New user - UARS(?) and CA events

[egret]

Hi CPAP nerds - I have a few newbie questions.

I was diagnosed with UARS (low AHI, high RDI) from a WatchPAT home study and prescribed a CPAP with 4-20 cmH20 pressure. Last night was my second night using it and my first night using it with an SD card. My AHI scores were similar for both nights and a lot higher than in my sleep study.

I bought an Airsense 11 with heated tubing and a Dreamwear nasal pillows mask. I set the EPR to 1 and "full night" and climate control to manual.

Here are my questions:

1. I'm having a hard time wearing the mask when the pressure is down around 4 because it feels like I can't breathe, especially if I'm on my side. It feels fine around 5 or 6. Would there be any drawback to me raising the minimum pressure by a few cm? I used the machine for 1.5 hours last night and 5 hours the night before but I feel like I could use it longer if it weren't for the suffocating feeling.

2. I'm getting a lot of either sweat or condensation on my upper lip under the nasal pillow. The machine doesn't think the mask is leaking. Any tips to fix this? Or should I just get used to it?

3. OSCAR seems to think that I'm having a lot of "open airway" events while I sleep. What does this mean? Is there something I can do about them? I've attached screenshots from the whole 90-minute night and zoomed in on some of the flagged events.

Thank you!

   
   

[egret]

I went ahead and raised the min pressure a little bit last night. I didn't have any suffocating feelings and was able to use the machine for the whole night, so that's a plus. And my CA events were shorter - mostly under 40 seconds this time. I think the leaks were a combination of nose and mouth leaks - I remember forgetting to keep my mouth closed a few times and I'm still having a little trouble getting the mask to fit quite right.

More questions -

1. Are there any settings changes that you'd recommend for comfort or for reducing the CA events? I don't know if they are a result of therapy or if I always had them and the sleep study just didn't pick them up.

2. I was thinking of dropping the min pressure by 0.2 at a time until I was back down at the lowest minimum >4 that doesn't feel suffocating. Does that make sense to do? Or is higher just better for everything?

   

[PeaceLoveAndPizza]

You CA’s have some clustering to them, which is likely from chin-tucking. A soft cervical collar and a bit more pressure should get rid of most of them.

Suggest getting a collar (amazon is a good source, I use Caldera Releaf but others like Nimood, but plenty to choose from), and setting your machine to min of 7, max of 20, EPR 3. After a few nights post the chart and we can take it from there. If you have ramp enabled, turn it off as it is doing nothing for your therapy.

Consider setting humidity and tube temp to auto for now. You can fine tune them later as needed.

[egret]

I’m not sure why, but when I set the climate control to auto the CPAP blew HARD (it sounded and felt like a hair dryer) and said I had a leak of 100s of liters even though I couldn’t feel a mask leak. I tried refitting the mask and restarting the machine, but the only thing that made it stop was manually setting the tube temperature.

Is chin tucking an issue for people of all shapes and sizes? I’m thin with a long neck, and I feel like I breath fine when I touch my chin to my chest while I’m awake. But who knows what goes on when I’m asleep haha

[PeaceLoveAndPizza]

Climate and hose temp have nothing to do with pressure. There was something else going on there. You likely had something not fully connected, which was the cause of the high pressure.

Everyone can chin tuck, regardless of height, weight, body structure, or gender.

[egret]

Right - clearly (almost) everyone can physically tuck their chin down - I was trying to ask if chin tucking would cause medium- or long-duration airway obstruction in all shapes/sizes of people since there's a lot of variation in how much neck/chin gets pressed against the trachea when you do that, depending on body shape.

[gainerfull]

1. Raising your minimum pressure is no big deal if it increases comfort and keeps you using your cpap. Given the residual obstructive events I'd probably recommend 7cmH20

2. The condensation is likely from the humidity settings. Change it from auto to 1.

3. Did Watchpat detect any central events during your at-home sleep study? If I were you I'd turn off EPR for the time being as it could be contributing to the massive amounts of central events. Once your body is better adapted to CPAP you can experiment then but seems like your body might be having a hard time stablizing o2 / c02 with the pressure difference (normal).

PeaceLoveAndPizza - please be careful with your recommendations as they are not helpful atm and could lead the OP to making their therapy worse. I know you probably just want to help but you're giving essentially opposite advice.

[PeaceLoveAndPizza]

Yes, chin-tucking can cause all kinds of durations for flow limitations. Many examples of OSCAR reports in the forum with it pointed out. 

I don’t know how much a chin-tuck contributes to some amount of flow limitation, though I have wondered about it. I have noticed as my collars degrade, flow limitations go up from chin-tucking, but have not bothered to analyze it any further.

[Sleeprider]

Egret, UARS is another way of saying "flow limitations", and you have a bunch. Inspiration flow limits reflect a restricted or partially obstructed airway, and it can be seen when you zoom into the flow rate enough to see the shape of the flow. Yours will be flattened or downward sloping. The solution is to use pressure support or in this case EPR to supplement your inhalation breathing effort. You need some setting changes:
Mode: Autoset
Minimum pressure 6.0
Maximum pressure 9.0
EPR: Full-Time
EPR setting: 2
Climate: Manual
Humidity Level: 4
Tube Temp: 80*F (27*C)

This will result in a pressure range of 6.0/4.0 (inhale/exhale) to 9.0/7.0. I'm certain this will lower the 95% flow limitation to nearly zero. There is a possibility it may increase CA events. At this point we would rather resolve the flow limitation/UARS and observe what happens with CA events. It is not unusual to see CA events in new users as they adapt to the improved ventilation, especially with EPR or pressure support. We usually see these events diminish on their own, but there are some other techniques we can use if needed. The purpose of these settings is to see if there are respiratory improvements with the increased EPR. For more information on flow limitation here is a link to our wiki https://www.apneaboard.com/wiki/index.ph...limitation

[egret]

I'm getting some conflicting advice here, so I started with Sleeprider's settings because they sounded like the easiest option.

I increased the EPR to 2 last night, but only ended using the CPAP for 2.5 hours because I woke up with the mask not sitting in my nostrils right and I couldn't troubleshoot it. I think I might buy a p30i mask instead. The nasal pillows on this mask are set farther apart than my nostrils, even with the smallest size, so it takes a lot of fiddling to get them to push air into my airway instead of pushing air into my skin.

I looked back at my watchPAT report, and it said I only had 1 central event out of 84 total events during the study. So I think it makes sense that these ones might be due to therapy. They are getting shorter - on the first night I have card data for I had a bunch of events over 40s, and last night almost all of them were under 30s.

I can't tell if my flow shapes match what the wiki says about flow limitations or not? I've attached some screenshots showing what they have looked like for the last few days if you are willing to take a look. One file has typical breathing, and the other one has breathing during and around my CA events.