[CPAP] Adjusting for flow limitations

[jane2911]

Hi! First time posting. Have already seen lots of great advice here so wanted to see if there were any suggestions for my settings (particularly flow limitations). I recently switched to "for her" mode and it has been extremely helpful. 

- 31 yo female

- 5'9, 160 lbs

- Home test through Lofta, so not super comprehensive. My AHI was 3.8 (normal) and my RDI was 21.1. O2 nadir 79%. 

I'm not sure if I have UARS or sleep apnea but I do know is that when my therapy stats are good, I feel like a new person. 

I breathe through my mouth, so its possible these are just the best my settings will get. 

I last night I switched my EPR from 3 back to 2 bc of the centrals from the night before (I think I read something about that here!)

[PeaceLoveAndPizza]

There are few knobs left to twist on the Autoset models. You already have “for her” mode turned on and are using the maximum pressure support. You have a good AHI and no real leaks. There is not much left to manage flow limitations from a machine perspective. You could play with pressure settings, higher or lower pressures may help some, but it may cause other issues.

With your AHI being in a good place, time to look at sleep hygiene. 

• Are you using a flat or CPAP pillow? 
  
• Are you chin-tucking?
  
• Do you have a smart watch with sleep stage reporting?
  

There are things you can do like using a CPAP specific pillow or soft cervical collar. I do not think it will help much, but it may be worth a try. 

The main thing to consider is how you feel. It sounds like the therapy you are getting is working, but do you feel you could do better? If not, then you can continue as is and ignore the flow limitations until they impact sleep quality. If so, then you need to consider the options of trying to tweak what you have or move to a different machine like a bilevel.

In the end, you would likely need a bilevel e.g. ResMed AirCurve 10 Vauto to manage the flow limitations. Being able to add more pressure support would make a big difference in sleep quality. You would also have options to manage the IPAP to EPAP and EPAP to IPAP sensitivities, which helps significantly with CA’s. Note that you are managing UARS, not curing it. It will still be present, but the machine will manage most of the effect.

It is something worth chatting with your sleep team about. Worst case you can possibly find a used Vauto at a fair price on Facebook Marketplace.

[Sleeprider]

Your CAI was very low with EPR 3 and we would expect those to diminish in time. Clearly, therapy was much better with EPR 3, with fewer therapy stops, lower overall pressure lower flow low limitation (0.04 vs 0.10). My recommendation would be to return to EPR 3 and increase minimum pressure to 7.0 or 8.0. Your median pressure was 8.5.

[jane2911]

Thank you so much for reviewing, I will do that tonight!

[jane2911]

Your CAI was very low with EPR 3 and we would expect those to diminish in time.  Clearly, therapy was much better with EPR 3, with fewer therapy stops, lower overall pressure lower flow low limitation (0.04 vs 0.10).  My recommendation would be to return to EPR 3 and increase minimum pressure to 7.0 or 8.0.  Your median pressure was 8.5.

sorry didn't know how to @ this post but I appreciate this advice and will plan to change it tonight

[jane2911]

There are few knobs left to twist on the Autoset models. You already have “for her” mode turned on and are using the maximum pressure support. You have a good AHI and no real leaks. There is not much left to manage flow limitations from a machine perspective. You could play with pressure settings, higher or lower pressures may help some, but it may cause other issues.

With your AHI being in a good place, time to look at sleep hygiene. 

• Are you using a flat or CPAP pillow? 
  
• Are you chin-tucking?
  
• Do you have a smart watch with sleep stage reporting?
  

There are things you can do like using a CPAP specific pillow or soft cervical collar. I do not think it will help much, but it may be worth a try. 

The main thing to consider is how you feel. It sounds like the therapy you are getting is working, but do you feel you could do better? If not, then you can continue as is and ignore the flow limitations until they impact sleep quality. If so, then you need to consider the options of trying to tweak what you have or move to a different machine like a bilevel.

In the end, you would likely need a bilevel e.g. ResMed AirCurve 10 Vauto to manage the flow limitations. Being able to add more pressure support would make a big difference in sleep quality. You would also have options to manage the IPAP to EPAP and EPAP to IPAP sensitivities, which helps significantly with CA’s. Note that you are managing UARS, not curing it. It will still be present, but the machine will manage most of the effect.

It is something worth chatting with your sleep team about. Worst case you can possibly find a used Vauto at a fair price on Facebook Marketplace.

I really appreciate your advice!

-  I'm using a flat pillow that has a cut out so that my mask can fit when I lie on my side
- Had never heard of chin tucking. I wouldn't be surprised if I am. I'll look into the collar. 
- Good to know about the Vauto. My insurance is not great this year but perhaps another year/on marketplace.
- [edit] I have an apple watch that I've used inconsistently (not since december). It does not have 02, though. I'll try wearing it tonight and see what I find.

Thank you again!

[Sleeprider]

Don't worry about the @sleeprider. I don't get notices like that, but I do follow the threads that I participate in.

[jane2911]

Don't worry about the @sleeprider. I don't get notices like that, but I do follow the threads that I participate in.

good to know. appreciate your support!

[PeaceLoveAndPizza]

Follow SleepRider’s recommendation for pressure changes. It likely will not reduce the flow limitations, but should help with sleep quality.

Flow limitations, as well as arousals and UARS, are interesting beasties to chase. There is a trade-off on managing them vs going after quality sleep. Just because you can reduce flow limitations does not mean you will sleep better, it just means you have managed flow limitations. Same for arousals. 

Feeling rested, regardless what your machine or OSCAR reports, is our goal. We all get caught up chasing numbers, but it does not mean we had quality sleep. Quite a conundrum at times.

[apnea505]

The Apple Watch really has been useless for helping with breathing issues at night. You really need a device that measures oxygen and heart rate continuously.