[Diagnosis] Finding the right settings: Hyperventilation in new user

[CPAPhelpseeker]

Hello, I am a new CPAP user looking for advice on some weird results I saw after the first few nights.

Background: I am a mid-20s male, not overweight and generally healthy, but I have family history (family has OSA and CSA in different people), and I have moderate-severe bruxism/teeth grinding which I wear a nightguard for. I very rarely feel fully rested, but I wouldn't say I have severe fatigue (my day-to-day life isn't too affected). Many years ago, I used to use a low-dose benzodiazepine for sleep (as my father has for decades), and it worked wonders for feeling rested, but I decided that I didn't want to start on a dependency-causing drug at such a young age, so I stopped years ago and have just pushed through tiredness ever since.

A few weeks ago, I did a Lofta at-home sleep test, which came back with mild-to-moderate sleep apnea:

• AHI 8.3
  
• RDI 26.8
  
• Oxygen saturation 90-95% throughout the night
  
• Recommendation for Auto-CPAP with settings 4-20 (sounds like boilerplate recommendation)
  
• I can post screenshots of this data if useful
  

I started with a ResMed 10 Autoset with full mask F20 a few nights ago and have had some weird results. Normally, I am a pretty slow and light breather, both during the day and at night (my girlfriend tells me I look like I'm dead when I'm sleeping). With the CPAP on at night winding down for sleep, I feel like the machine is forcing me to breath faster than I normally would. After a few seconds breathing out, it will create a fast oscillation that disrupts my rhythm and makes me breathe faster. 

Next, and the bigger reason I'm writing this post: I was woken up to what felt like the mask bouncing on my face, and the machine pushing air in and out once per second, forcing my mouth/cheeks to flap open and closed. It almost felt like some sort of resonance between my lungs, mouth, mask, and the control algorithms in the machine forcing me to hyperventilate. When I opened OSCAR, I saw a period where the respiration rate had MAXED OUT at 50 cycles per minute, and sustained for a long period of time. I've attached screenshots of two days of data. I omitted last night's data, but can upload if needed (it shows a ton of mask leakage and several hours of this weird hyperventilation).

Additionally, during the day for the last few days my lungs have felt sort of weird, but I understand this may be a normal part of getting used to the CPAP. The crazy breathing oscillation/hyperventilation is more concerning to me, though.

Any suggestions on what the issue is?
Should I change my pressure settings? It seems like I have the default 4-20, EPR off, etc.
Different mask, or different looseness/tightness? I'm using the F20, but I also have an N30i I could try
Does it sound like I have some other sort of sleep issue that wouldn't be treated by an Auto-CPAP or detected by the Lofta at-home test? 

I welcome any advice, thank you!

[PeaceLoveAndPizza]

Your pressure is low and that may be a major contributing factor. Start with more usable settings.

Mode APAP
Min pressure 8
Max pressure 15
EPR 3 full-time
No ramp

use those settings for a few nights and post some charts. We can help fine-tune from there. If for some reason it goes off the rails, let us know.

[Jay51]

I agree with PeaceLoveAndPizza.  Look at your OSCAR chart in how your respiratory rate starts to go higher and higher when you your flow limitations increase significantly.  They line up on your chart.

[CPAPhelpseeker]

Thank you both for the suggestions! One question though: On the "optimizing therapy" page, there's a note about how OSA is often improved with higher pressure, whereas CSA is often improved with lower pressure. Are the "clear airway" events indicative of central apnea? It looks like those might correspond with the sections of fast breathing.

Also on the "sleep report" on my machine, it's reporting an AHI of 11.7, total AI of 10.7, and Central AI of 9.6. Does that mean central apnea is the primary factor here?

[Jay51]

Your CA's may be treatment emergent.  That is common among beginners in therapy.  Due to the increased oxygen intake and clearance of CO2, some CA's can develop.  Most people get over the CA's in a few weeks to a month or so.  Keep posting charts to see if your CA's are treatment emergent or if you have real CA's.   If you had predominantly CA's on your sleep study, then you may have real CSA.  We will see how you react to the higher pressure also:  if it increases your CA's and hyperventilation or if they stay the same or decrease.