apap, flow limitations, weight loss...

[bryan512]

a year ago when I had my last sleep study done, they prescribed me an APAP at 16-20 I think? I don't have insurance, so no APAP was gunna happen. I set my machine to 16, and just lived with that. In the past year, I've lost 60 pounds (yea me!) but my sleep was getting worse. My guess was the pressure was too much and I didn't need that much anymore. I finally got an APAP so I set it for a WIDE range, 4 to 20 It doesn't didn't adjust to above 8 for about a week, so I set it for 8 to 20, figuring if it only went up to 8 in the past, maybe it would stay at 8, but I left the other end high so if anything changed, it could go higher. I still wake up (completely) 3 times a night, and generally only sleep 6 hours a night. cutting my pressure cut way down on central apneas, obstructive apneas don't seem that bad (I've been told EVERYONE stops breathing while sleeping occasionally, one or two times a night, but not a lot or enough to wake them... true or not, I donno), anyways, my flow limit events went for 0 on the CPAP (never had one, I donno if that's something CPAP doesn't do?) and my hypopnea's have gone up.

Does setting the APAP low end too low make it less effective? I mean shouldn't it just rise if it needs to? What about setting the high end too high? My AHI is generally less than 3, which is nothing compared to some of you, but yet I'm always tired, increasingly so, to the point of almost falling asleep several times though out the day. (And this didn't just start with the pressure changes and the APAP,(I think I said this earlier?) but this is the whole reason I started playing with the pressures. and they have improved slightly, my AHI was between 3 and 4 typically... but I mostly slept through the night...

[avi123]

[quote="bryan512"]

Does setting the APAP low end too low make it less effective?

Yes, it does. If you don't have the exact therapeutic pressures then the machine would not treat you at all.

I mean shouldn't it just rise if it needs to?

No, see here how I set the min and max pressures on my APAP:



I set the pressures so that the pressure graph is confined nicely within the two limit lines of maximum and minimum set pressures. The pressure graph is close but does not hug any of these lines. This lets the machine work more efficiently. It does not allow the machine to raise the pressure suddenly for no reason and give me central events. Also, by having the minimum pressure close to the actual therapeutic pressure, the machine does not waste time responding.

[kteague]

...cutting my pressure cut way down on central apneas, obstructive apneas don't seem that bad... Does setting the APAP low end too low make it less effective? I mean shouldn't it just rise if it needs to? What about setting the high end too high? My AHI is generally less than 3, which is nothing compared to some of you, but yet I'm always tired, increasingly so, to the point of almost falling asleep several times though out the day.

I'm guessing some of the data hounds on here would love to see some of your reports. Besides number of events, duration matters too. If your events are long, maybe it would be helpful to have your doctor order a recording oximeter for a couple nights to see how your oxygen is looking. BTW, an autopap will increase if it sees trouble coming but it is a calculated incremental increase, so when the lower end of a pressure range is far below your therapeutic pressure, it can take a long time to get to where it needs to be. By then it may need to open an obstruction instead of prevent one.

Once you get this sorted out and working for you, if you are still symptomatic, you may want to start ruling out other possible contributors. Some meds interfere with sleep continuity, and there are other sleep disorders like limb movements that can mess with sleep. It can be a process of elimination. Good luck.

[Julie]

What kind of mask are you wearing?

[Pugsy]

Usually if the minimum pressure is too low the AHI will be too high. If your AHI is less than 3 most of the time...then the minimum seems to be working.

It would be helpful to see a couple of typical daily detailed reports to see what kind of events and look for potential clustering of the events.
You know it's possible that the variations in pressure are disturbing your sleep quality at some low level. After all you were on fixed pressure for quite some time. Some people can sleep through some big changes in pressure and never know it (that would be me) until they look at a report the next day but others find that even the slightest change in pressure can impact sleep quality.

The maximum pressure setting...that becomes a moot point if you never go there or even close to it. If the machine could go to 100 but never went past 10...it wouldn't matter what the maximum was set at if it never comes close.
Now sometimes the machine might come close and raise the pressure in response to snores or flow limitations that it can't quite get a handle on...or maybe aerophagia rears its ugly head...but normally if the machine never goes over 8 cm...it doesn't matter if you set the max at 10 or 20 or somewhere in between. If it doesn't go there...ever...it doesn't matter. If it goes there sporadically and causes a problem like wake ups or aerophagia then yes, limit the maximum.

[BryanC]

ok, wow, apparently I got a lot of my info wrong. lemme try again (my horrible sleep is messing with my mind!) My last sleep study said APAP 16-18. I set my CPAP to 16, and I was having a lot of clear airway apneas. I dropped it to 13, and the clear apneas almost went completely away, my AHI dropped for about a month. Then back up a little but still averaging less (in my opinion). recently I got the APAP, set i;
t 4 to 20 for 4 days. it never went above 8 so I raised the lower to 8. First night at 8 it went up to 12. Last night it went up only to 11. It generally dropped back to 8 though, and appears every time I woke up it was at 9, and usually there's no event that causes me to wake up. (well, ok, yesterday apparently I had an 88 second obstructive apnea event... seems kinda impossible to me?)

Here's my AHI data from the last year or so...(I hope I did this right, cause I can't see 'em even when I preview the message..)


Last night


a closer look at last night


My mask is a swift FX nasal pillow. I think I do a lot of mouth breathing though.

(side note on the nasal pillow... I had the head gear that wraps around the head, and it always had big leaks through out the night as I slept, but when I got this new machine, I also got some new 'head gear' which is basically 2 rubber band like things that wrap from the mask, around your ear, then back to the mask, then same on the other side. my leaks have gone to almost nothing...)

so, I donno what I'm asking or saying anymore. But, isn't an AHI of less than 2 suppose to be NORMAL, as in non-apnea? I guess I'll set min back to 13 and see how that does...

[Pugsy]

When you do your image of your detailed report could you go back to the detail tab on the left instead of the Events tab?
That way we can easily see your AHI breakdown.
On the graphs on the right...don't zoom in. Zoomed in we can't see the pressure line or the leak line graphs in total.

[Pugsy]

AHI less than 2.0...when someone is using the cpap machine means that the machine is doing its job.
AHI less than 2.0 when someone isn't using any sort of cpap machine...means no apnea.
If you are thinking that you may not have sleep apnea anymore with the weight loss....maybe..maybe not. But for right now all that nice low AHI means is that the machine is doing a great job.

[BryanC]

like that?

[Pugsy]

Yes, thank you.

What is that stuff up by the 130 line on the flow rate graph...those red things? Snores?
Snores aren't normally seen like that. They normally are a full line through the flow rate line. Looks like the increase in pressure seems to go along with them though. Did you or do you sleep on your back? Is it possible that you were on your back during the time with the snores and increased pressure during that middle session?

How come the fragmented sleep sessions? Any particular reason?

[BryanC]

the stuff by the 130 line, if I'm understanding you correctly, is all the even flags. though 114 of them are 'pressure pulses' which I'm not really sure what they are, well, why they are. as for sleeping on my back, I go to sleep on my side, but do roll to my back sometimes when sleeping. And the fragmented sleeping, I have no clue. just has (at least for the last year, longer I'm fairly sure) always been the way I sleep. I hate it, and no sleeping pill seems to make any difference.

[Pugsy]

Pressure pulses are little puffs of air that the machine puts out to help it decide if the event it senses is happening is central in nature or obstructive in nature. We can see them even without an event flag because whatever it sensed was going on didn't materialize into a full grown event that warrants a flag. Maybe it didn't last the full 10 seconds.

Your flow rate graph doesn't look like my flow rate graph on my PR S1...but I had forgotten about pressure pulses.
Normally the snores or hyponeas or OAs or CAs will have the line go through the black line vertically and not be stuck at the top. Not sure why yours is doing that.
Which SleepyHead version are you using?

Does it take you long to go back to sleep when you wake up and we see a break in the therapy line?

[BryanC]

ok, I changed some settings, maybe this view works better for you?

[BryanC]

oh, and as for going back to sleep, it varies, some nights it'll happen right away, some nights I lay there awake for hours, other times, I'm simply not 'tired' so I get for an hour or so then go back to bed. lately (per doctors orders) I take a sleeping pill (ambien) an hour before I go to bed, and one when I wake up at night (taking 2 when I go to sleep I only did once. Apparently that made me sleep walk, and I went back to bed and didn't put my mask on, so after the first 'wake' I have no record of anything.) and generally I stop drinking caffeine around 3pm, and stop eating around 9 (when going to bed around 10)

[Pugsy]

Yep, that view looks like what I am used to seeing.

The data in terms of AHI and events looks good on paper. What doesn't look good is the fragmented sleep with large blocks of time not being asleep. That's gotta mess with your sleep quality and sleep architecture. Kinda hard to fix if you don't know what is causing it though.

The middle segment....it's obviously much more exciting than the first or last sleep segment. So something changed during that middle segment time frame and my first suspect would be supine sleeping became involved.
If you normally see the first wake period about 90 minutes or so after sleep onset then you may be waking up during REM stage sleep for some reason.

I think that this is where Robysue could some in and discuss the insomnia issues. She does that so much better than me.

How are you feeling in general?
How would you rate your sleep quality as it is now?
How many times do you wake during the night and not turn the machine off?
Do you lay in bed using the machine for any prolonged period of time?....Edit...never mind this one as I see that you do.

Congratulations on your weight loss. If just looking at the first and last segments...you perhaps don't need that 8 cm minimum...maybe could go a bit lower but the middle segment is a bit worrisome as we don't know what caused that change.
I don't think it really matters what your maximum is set at because the machine doesn't seem to want to go any further than it does unless you are experiencing aerophagia issues.
Have you tried cpap mode or apap mode with tight range to see if that helps you sleep a bit better with less wake ups?
Some people are super sensitive to the least little pressure change and when that happens cpap mode or apap mode with a tight 1 cm range might work better.