AHI Going Up With New BiPap Machine

[Stewart194]

I've had my new BiPap machine for almost a week, and my AHI is higher now than it was with the regular APAP machine the sleep clinic loaned me. I don't get it. I had some mask leaks that I think I have figured out now. I thought that was attributing to this, but last night I had very few leaks and had an AHI of 22.9!

With the APAP, I eventually began to see AHI's of 2.5, .83. 2.6,1.4, etc. Since getting my new BiPap last week it has been 3.5 & 3.2 with a leaky mask, & 11.7, 9.3, 8.4, and 22.9 after I got the leaks squared away.

The sleep tech dialed in my pressure numbers, which is 14/10. She said that after she found them I had about 3.5 hours left of the study, and during that time I didn't have any apneas with those numbers.

Why am I having such crazy numbers now? I know the AHI's that SleepyHead is reporting are legit because I feel a lot worse than I did with the APAP machine also. Is it time for me to start tweaking the settings myself? Should I try the "Auto" BiPap setting?

Thanks in advance!

Matt

[Krelvin]

Hard to read your chart and it is missing info on the left to explain why you don't seen to be using Bilevel. Look at https://sleep.tnet.com/resources/sleepyhead/shorganize for how to organize and share clear large versions of your data which are easy to read.

[Stewart194]

I thought I had the chart in the order you guys like to see? Here is a screenshot with the left side correct. (I think)

[JDS74]

Hi Stewart:

Your report mentions a large number of large leaks - 9 events.

But the most interesting thing is the number if central apneas and obstructive apneas.
Some folks have centrals show up with higher pressures so that may be part of the problem.

What was the loaner machine? Was it really an auto machine? That would account for the low OSA rate then and the high number now if somehow this machine is in bi-level mode and not in bi-level auto mode.

Do you know what the pressure support setting is? ResMed machines are not as flexible in this area when the pressure support is close to the whole pressure range.

[Stewart194]

Thanks for the reply! The loaner machine was a Respironics System One 60 Series APAP. I tried it in Auto mode but got the best results when I set the minimum pressure to 13. I think it was still in Auto mode, but the pressure couldn't go below 13. The pressure would spike to 15 at times but never went above that. In fact it stayed at 13.5 most of the time.

As far as the leaks go, I've tried 3 different masks, with and without liners, and I think this current mask is going to be as good as it gets unfortunately. It seals well actually, until I sleep on my side. I mostly sleep on my back anyway, but when I do sleep on my side, my pillow pushes my mask over a bit and then the sound of the leak wakes me up and I correct it by laying on my back again.

I'm not sure what the pressure support setting is. How can I find out?

[Stewart194]

Also, why does the pressure settings in SleepyHead show

PS -340282346638528859811704183484516925440.0 over 340282346638528859811704183484516925440.0--340282346638528859811704183484516925440.0 (cmH2O)

Is that a clue that my new machine isn't set correctly?

[Julie]

I can't tell you much about numbers, but I have 2 suggestions. One is to do whatever possible not to sleep on your back as it provokes a lot more apneas. The other would be to try a soft cervical collar that will keep your head off your chest, opening up your airway a lot better, and also help keep your mouth closed (if that's an issue leakwise).

[Stewart194]

Thanks Julie! Unfortunately I am a habitual back sleeper. I'll look into the collar suggestion. I'm willing to try anything to figure this out.

[palerider]

I thought I had the chart in the order you guys like to see? Here is a screenshot with the left side correct. (I think)

if you compare what you posted, CAREFULLY, with the example that Krelvin pointed you to, you can find the differences, and change them.

[palerider]

Also, why does the pressure settings in SleepyHead show

PS -340282346638528859811704183484516925440.0 over 340282346638528859811704183484516925440.0--340282346638528859811704183484516925440.0 (cmH2O)

Is that a clue that my new machine isn't set correctly?

no, it's because that machine came out after that version of sleepyhead, and so there are a few new fields that sleepyhead is guessing at, just ignore that bit.

[Stewart194]

OK thanks Palerider. How is this? Am I missing anything now?

[palerider]

OK thanks Palerider. How is this? Am I missing anything now?

that's pretty good, I need to suggest to krelvin that he remove the mask pressure and by pressure...

you could take the bottom two off and have everything that's needed normally, and that'll give a bit more space for the others.

I'd try auto, and reducing your pressure support.

if 13.5 was working on the loaner, then I have to wonder what orifice the tech pulled 14/10 out of.

btw, your pressure support is 4, 14-10.

you might want to try vauto mode, minepap 12, maxipap 25, ps 2 see where that takes you.

that's raising your base pressure to 12, closer to where you were (13.5) instead of where you are now (10) and lowering the ps, which is kinda high and may be contributing to the centrals you're having.

[Stewart194]

Thanks! They didn't ask me what was working for me on the loaner, or ask to see any graphs. In fact they had never heard of SleepyHead or the liners from padacheek. During the first overnight stay, they basically determined that a regular CPAP or APAP wouldn't work for me. The doctor recommended that I try a BiLevel and an ASV machine, and scheduled a 2nd overnight study.

During the 2nd study, she started me off with a BiLevel machine. Once she figured out that my settings were 14/10, she said I didn't have any more apneas for the remaining 3.5 hours and she never tried the ASV. Not sure if that would have been better or not.

Either way, at this rate, I would have been better off with the APAP. I will see if I can figure out how to change those settings that you recommended tonight! THANKS! I REALLY appreciate it. I'm ready to dial this thing in and finally get some proper rest.

BUT, I think I remember the sleep study people saying that I shouldn't mess with the settings on a BiLevel machine. Something about how they are a lot different than a CPAP or APAP and that I could possibly harm myself somehow if the settings weren't correct? Have you ever heard of that?

[Stewart194]

[kaiasgram]

I think I remember the sleep study people saying that I shouldn't mess with the settings on a BiLevel machine. Something about how they are a lot different than a CPAP or APAP and that I could possibly harm myself somehow if the settings weren't correct? Have you ever heard of that?

All the time ! They also say that about regular CPAP and APAP machines.

It is true that higher pressures can cause central apneas for some people, which is a question we have about your current settings. But as you can see, this can happen no matter who is setting the pressure(s)! You cannot do any more harm to yourself than the techs can do to you unless you are just willy nilly messing with the pressure settings. With the software and your willingness to monitor, you can adjust settings as well as the techs can.

The challenge now is to see if you can reduce those centrals while keeping obstructives at bay. You're getting good help with that.

It is possible that you did ok for the 3.5 hours they watched you at the lab, but it's not the optimal pressure for ongoing therapy. Possibly not even the best machine. I think you said the possibility of needing an ASV machine was mentioned, but for now you can keep working with this machine to see if some improvement can happen.