New APAP User

[jdm2857]

I have used my APAP for two nights now. The first night I kept it on for 4 hours, and the second night for 7.

It is set for 5-20 cm H20 with EPR off. I am surprised at how quiet the machine is. I woke up several times each night and
made adjustments and went back to sleep.

I am having difficulty understanding the results data I am getting via the machine's screen. (cpap.com did not have the software in stock,
but I should have it soon.)

Last night's data:

Pressure: 11.2
Leak 0.1 l/s
AHI: 22.8
AI: 12.3
HI: 10.5

The numbers from the first night were similar.

I don't understand why my AHI is so high. Shouldn't an APAP go to higher pressure to reduce this?
As you can probably guess from thest numbers, I don't feel any better on the APAP than without it.

Any suggestions would be greatly appreciated.

[klockemy]

I will take a stab at this, but I am sure our more senior members will elaborate....

From the looks of it, your leaks are great, but your AHI is still WAY too high. With it having a range of 5-20, it's taking too long to get to the pressure needed to stop the events. Since last night was an average of 11cm. I would set the range to like 9-15cm and see how that works. If it pegs out at 15 for most of the night, you might need to move your range up again.

Kevin

[BeanMeScot]

Whatever your titrated pressure was, you want the bottom number to be no more than 2 less than that. As klockemy said, the machine is taking too long to get to the correct pressure to respond to your apnea. You want it to be fairly close to it.

[Gerald]

JDM....

What Kevin is suggesting is the way to go. Right now, your machine is set to a spread that won't allow good performance.

Also....I realize that your leak data looks OK, but double check for leaks. Reducing all leaks to almost zero is the key to good therapy.

Gerald

[Wulfman]

I have used my APAP for two nights now. The first night I kept it on for 4 hours, and the second night for 7.

It is set for 5-20 cm H20 with EPR off. I am surprised at how quiet the machine is. I woke up several times each night and made adjustments and went back to sleep.

I am having difficulty understanding the results data I am getting via the machine's screen. (cpap.com did not have the software in stock, but I should have it soon.)

Last night's data:

Pressure: 11.2
Leak 0.1 l/s
AHI: 22.8
AI: 12.3
HI: 10.5

The numbers from the first night were similar.

I don't understand why my AHI is so high. Shouldn't an APAP go to higher pressure to reduce this?
As you can probably guess from thest numbers, I don't feel any better on the APAP than without it.

Any suggestions would be greatly appreciated.

To answer your last question.......
Your pressure range is set too wide open. Your starting pressure is too low to prevent the vast majority of events. APAPs/Autos move their pressures slowly (except for leaks, snores and flow limitations), testing and waiting to see if that pressure change stopped the events before moving upwards again. It will not go from 5 cm. to 10 cm in one quick pressure change. That type of pressure change would undoubtedly wake you right up. Your machine IS raising the pressure as noted by your 95% pressure number of 11.2, however it's doing it AFTER too many events have occurred.

Do you have a prescription for a CPAP pressure? If so, set your minimum pressure to THAT pressure. From the 95% pressure number you have listed (11.2), you would probably be better off to just set your minimum pressure at 10 cm. and see what the numbers look like after about a week.

Den

[jdm2857]

I forgot to mention that although I had a diagnostic PSG (AHI=43), I opted to forgo a titration PSG and use an APAP instead to save money. (The one PSG I did have was free via a research study, but lucky me got randomized to a non-cpap treatment group.) I have been losing weight, so my true AHI may be a bit lower now. It took a bit of looking to find a sleep doctor who would entertain this idea as many believe that APAP is a last resort and will only use standard CPAP on new patients. The practice that I found (at the same major university medical center as the research study) is much more forward thinking (and much less focused on maximizing the number of PSGs that they perform) than the other practices that I contacted. The doctor I had was great, and they were able to test-fit masks right in the office (although they did it sitting up.)

What exactly does the pressure number represent? I assumed that it was the maximum pressure that the machine reached, but from the responses posted, it obviously is not.

The Clinical Quick Setup Guide supplied with the machine documents the menus, but does not discuss the meaning of any of the settings or results numbers. Is this documented somewhere else?

I will increase the minimum pressure setting on my machine tonight, and post again tomorrow.

Thanks for all your help.

[klockemy]

The pressure is measured in centimeters of water (or commonly referred to as cm/H2O or just cm) using a manometer. If you search the forums, using the search bar at the top, you can actually find easy to follow instructions (with pictures) on how to construct one and how the principle works. The pressure that you listed is the least and most pressure that your machine will tritate to 4cms to 20cm. When we say that your machine is set to 'wide open' ranges, that is because 4cm is the least your machine will provide and 20cm is the most. In most people 4cms almost seems suffocating and by concensus, is rarely prescribed. Most people are around 6-7 or higher. Since your machine got up to 11cms last night and you were still having events, it seems like your machine didn't have time to go higher to stop the events; hence the reason we suggested you increase your range. The smaller the range, the more efficient your machine is in treating events; however, you have to be really close to your 'sweet spot' before it does any good, otherwise your machine will just strain at it's limits, trying to stop events. I hope this helps explain the process.

Kevin

[jdm2857]

Being cautious, I only changed the pressure settings to min 8 max 20.

Last nights results:

Pressure: 11.6
Leak 0.62 l/s
AHI: 18.5
AI: 9.7
HI: 8.8

So, AHI is a bit better, but leak is worse, and the overall pressure is just a bit higher.

I will bump up the minimum pressure a bit more tonight.

[JoyD.]

.
jdm,

First Welcome I'm so glad you discovered this wonderful CPAPTalk Community!

Your AutoPAP will titrate you nicely. You are on the right track, moving your lower pressure up in increments. Most of us find that it is important to stay at each pressure change for at least 4 days before moving it again, since there are nightly variations. You don't want to miss it when you find your "sweet spot".

As you get closer to your "true pressure", you may find that it ends up being a bit higher that it looks to be now. That is what I experienced. When I started increasing my lower pressure of 8 (the doc had it set 8-20), my 90% pressure said 11. After a couple months of moving my lower pressure upward slowly and reading my software daily that 90% pressure also increased. [I believe that your machine uses 95% rather than 90%]. Now my 90& pressure is either 13 or 14 . . . at my "sweet spot" set at 12-17. (The reason I backed my upper pressure downward from 20 to 17, is that I never saw my pressure get over 16 when chasing events.)

Along with the process of titrating myself carefully, I also watched my leak graphs closely and worked very hard to get a near-straight line. That was done experimenting with different masks, chin straps and taping, and I found that I got consistently low AHI results with a chin strap AND tape (thats not everyone's experience, but it is for a lot of us.) That's another reason you need to go slowly with your titration . . . there are other variables occurring nightly that you need to address. Ask questions so we can help with those things.

I'm convinced that there is a LOT to this thing called "acclimation" to CPAP. I'm now at five months . . . and the past two weeks my AHI's are consistently UNDER 2. I'm not doing anything differently than I did a month or two ago. Everything is just settling in for me. [I'm one of the lucky ones who "felt alert during the day" after my first night on CPAP, even when my numbers were bad. The fact that I had Severe OSA and was FINALLY--after maybe decades--getting improved oxygen to my brain probably helped!]

I have also learned that good sleep hygiene is essential for optimal CPAP results Having been a Night Owl all my life, NOW I'm getting to bed no later than 11:30 pm and make sure I sleep 8 hours. (I'm retired, so if I were working I'd go to bed earlier to get those 8 hours!) I also find that a 3 mg sublingual Melatonin tablet is important for me at bedtime, and to avoid napping after the noon hour. (In the beginning I slept in long hours to "catch up" on my sleep debt.)

So . . . it takes some months to find out these things about yourself as you seek to optimize your therapy. Hey, no one can better optimize our "daily treatment" than we can ourselves (with the help of our forum friends)!

Way to go, jdm, you're ON YOUR WAY!

Joy

PS - To those dealing with multiple diseases in addition to OSA / or Complicated SDB. . . I understand and empathize with you that you have a more difficult road to tow! My heart goes out to you, and I'm rooting for each one of you that you will find the help and answers you need to find relief and success with your therapy!

[jdm2857]

Well, I now have 2 more night's data with the pressures set to 8/20, and haven't seen an improvement.

Here are the numbers:
...........................Sat............Sun
Pressure (95%)..........11.6...........12.0
Leak (l/s).................0.20...........0.44
AHI.......................18.7...........22.8
AI..........................9.2.............8.1
HI..........................9.5...........14.7

On Saturday I switched from the Medium to the Large pillows, and since it is not a problem I will continue with the Large.

Having read studies online where APAP typically has resulted in AHIs under 10 on the first night when set wide open, I am getting a bit discouraged.

I will up the pressure to 9/20 tonight and see if that affects anything. The software (which was out of stock when I ordered) shipped today, so I should have the ability to
get detailed data before too long.

I would appreciate any further advice.