ASV ipap range question

Still trying to figure out the mystery of fluctuating Hypopnea's on my ASV machine. I spotted something interesting in the last two days. When ever I see a lot of Blue on my daily report (Ipap Range), I will have a higher AHI level. Below is the night before, and last nights data. The first night I had a 10. Not changing anything last night I had a 3. Both nights were VERY similar with all the rest of the statistics, except as you notice the ipap range was pretty wild the first night, more than last night, hence the higher AHI's?

So my question is what exactly is the difference between ipap and ipap range?
Thanks again for any info.

I had similar reports...similar in that the ASV was cranking up quite high and quite often to fight off the apneas. I figured if the IPAP had to keep spooling up like that all the time, then why not have the IPAP start higher?

So instead of the prescribed 5 (where I had 5 to 20 AHI's), I pushed it to 7 and that knocked my AHI's down to 4 and under consistently (never had a 5 or over again).

Here's my theory: since an apnea is considered as not breathing for 10 or more seconds, then a hypopnea is a partially resolved apnea. Or an apnea that was reduced to hypopnea. Meaning the machine didn't totally clear the apnea within 10 seconds, thus it registers as a hypopnea. I'm sure the machine eventually cleared those, but just not within that 10 second period that qualifies an event as an apnea or hypopnea.

So by boosting IPAP from 5 to 7, I was giving the machine a head start so it was ahead of the game in fighting the apneas. The end result is the machine was able to knock out the apnea completely in 5, 6, 7, 8 seconds instead of 10 or more. Thus, instead of registering as a hypopnea, it didn't register at all.

Just my own observation and theory.

Kody, in addition to what Amerikan noted, you might also want to check the BPM setting. If it is not set for Auto, it's possible it was intervening because it felt you were not breathing frequently enough. The AUTO setting helps encourage normal respiration and will tend to adjust as your breathing changes throughout the night. Just another thing to try.

Hey Ken, good to see you around more, hope your doing well with your machine and 02 set up these days.
Thanks for your input and theory, what you said makes perfect sense. I have played with raising the ipap up by increasing the min epap,and min pressure support. Perhaps I just hadn't found the right combo of those two elements to do the job consistently correctly yet. Funny the sleep Dr. and sleep lab I go to have the opposite theory of keeping the settings wide open,to let the machine handle everything. I don't think that's the best approach though, your theory makes more sense. In any event, last night was another good one under 5 so who knows. I'm beginning to think the biggest variable is just "me", maybe the way I'm breathing from night to night, or the congestion factor that comes and goes plays a part.

Thanks also John for your input, yes the BPM is set to auto, that's the one setting I have left alone.

I noticed when I've also noticed that my AHI and sleep quality suffer quite a bit if I'm congested. Sometimes I use a neti rinse if the congestion is severe (I will boil the water and allow it to cool, or will mix with distilled water, of a lower temperature. Otherwise I will follow the usual directions for the rinse), and it usually helps matters greatly. Others have mentioned humidity levels affecting congestion, which is worth reading up on (and likely varies from person to person).

In my experiences (although I'm still somewhat new to this) I've found: congestion can interfere a bit with sleep/treatment, auto is pretty awesome, it is important to keep notes (especially if tweaking ANYTHING), if one must change any parameters then one should be changed at a time (in order to see what the response will be), and one night is usually not enough to see trends/responses to treatment.

Well, after much thought, and discussion I also decided to try setting BPM to Auto. I had good luck, sleep, few hypopneas, and an AHI in the range of 2.0-3.5 (tested for a week). Will see what the Dr. says when she is in.

Good luck.

Kody wrote:... Funny the sleep Dr. and sleep lab I go to have the opposite theory of keeping the settings wide open,to let the machine handle everything. ...

I think the end result of the titration should depend on the underlying condition.

If you "just" have central sleep apnea, keeping the unit "wide open" would make sense. In that case you would then only need the pressure when you fail to breathe due to a central apnea. Then a low EPAP pressure and high IPAP pressure makes a lot of sense.

If you have obstructive and central sleep apnea, then you would want to limit the EPAP setting. By keeping EPAP higher (to the point that most obstructive apneas are eliminated), you minimize the "seek lower pressure, apnea, move pressure higher" patterns during the night. However, if there is central sleep apnea, then you would still want the IPAP value to be "wide open", since the increase in pressure does not cause additional central apneas.

If you have complex sleep apnea (as the pressure increases the central apneas increase), then you would almost certainly need to limit the IPAP value. You want it high enough to help clear most centrals without triggering more central apneas. The EPAP pressure depends on the needs of the obstructive sleep apnea. If it is minimal, EPAP can be kept low.

The method that you attain those numbers is different (the titration protocol differs) based on the manufacturer. Respironics uses this titration protocol.

At least that is my understanding of the titration methodology. Hope that helps.

Kody wrote:Hey Ken, good to see you around more, hope your doing well with your machine and 02 set up these days.
Thanks for your input and theory, what you said makes perfect sense. I have played with raising the ipap up by increasing the min epap,and min pressure support. Perhaps I just hadn't found the right combo of those two elements to do the job consistently correctly yet. Funny the sleep Dr. and sleep lab I go to have the opposite theory of keeping the settings wide open,to let the machine handle everything. I don't think that's the best approach though, your theory makes more sense. In any event, last night was another good one under 5 so who knows. I'm beginning to think the biggest variable is just "me", maybe the way I'm breathing from night to night, or the congestion factor that comes and goes plays a part.

Doing ok Kody, but still having the slow wake ups. Sometimes I crawl out of bed yawning to the point of tearing my eyes and feeling like i need to go back to sleep. Usually by afternoon I'm able to function. Overall still better but I haven't figured out these rough wakeups. I plan on calling the sleep doc at the VA for some other suggestions.

As for raising the pressures, my original settings were IPAP=5 and EPAP=7. I now have it at IPAP=7 EPAP=7. I found that by raising the EPAP min, my PTB's got worse and I had periodic breathing. So I keep the EPAP lower, sometimes I even go down to 6 or 5. But the higher IPAP took care of almost all the issues.

Good luck!

I have a bad case of apnea since I can't exhale well with asthma. I'm not sure the high settings are good for me and I'm doing better on 17cm max ipap and below I think. a sleep researcher told me to take min epap 8cm but I tried it last night and it was TERRIBLE, I woke up with a little energy after 12 hours but with bad fog today.

anyone else found supplements like phosphitadyl choline/serine that help brain fog? I cured my brain fog for a few weeks but now it's returning.

I tried an auto asv setting with 20cm last night and still am foggy today, it's terrible, but I had a little energy. I think 20cm isn't good, does it really work for people? I'm going to switch to 16.5 and BPM 9, TI 1.5