New APAP user, lots of events despite high pressure

[mannsch]

Hello,

I just had a sleep study done about a week ago, with an AHI of 23.2. I am 33 years old, male, with a BMI of around 26.

I immediately went and bought a machine, the ResMed Airsense 10 Autoset. I have now been using it for 4 nights.

The first two nights very pretty bad due to leakage. The first night I had a nasal mask and had lots of leaks through my mouth. The second night I had a full face mask, but a medium size that was way too small.

On the third and fourth nights (last two nights), I had the Airfit F20. I had it set pretty tight and this got rid of almost all leaks.

However, I am concerned about my stats as I still had an AHI of 12.2 and then 10.0 the last two nights.

Here's a screenshot of last night with an AHI of 10.0: https://prnt.sc/otumwl

About half of my events are Clear Airway (CA) events. This seems to be much higher than normal, right? I am a very light sleeper and wake up and move around a lot, but this seems excessive.

I also have obstructive apneas (1.80 AHI) and hypopneas (3.25), despite having my pressure set pretty high at 5-16. I do not see a pattern with regards to pressure and apneas, they seem to occur at both the higher and lower range of my set pressure.

A few questions:

-- What could explain this very high amount of CA events?
-- Should I increase my pressure even further to try to reduce the Obstructive Apnea and Hypopnea events?

Any advice and tips would be greatly appreciated, thanks a lot.

[Pugsy]

Welcome to the forum.

A few questions:

-- What could explain this very high amount of CA events?
-- Should I increase my pressure even further to try to reduce the Obstructive Apnea and Hypopnea events?

The centrals/Clear Airway events could possibly be from the OAs and/or hyponeas causing arousals and if that is the case if we better prevent the OAs the centrals/CAs should reduce.
Go here and watch all the videos. Especially the last one.
http://freecpapadvice.com/sleepyhead-free-software
It wouldn't be impossible for the bulk of all these flagged events to be arousal related and you weren't asleep...all the tossing and turning you remember point to a lot of awake time.

But assuming you were asleep when most of this ugly was flagged in terms of the OAs and hyponeas...more pressure is needed.
It's obvious your machine goes higher and stays up there and wants to go higher but can't.

We can't do much about the centrals right now so lets try reducing the OAs and see what happens with the centrals.
Fix what we can fix and see what is left over.

For sure the max needs to go to 20 and see where the machine wants to go and the minimum needs to be up around 10 to 12 ish.
If it's too uncomfortable making a big jump with that minimum...go with smaller increments and work up. Might get lucky and not need as much as I think you will need.

[mannsch]

Thank you very much for your helpful answer. I will watch the videos you suggested.

It's obvious your machine goes higher and stays up there and wants to go higher but can't.

Agreed. I will try raising the pressure range to 10-20 and possibly 12-20.

Do you think I should disable the pressure Ramp feature? It is currently at 5, but the pressure doesn't bother me much at 10ish so I think I may not need it

[LSAT]

I agree...I was going to post almost the same pressure recommendation.

[Pugsy]

If you are okay with no ramp then just turn it off. It's entirely up to your comfort level if you use it or not.
The machine doesn't flag stuff when in ramp...so stuff can happen and we not know it.
BUT if the ramp time is rather short and you need it to fall asleep...it's not the end of the world to have 10 minutes of no flagging.
I would rather have a short period of time in ramp than have sleep be hard to come by.....gotta get the sleep first before any of this matters.

[zonker]

Hello,

I just had a sleep study done about a week ago, with an AHI of 23.2. I am 33 years old, male, with a BMI of around 26.

I immediately went and bought a machine, the ResMed Airsense 10 Autoset. I have now been using it for 4 nights.

welcome to the zoo! your can do attitude is going to take you far.

and you are being helped by pugsy, one of our best.

good luck!

[mannsch]

Thanks again for the helpful answers, everyone.

Last night I disabled the auto ramp feature and raised the pressure settings from 5-16 to 10-20.

My AHI decreased from 10.1 to 9.14. The decrease mostly came from OA going from 1.80 to 0.80 (from 20 events to 7), while Clear Airway Apneas and Hypopneas were mostly the same.

Here is the screenshot from OSCAR: https://prnt.sc/ou56a1

After falling asleep, the machine fairly quickly ramped up all the way to 20 and stayed there most of the night. The median pressure during the night was 19.30. It never dropped below 15.

All the obstructive apneas occurred at a pressure of between 19 and 20. The hypopneas all happened somewhere between 18 and 20 in pressure.

A few questions:

-- Given that I was getting apneas at the max pressure, does this mean that the max pressure isn't high enough and that I may need a different type of machine (like a Bipap) to get rid of them completely?

-- I woke up with dry mouth a few times which definitely didn't help my sleep. I have read that higher pressure can cause this. Should I perhaps raise the humidity setting? It is currently at 4.

-- Any tips on what to try next?

[Pugsy]

-- Given that I was getting apneas at the max pressure, does this mean that the max pressure isn't high enough and that I may need a different type of machine (like a Bipap) to get rid of them completely?

Yes. Most likely need a machine that can go above 20 cm

I woke up with dry mouth a few times which definitely didn't help my sleep. I have read that higher pressure can cause this. Should I perhaps raise the humidity setting? It is currently at 4.

Dry mouth is usually from mouth breathing and increasing the humidity setting may or may not help all that much but it is worth trying.
I am assuming that you aren't taking medications known to dry out the mouth and you don't have any sort of health problems that could be a factor in the dry mouth.
The humidifier wasn't really designed to help hydrate the oral cavity...it was designed for the smaller nasal cavity.
But it is worth trying more humidity to see if it helps or not.

I don't know what to make of the centrals at this point. I wonder how many of them were related to awake breathing?????
How many times do you think you woke up last night...either from the dry mouth or something else?

[raisedfist]

Have you tried reducing the EPR?

[Miss Emerita]

It might be helpful to see your Flow Limitation graph. Could you include it when you post a chart again? Thanks!

[mannsch]

Dry mouth is usually from mouth breathing and increasing the humidity setting may or may not help all that much but it is worth trying.
I am assuming that you aren't taking medications known to dry out the mouth and you don't have any sort of health problems that could be a factor in the dry mouth.
The humidifier wasn't really designed to help hydrate the oral cavity...it was designed for the smaller nasal cavity.
But it is worth trying more humidity to see if it helps or not.

I don't know what to make of the centrals at this point. I wonder how many of them were related to awake breathing?????
How many times do you think you woke up last night...either from the dry mouth or something else?

I don't take any medication that can cause dry mouth, but I raised my humidity to 5 last night and it seems to have helped a bit. My mouth did get a little dry.

It is definitely possible that I could be waking up so many times, but that I only remember a few of the instances.

Have you tried reducing the EPR?

I only have the EPR set during ramp mode, which I have disabled for the past two nights. Do you think changing it could affect the clear airway apneas?

It might be helpful to see your Flow Limitation graph. Could you include it when you post a chart again? Thanks!

Yes, I will include that. Thanks.

[mannsch]

Here is last night: https://prnt.sc/ouk84f

The AHI is trending down slightly. In the past 4 nights, it has been 12.34 -> 10.01 -> 9.14 -> 8.05

The only thing I changed last night was raising the humidity level from 4 to 5.

Last night I had a lower AHI for obstructive and hypopneas despite the average pressure being significantly lower. Median pressure was 15.78, down from 19.30 the previous night.

[Pugsy]

EPR can sometimes cause centrals in a very small subset of cpap users because it creates a bilevel pressure situation and sometimes bilevel will actually make centrals worse. Not very common at all though and since you were only using it during ramp when you were using it....obviously not the cause of your central apneas.

We don't always remember waking up or arousals from whatever reason.
The hyponeas themselves could be causing arousals that you don't remember. That is why I was suggesting that we try to reduce the hyponeas and see if the centrals reduce at the same time. You are having enough hyponeas to be a problem anyway so they need to be reduced no matter what.

You might go here and watch the videos to see if you can spot awake vs asleep breathing flagging of events.
http://freecpapadvice.com/sleepyhead-free-software

The centrals....if they are real asleep centrals are borderline numerous enough for making the diagnosis of complex sleep apnea caused by cpap pressures (assuming you didn't have them in the same number without cpap therapy). Complex sleep apnea is when you have both a higher number than we want of central apneas and obstructive apneas (hyponeas normally fall into the obstructive category).

So we first try to figure out if they are real asleep flagged centrals...and if they are then we try to figure out if you had them prior to starting cpap therapy or did they pop up after you started cpap.
If they are related to arousals then we try to fix whatever might be causing the arousals.

Finally even if they are real asleep centrals and caused from cpap therapy pressures...sometimes they will go away with a bit of time as the body adjusts. So doctors won't be so quick to put you on a machine that can deal with the centrals anyway. They will watch them to see if they reduce in number on their own or stay up numerous enough to be a problem on not.

We can't really fix real asleep centrals with your current machine. We can sometimes get lucky and fix the cause of the centrals if they are related to arousals/awake breathing flagging if the cause is something obstructive happening to cause the arousal.
That's why I say we try to fix whatever we can fix with the machine settings and see what's left over after the hyponeas (and a few OAs) are dealt with.
It wouldn't be impossible for the pressure increases which would be made to deal with the hyponeas or flow limitations to actually make real centrals worse. So sometimes we have to walk a fine line with the pressure changes and/or allowing the machine to go trying to kill FLs or hyponeas.

You might end up needing a different kind of machine. One that can deal with both obstructive apneas and centrals but at this stage it's too soon to know for sure.
And while I know the number of centrals might seem alarmingly high to you right now...it's really borderline in terms of your earning the central apnea diagnosis for them.

[Pugsy]

Your flow limitation graph is ugly but I have seen worse.
Did you have any nasal congestion last night?
Do you spend much time on your back?

[mannsch]

Thank you very much. I also read that sometimes initial CPAP therapy can lead to central apneas but that it often goes away after a few weeks.

Many of the CAs do show a big change in the breathing pattern before they happen. Is that a sign of them being arousal related?

Here are a few screenshots that zoom in on them:

https://prnt.sc/ouwxzd
https://prnt.sc/ouwze2
https://prnt.sc/ouwzs9

If they don't go down after a few weeks then I will consider switching to a different machine. The best choice for complex sleep apnea is an ASV, right?

Regarding the nasal congestion, yes my nose was very congested that night. My nose often shuts down when I lay down in bed and it can be quite uncomfortable. Although I am able to breathe, it takes more effort than usual.

Here's a screenshot from last night: https://prnt.sc/oux0o0

The AHI was 7.36, which is an improvement. But the clear airway index was 5.11 which is slightly worse than the last 3 nights.

Things I changed were setting the EPR to Full, level 2. Then I also took melatonin before bed, which I didn't do on the previous nights. My nose wasn't nearly as stuffed as it was the night before.

I'm going to buy a nasal spray and see if it can help open my nasal airway before going to bed.