lowering flow limitation induced higher AHI?

General Discussion on any topic relating to CPAP and/or Sleep Apnea.
1speechpick
Posts: 126
Joined: Wed Jun 09, 2021 12:16 pm

lowering flow limitation induced higher AHI?

Post by 1speechpick » Thu Jun 24, 2021 2:13 pm

I'm trying to fine tune things and would appreciate any suggestions. I have the Resmed Airsense 10 For Her vauto (am using in Cpap mode): pressure 4, ERP 3, humidity 4, air temp 81. Resmed P10 nasal pillow mask.

When using the "size small" nasal pillow with the P10 I had an AHI of 1.08 and flow limitation (.40 95%, .67 max). I subjectively feel like it's a low air flow with the "small" nasal pillow. Leak rate (2.4 95%, 9.6 max).

I tried changing to the "medium" nasal pillow with the P10 mask: flow limitation improved (.08 95%, .17 max), but AHI increased to 7.50. I subjectively felt like I was getting more air and it was more comfortable. Leak rate (3.60 95%, 13.20 max).

*I used the same Resmed settings when I tried both small and medium nasal pillows.

My questions:

]1. Why would lowering the flow limitation induce a higher AHI when using the medium nasal pillow?

2. What can I do to lower the AHI when using the medium nasal pillow?[/b]

Thank you for any suggestions and help! I'm in the USA.
ResMed AirSense 10 For Her with humidifier and heated hose
Resmed Airfit N20


"The best view comes after the hardest climb"

User avatar
palerider
Posts: 30348
Joined: Wed Dec 16, 2009 5:43 pm
Location: Dallas(ish).

Re: lowering flow limitation induced higher AHI?

Post by palerider » Thu Jun 24, 2021 3:32 pm

1speechpick wrote:
Thu Jun 24, 2021 2:13 pm
I'm trying to fine tune things and would appreciate any suggestions. I have the Resmed Airsense 10 For Her vauto
No, you don't, there's no such thing. You either have an "Aircurve 10 VAuto" (which is silver) or you have a "Airsense 10 AutoSet For Her" (Which has vines on the front).
1speechpick wrote:
Thu Jun 24, 2021 2:13 pm
(am using in Cpap mode): pressure 4, ERP 3,
which removes all the benefits of an Autoset, (Or VAuto), also EPR (not ERP) of 3 is only effective when the pressure(or min pressure in an auto mode) is at least 7.
1speechpick wrote:
Thu Jun 24, 2021 2:13 pm
When using the "size small" nasal pillow with the P10 I had an AHI of 1.08 and flow limitation (.40 95%, .67 max). I subjectively feel like it's a low air flow with the "small" nasal pillow. Leak rate (2.4 95%, 9.6 max).

I tried changing to the "medium" nasal pillow with the P10 mask: flow limitation improved (.08 95%, .17 max), but AHI increased to 7.50. I subjectively felt like I was getting more air and it was more comfortable. Leak rate (3.60 95%, 13.20 max).
You can't judge anything by a single night's sleep, sleep varies too much.
1speechpick wrote:
Thu Jun 24, 2021 2:13 pm

]1. Why would lowering the flow limitation induce a higher AHI when using the medium nasal pillow?
It shouldn't.
1speechpick wrote:
Thu Jun 24, 2021 2:13 pm
2. What can I do to lower the AHI when using the medium nasal pillow?[/b]
Put the machine in autoset (or autoset for her) mode with a min pressure of 7 and a max pressure of 20, and let it do it's job.
Get OSCAR and come chat on IRC: #cpaptalk on irc.libera.chat

Accounts to put on the foe list: mper!?, DreamDiver, Geer1, almostadoctor, sleepgeek, ajack, stom, mogy, D.H., They're often post misleading, timewasting stuff.

1speechpick
Posts: 126
Joined: Wed Jun 09, 2021 12:16 pm

Re: lowering flow limitation induced higher AHI?

Post by 1speechpick » Thu Jun 24, 2021 3:46 pm

palerider wrote:
Thu Jun 24, 2021 3:32 pm
1speechpick wrote:
Thu Jun 24, 2021 2:13 pm
I'm trying to fine tune things and would appreciate any suggestions. I have the Resmed Airsense 10 For Her vauto
No, you don't, there's no such thing. You either have an "Aircurve 10 VAuto" (which is silver) or you have a "Airsense 10 AutoSet For Her" (Which has vines on the front).
1speechpick wrote:
Thu Jun 24, 2021 2:13 pm
(am using in Cpap mode): pressure 4, ERP 3,
which removes all the benefits of an Autoset, (Or VAuto), also EPR (not ERP) of 3 is only effective when the pressure(or min pressure in an auto mode) is at least 7.
1speechpick wrote:
Thu Jun 24, 2021 2:13 pm
When using the "size small" nasal pillow with the P10 I had an AHI of 1.08 and flow limitation (.40 95%, .67 max). I subjectively feel like it's a low air flow with the "small" nasal pillow. Leak rate (2.4 95%, 9.6 max).

I tried changing to the "medium" nasal pillow with the P10 mask: flow limitation improved (.08 95%, .17 max), but AHI increased to 7.50. I subjectively felt like I was getting more air and it was more comfortable. Leak rate (3.60 95%, 13.20 max).
You can't judge anything by a single night's sleep, sleep varies too much.
1speechpick wrote:
Thu Jun 24, 2021 2:13 pm

]1. Why would lowering the flow limitation induce a higher AHI when using the medium nasal pillow?
It shouldn't.
1speechpick wrote:
Thu Jun 24, 2021 2:13 pm
2. What can I do to lower the AHI when using the medium nasal pillow?[/b]
Put the machine in autoset (or autoset for her) mode with a min pressure of 7 and a max pressure of 20, and let it do it's job.

Thank you for helping me. I apologize, I am a newbie and just trying to learn. Is a flow limitation of (.40 95%, .67 max) generally too high?
ResMed AirSense 10 For Her with humidifier and heated hose
Resmed Airfit N20


"The best view comes after the hardest climb"

User avatar
palerider
Posts: 30348
Joined: Wed Dec 16, 2009 5:43 pm
Location: Dallas(ish).

Re: lowering flow limitation induced higher AHI?

Post by palerider » Thu Jun 24, 2021 4:08 pm

1speechpick wrote:
Thu Jun 24, 2021 3:46 pm

Thank you for helping me. I apologize, I am a newbie and just trying to learn. Is a flow limitation of (.40 95%, .67 max) generally too high?
Nothing to apologize for, that info is so you can learn.

Post some charts. http://cpaptalk.com/wiki/index.php/Oscar:organize
Get OSCAR and come chat on IRC: #cpaptalk on irc.libera.chat

Accounts to put on the foe list: mper!?, DreamDiver, Geer1, almostadoctor, sleepgeek, ajack, stom, mogy, D.H., They're often post misleading, timewasting stuff.

1speechpick
Posts: 126
Joined: Wed Jun 09, 2021 12:16 pm

Re: lowering flow limitation induced higher AHI?

Post by 1speechpick » Thu Jun 24, 2021 4:31 pm

palerider wrote:
Thu Jun 24, 2021 4:08 pm
1speechpick wrote:
Thu Jun 24, 2021 3:46 pm

Thank you for helping me. I apologize, I am a newbie and just trying to learn. Is a flow limitation of (.40 95%, .67 max) generally too high?
Nothing to apologize for, that info is so you can learn.

Post some charts. http://cpaptalk.com/wiki/index.php/Oscar:organize

I attached a recent example of a low AHI but I think the flow limitation looks too high. However, being a newbie, I'm not sure. Do you think this flow limitation is too high? My sleep is better but not great yet, and I was thinking it could be due to the flow limitation. What are your thoughts?
Attachments
Screen Shot 2021-06-24 at 6.26.44 PM.png
Screen Shot 2021-06-24 at 6.26.44 PM.png (553.76 KiB) Viewed 347 times
ResMed AirSense 10 For Her with humidifier and heated hose
Resmed Airfit N20


"The best view comes after the hardest climb"

User avatar
Julie
Posts: 18984
Joined: Tue Feb 28, 2006 12:58 pm
Location: Canada E.

Re: lowering flow limitation induced higher AHI?

Post by Julie » Thu Jun 24, 2021 6:17 pm

Do you find it comfortable to inhale (or just plain breathe) at a min. of 4?

Most don't, and initially at least raise it to e.g. 6 or 7. Wonder if that would help the flow limit.

User avatar
palerider
Posts: 30348
Joined: Wed Dec 16, 2009 5:43 pm
Location: Dallas(ish).

Re: lowering flow limitation induced higher AHI?

Post by palerider » Thu Jun 24, 2021 9:34 pm

1speechpick wrote:
Thu Jun 24, 2021 4:31 pm
I attached a recent example of a low AHI but I think the flow limitation looks too high. However, being a newbie, I'm not sure. Do you think this flow limitation is too high? My sleep is better but not great yet, and I was thinking it could be due to the flow limitation. What are your thoughts?
Yeah, those are pretty gnarly.

If you put the machine into auto mode (why is it in cpap mode at the lowest possible setting?) it will raise pressure to lower the flow limitations.
Get OSCAR and come chat on IRC: #cpaptalk on irc.libera.chat

Accounts to put on the foe list: mper!?, DreamDiver, Geer1, almostadoctor, sleepgeek, ajack, stom, mogy, D.H., They're often post misleading, timewasting stuff.

User avatar
Miss Emerita
Posts: 2047
Joined: Sun Nov 04, 2018 8:07 pm

Re: lowering flow limitation induced higher AHI?

Post by Miss Emerita » Fri Jun 25, 2021 1:58 pm

EPR can help with flow limitations, and your EPR is set to 3, but you can't get that functionality with your pressure fixed at 4. In addition to following PR's advice, I'd suggest you raise your minimum to 7 so your EPR can do its thing.
ResMed Aircurve VAuto
Bleep mask

Oscar software is available at https://www.sleepfiles.com/OSCAR/

1speechpick
Posts: 126
Joined: Wed Jun 09, 2021 12:16 pm

Re: lowering flow limitation induced higher AHI?

Post by 1speechpick » Fri Jun 25, 2021 2:40 pm

palerider wrote:
Thu Jun 24, 2021 9:34 pm
1speechpick wrote:
Thu Jun 24, 2021 4:31 pm
I attached a recent example of a low AHI but I think the flow limitation looks too high. However, being a newbie, I'm not sure. Do you think this flow limitation is too high? My sleep is better but not great yet, and I was thinking it could be due to the flow limitation. What are your thoughts?
Yeah, those are pretty gnarly.

If you put the machine into auto mode (why is it in cpap mode at the lowest possible setting?) it will raise pressure to lower the flow limitations.

The trend has been that when I set the machine to a higher pressure, it increases the AHI.
ResMed AirSense 10 For Her with humidifier and heated hose
Resmed Airfit N20


"The best view comes after the hardest climb"

1speechpick
Posts: 126
Joined: Wed Jun 09, 2021 12:16 pm

Re: lowering flow limitation induced higher AHI?

Post by 1speechpick » Fri Jun 25, 2021 2:58 pm

Miss Emerita wrote:
Fri Jun 25, 2021 1:58 pm
EPR can help with flow limitations, and your EPR is set to 3, but you can't get that functionality with your pressure fixed at 4. In addition to following PR's advice, I'd suggest you raise your minimum to 7 so your EPR can do its thing.

The trend has been that when I increase the pressure on the machine, the AHI also increases.
ResMed AirSense 10 For Her with humidifier and heated hose
Resmed Airfit N20


"The best view comes after the hardest climb"

User avatar
palerider
Posts: 30348
Joined: Wed Dec 16, 2009 5:43 pm
Location: Dallas(ish).

Re: lowering flow limitation induced higher AHI?

Post by palerider » Fri Jun 25, 2021 10:16 pm

1speechpick wrote:
Fri Jun 25, 2021 2:40 pm
palerider wrote:
Thu Jun 24, 2021 9:34 pm
1speechpick wrote:
Thu Jun 24, 2021 4:31 pm
I attached a recent example of a low AHI but I think the flow limitation looks too high. However, being a newbie, I'm not sure. Do you think this flow limitation is too high? My sleep is better but not great yet, and I was thinking it could be due to the flow limitation. What are your thoughts?
Yeah, those are pretty gnarly.

If you put the machine into auto mode (why is it in cpap mode at the lowest possible setting?) it will raise pressure to lower the flow limitations.

The trend has been that when I set the machine to a higher pressure, it increases the AHI.
That's not how that normally operates.

You can't have it both ways, you want lower flow limitations, you need higher pressure.
Get OSCAR and come chat on IRC: #cpaptalk on irc.libera.chat

Accounts to put on the foe list: mper!?, DreamDiver, Geer1, almostadoctor, sleepgeek, ajack, stom, mogy, D.H., They're often post misleading, timewasting stuff.