General target for AHI?

I am a recovering apneic, having been a free nocturnal breather for too long now and am back on CPAP for only about 2 weeks. However, this if the first time ever that I have had a machine I can actually monitor. (M Series Pro) For the last 11 days of full compliance (6+ hrs/night) I have an average AHI of 7.4 with avg OAI 6.3 and avg HI 1.1.

Is this the best I should expect to achieve? (Assuming good mask fit, etc.)

I realize there is a big item missing in my comment here---the sleep study. I do not have a copy of the current study so I don't know how things went and am currently relying 100% on the sleep tech's and sleep doc's prescription, which was "9 +/- 1 cm H20". Up or down a centimeter seems like a fair bit of wiggle room. My sleep DME is a "take your machine home and don't even think about looking at the index info" kind of company. They refused to sell me a card reader and the software, so had to acquire that online.

Would appreciate any feedback for a once-again-newbie. I have no desire to tinker with my pressure right now, but would like to understand if I should be talking with the sleep doc if I can't improve my AHI any further.

Generally you want your AHI under 5. AHI is made up by the SUM of OA +HI divided by time/60.

If your OAI is higher than 5 it may mean you need a pressure increase. Get OA down and HI should take care of itself. I would try 10cm.

Pressure gets too high where you cannot fall asleep, use the Ramp feature.

I agree with Snoredog that raising the pressure would probably reduce the number of obstructive apneas you're still having. Since your Rx stated 9 +/- 1 cm H2O, I'd go on and raise the pressure to 10 cm, if it were me; I'm no doctor. I'd even raise my pressure to 11 or 12 if need be.

As Snoredog said, an AHI under "5" is generally considered ok.

PeaceSleeper, you mentioned "Assuming good mask fit, etc." You're on the right track to think about things that could affect an AHI and make it higher even if 9 cm would otherwise be treating you fine and preventing most obstructives. Mask leaks are definitely something to check on.

The "etc" that I'd be looking into for sure is whether you have treatment air leaking out your mouth in the form of air puffs, and whether you might be mouth breathing during the complete relaxation of sleep.

You have the software, so examine the leak rate graph for the past several nights. If you see a lot of jagged up/down movements of the leak line on each night's "Daily Details" graph you might want to do some detective work on where the leaks are coming from -- mask, mouth, or maybe both.

Thank you Snoredog and rested gal for your quick responses. Let me add when I was last on BiPAP about 5 years ago, I was titrated at 10 and 5, which correlates well with your comments.

Also, I was puzzling over the leak data---because there is direct correlation with leaks and OA events, however the timeline resolution is not adequate for me to see which came first. Is it fair to speculate that the leak occured first, followed by an OA? That makes logical sense, and tells me I have a lot of mask/pillow testing and adjustment work to do again.

I also saw another possible correlation---a higher OA event index when using a ComfortLite 2 setup versus a regular nasal ComfortClassic mask. Perhaps I had the ComfortLite 2 "squished" or something that limited air flow and caused the jump in OA index---more than double what I see with a nasal mask. Or maybe it means nasal pillows are not for me and I should stick with a nasal mask?

Great stuff. How do people do this without the ability to read their machine's data file? I'm trying 10 cm tonight and see how the OA goes overnight. I'm much more optimistic that CPAP this time around is going to work and I will get back some of my life. And I'm sure the DME will be washing their hands of me if I tell them I'm tweaking my own pressure. (Within the prescription......)

PeaceSleeper wrote:How do people do this without the ability to read their machine's data file? I'm trying 10 cm tonight and see how the OA goes overnight. I'm much more optimistic that CPAP this time around is going to work and I will get back some of my life. And I'm sure the DME will be washing their hands of me if I tell them I'm tweaking my own pressure.

The lucky ones end up finding the forums......particularly this one. The unlucky ones either struggle or give up.

This is YOUR therapy.....not theirs. You're the one who has to sleep with this stuff every night.
Why should they care if you're improving your therapy? FUGM!

Den

PeaceSleeper wrote: I have an average AHI of 7.4 with avg OAI 6.3 and avg HI 1.1.

Since your OAI is much larger than HI, I suspect you are having central appneas. Therefore it's a good idea to consult your physician about your pressure setting.

Thanks for all of the comments. Please keep them coming if you have other insights.

Ergin wrote:Since your OAI is much larger than HI, I suspect you are having central appneas. Therefore it's a good idea to consult your physician about your pressure setting.

I'm not a doctor. I agree it's never a bad idea to consult with your doctor. My purely non-medical opinion...I don't think there's any reason whatsoever to suspect the obstructive apneas showing up on your data are really "central apneas." I think there's every reason to suspect one of the following things (not in any particular order) are letting actual obstructive apneas happen:

A. leaks (especially mouth air leaks/mouth breathing) might be interefering with treatment. Treatment air escaping into the bedroom from massive mask or mouth leaks isn't going where it's needed to keep the throat open.

B. the prescribed pressure might simply not be enough.

C. untreated or undertreated GERD (acid reflux) might be causing tissue inside the throat to be swollen and rigid. CPAP treatment is designed to push aside soft tissue. It's kind'a hard to push back irritated rigid tissue. If the throat is getting nightly acid baths, raising the pressure is not the answer - treating the GERD is.

If you decide to continue with the CL-2, you might want to read up on the "garbage can tie" fix. You may...or may not....need it....depending on your facial structure. Oldgearhead can help you with this modification.

Also, I'd consider lubricating the nares with Lanolin (it's available at drugstores....for breastfeeding moms). The Lanolin makes the nasal pillows fit better....and helps prevent air leaks by improving the seal.

Finally, you might also want to experiment with an Aura mask. For me, it's working a little better than the CL-2. Like the CL-2, the Aura has a hose that connects at the top of your head.....and easily suspends from an arm mounted above you.

PeaceSleeper wrote: <..snip..>
I'm trying 10 cm tonight and see how the OA goes overnight.
<..snip..>

One thing to keep in mind. Don't go by one night's data. Even looking at my own results, with no apparent / intentional changes, my AHI may be 1-2 one night and 4-5 the next.

It's usually a good idea to make one change at a time and see how it goes for several days. Preferably a week.

On top of that, I'll also warn: Use the numbers as a guide only. Don't forget to factor in how you feel.

Good luck, and of course, if you have any questions, the wealth of knowledge here seems to be un-ending.

-craig

Craig-Tx wrote:One thing to keep in mind. Don't go by one night's data. Even looking at my own results, with no apparent / intentional changes, my AHI may be 1-2 one night and 4-5 the next.

It's usually a good idea to make one change at a time and see how it goes for several days. Preferably a week.

Excellent advice, Craig!

I understand there is a give and take regarding OSA and GERD. By that I mean they are not necessarily cause-->effect in either order. GERD could cause OSA, by doing things like causing VCD, vocal cord dysfunction, a form of laryngospasm. But treating GERD in this case with PPIs might, or might not be effective long-term. My sleep doc thinks that the OSA could be creating reflux--at the point of high stress apnea. That is an entire forum by itself---as to how to best treat GERD with OSA. However, I'd certainly like to learn more about it!

As I further understand silent reflux, it also creates huge diagnostic challenges since monitoring for reflux activity is not the easiest thing to do. Nasty nasogastric-pH probes or little intra-esophageal radio capsules are different ways to do it, but imagine CPAP titration on top of an NG-pH probe assessment. I would never go to sleep myself. So perhaps night-time PPIs are the best way to minimize the potential impact of GERD on CPAP therapy, or at least to minimize any potential impact to CPAP therapy. The radio transmitter capsules do sound interesting though---except for the part of putting them into your esophagus!

I know my OSA, as I have read with many folks, gets much, much worse in REM sleep. (58 events/hr) The sleep center suggested I had not had any significant REM sleep in months because my brain was trying to protect me from apnea. I don't know if that is true, as my brain is not talking on that matter.

Thanks also for the trend guidance. Makes sense to observe the data for a trend while holding other parameters stable over a reasonable time period, to avoid false conclusions as to cause-effect.