oxygen. By changing your PS from 4 to 1 as above should demonstrate that this is happening, then we can look at a solution. I just wrote a Wiki article about it here. http://www.apneaboard.com/wiki/index.php/Treatment-Emergent_Central_Apnea
RE: Do I need an ASV machine? - masonmiller407 - 11-15-2019
(11-15-2019, 02:25 PM)bonjour Wrote: Without seeing your sleep tests (full copy), I can't comment on them.
Looking at your charts, let's try an experiment. Set your PS to 1 (PS = 1) and let's see what happens. I'm expecting the numbers of your centrals to significantly drop.
What I THINK is happening:
I take this is a sign that your machine is acting very efficiently. So much so that it is washing the CO2 out of your bloodstream, sound good? I did too, unfortunately it is a 'high' amount of CO2 in the blood that triggers a breath, not a low amount of oxygen. By changing your PS from 4 to 1 as above should demonstrate that this is happening, then we can look at a solution. I just wrote a Wiki article about it here. http://www.apneaboard.com/wiki/index.php/Treatment-Emergent_Central_Apnea
Hi bonjour,
Thanks for the reply and the awesome wiki. I attached the sleep study result here. Please take a look if you can.
I'll try changing PS to 1 to see how it goes. My current machine is Auto BiPAP, which means EPAP and IPAP are auto-adjusted during the night, but PS is constant. Can I use an ASV machine as an Auto BiPAP with Auto PS? I read in the ASV manual that this machine can auto-adjust PS throughout the night. Is there an option to turn off ASV feature if I don't need it. That way I don't have to worry about adjusting PS and let the machine handle it. To be honest, I could get this ASV machine for cheap through my insurance, so I need to make the decision before the year ends.
[attachment=17089][attachment=17090]
RE: Do I need an ASV machine? - Gideon - 11-15-2019
(11-15-2019, 05:41 PM)masonmiller407 Wrote:You cannot use an ASV as an auto BiLevel because the algorithm is different. You could use it somewhat as a fixed biLevel but that IMHO would be for 'emergency' use, not regular use.(11-15-2019, 02:25 PM)bonjour Wrote: Without seeing your sleep tests (full copy), I can't comment on them.
Looking at your charts, let's try an experiment. Set your PS to 1 (PS = 1) and let's see what happens. I'm expecting the numbers of your centrals to significantly drop.
What I THINK is happening:
I take this is a sign that your machine is acting very efficiently. So much so that it is washing the CO2 out of your bloodstream, sound good? I did too, unfortunately it is a 'high' amount of CO2 in the blood that triggers a breath, not a low amount of oxygen. By changing your PS from 4 to 1 as above should demonstrate that this is happening, then we can look at a solution. I just wrote a Wiki article about it here. http://www.apneaboard.com/wiki/index.php/Treatment-Emergent_Central_Apnea
Hi bonjour,
Thanks for the reply and the awesome wiki. I attached the sleep study result here. Please take a look if you can.
I'll try changing PS to 1 to see how it goes. My current machine is Auto BiPAP, which means EPAP and IPAP are auto-adjusted during the night, but PS is constant. Can I use an ASV machine as an Auto BiPAP with Auto PS? I read in the ASV manual that this machine can auto-adjust PS throughout the night. Is there an option to turn off ASV feature if I don't need it. That way I don't have to worry about adjusting PS and let the machine handle it. To be honest, I could get this ASV machine for cheap through my insurance, so I need to make the decision before the year ends.
Sleep study, a diagnostic study, shows no Centrals and is missing the summary. No centrals means that any centrals later are likely Treatment-Emergent Centrals. Your Obstructive events are over 30 seconds average duration. This is longer than normal even though your oxygen didn't dip real low.
RE: Do I need an ASV machine? - SarcasticDave94 - 11-15-2019
In my opinion, as I didn't see any central apnea present, 1) ASV is not needed nor justified and 2) you'd probably need at the most a ResMed VAuto.
RE: Do I need an ASV machine? - Sleeprider - 11-15-2019
Your Aircurve 10 Vauto is an amazing machine, and I'm surprised that it was prescribed with straight obstructive apnea. I agree with the suggestions you have received so far, and we usually see a significant reduction of CA events with less pressure support. I have also found that if there is pressure support being used, that a trigger sensitivity of "high" rather than medium, can by itself reduce CA events. Just though I'd put it out there in case you need something beyond the suggestions above.
RE: Do I need an ASV machine? - jaswilliams - 11-16-2019
(11-15-2019, 10:25 PM)Sleeprider Wrote: Your Aircurve 10 Vauto is an amazing machine, and I'm surprised that it was prescribed with straight obstructive apnea. I agree with the suggestions you have received so far, and we usually see a significant reduction of CA events with less pressure support. I have also found that if there is pressure support being used, that a trigger sensitivity of "high" rather than medium, can by itself reduce CA events. Just though I'd put it out there in case you need something beyond the suggestions above.
I think the VAuto was bought out of pocket. I agree that all that is needed here is to reduce the Pressure Support. There is no need of an ASV.