Increase in Central Apneas Luna G3 PAP Link Data

[thowle]

New user on the Apnea Board, but I have had my Luna G3 unit since September of 2022 when I was diagnosed with severe obstructive sleep apnea from a home sleep study, having a peak of 70 AHI on one of the test nights, with a peak period of 15-minutes below 88%.  Therapy got these down to <1 AHI during the first month, but has seen a gradual increase -- still below 5 AHI, but a majority seem to be CSA events.

I remember feeling decent after starting therapy, but there were a few times that I would feel more sluggish during the day, so decided to adjust some of the settings (namely the min pressure) quite a few times, including enabling the Reslex EPR (off by default; ran with it on all ranges for a few weeks at the beginning, as it REALLY helped get used to the mask and pressure at the beginning, but ultimately turned it off and left it off).

A little side topic: I started feeling some heart palpitations a few months ago and also noticed that my resting heart rate as measured by my FitBit, both during sleep and during the day while in the office went from the mid to high 80s before therapy to the high 40s and 50s during sleep, and high 50s and 60s during the day, so I got a Wellue O2Ring and a Kardia 6L pocket ECG just for peace of mind -- not entirely sure yet on the cause of that, or if the therapy finally triggered a response and it's overall a good thing, no clue.  The ECG readings were all normal sinus, and overall O2 readings during the day and at night are all in the mid to high 90s.

Lately, I've had that feeling of being more sluggish, disconnected, and forgetful throughout the day, so I decided again to raise the minimum pressure.  I also saw a post on this forum by Chrisr that led me down the path to pull the SD card and get the PAP Link Software (had to use the link on this forum, since it's behind authentication on the BMC site now).

Honestly couldn't remember what all changes I made to the device, but luckily it looks like all of the core history was still on the SD card, with the exception of detailed flow metrics beyond the past few months.

I want to make sure I'm understanding the measurements and events right from the PAP Link software.

   

This is just a random day, but I found a CSA event, and then what I think is the corresponding flow restriction that triggered it.

• Are those annotations correct on showing the respiration cycle, where the increase in flow represents inhalation, followed by exhalation -- and the orange highlighted box represents what was actually the CSA event where there was a deep respiration cycle, followed by a few seconds of no respiratory activity?
  
• If so, I wonder why the event doesn't match the exact time of the flow restriction or lack of activity?  Just a data quality issue?
  

Not sure the best way to represent this on this post without a different type of chart, but here is summary view of the AHI/AI since therapy started -- you can see an increase over time, as well as some of the pressure adjustments that I made:

   

First Month (Original RX and Configuration)

• Mode: AutoCPAP
  
• Initial P: 5.5 cmH20
  
• Set Min APAP: 8
  
• Set Max APAP: 16
  
• Actual Average: 7.7
  
• Actual 95th Percentile: 8.3
  
• Actual Max: 8.9
  

I've increased the pressure and finally landed on a min of 15 and max of 20.  I tolerate it fine when sleeping, but not sure it's doing much since the latest charts are pretty much exclusively showing CSA (central sleep apnea) events instead of OSA (obstructive sleep apnea).

Is the increase in central apneas of any concern, or in any way related to me increasing the pressure when it maybe wasn't needed?  Perhaps should I just revert back to the original minimum pressure setting and let AutoCPAP do its job?  If they are actually CSA events, does that indicate something neurological that I should circle back with the doctor on?

Not sure how accurate the software is at classifying OSA vs CSA, but even going back to the beginning of therapy and randomly looking through a few days of graphs in PAP Link, it seems there are more CSA events than OSA.

   

[thowle]

Actually, that last part is incorrect. The charts from the first two months of using therapy don't show many CSA's at all. Once I bumped the pressure from 8 to 10, they started to appear more frequently. Maybe that does mean that this was brought on mostly by me increasing pressure when really the initial 8 was treating it just fine?

Any correlation to increased pressure and increases CAs? Further, any relation to heart rate or perhaps those palpitations?

[thowle]

Quick update from last night, I made a major change from the 15 cmH2O pressure down to 8 cmH2O, still in AutoCPAP mode with a maximum of 20; EPR (Reslex) was left OFF.

The 95th percentile pressure was 8.5, with a max of 9 for a little over 7 hours of sleep.

The AHI was 0.1 and measured only one OSA event at the end of use, which probably wasn't even an actual event (see below).

The overall flow inspiration peaks per (normal) breath seem lower (around 100 LPM, vs the 130+ LPM with the higher pressure).  Also not sure if the pattern of volume increasing then decreasing and repeating is something to worry about?

   

I did wear the O2Ring and got some weird results -- SpO2 ranged from 98 to 89, with the average being 95.  HR was from 45 to 190, but I'm wondering if the few high spikes were erroneous data (one of them directly correlates to a zero flow on the CPAP, which is when I got up in the middle of the night to go to the restroom, so perhaps the movement was causing it to have a false reading; and perhaps the others were when I was laying on my arm or something).

The drop in SpO2 does not align with any abnormal breathing patterns, increased pressure or registered events from the CPAP.

   

[Jay51]

It could be concerning if the heart rate reading is accurate and you jumped to 190 or so around 2 times.  Hopefully these are one-off artifacts.  If the heart rate trend continues (rocket spikes - tachycardia) up to around 190 or so, it would be wise to at least mention to PCP and possibly getting a Cardiologist involved (if you don't already have one).  All of this may be old news to you though.  

There is something called POTS - where transitioning from sitting laying to standing can cause a brief tachycardia.  You lined up one spike with getting out of bed, but not the other one; so not sure about this.  Can mention it to your Dr.'s also.

[thowle]

It could be concerning if the heart rate reading is accurate and you jumped to 190 or so around 2 times.  Hopefully these are one-off artifacts.  If the heart rate trend continues (rocket spikes - tachycardia) up to around 190 or so, it would be wise to at least mention to PCP and possibly getting a Cardiologist involved (if you don't already have one).  All of this may be old news to you though.  

There is something called POTS - where transitioning from sitting laying to standing can cause a brief tachycardia.  You lined up one spike with getting out of bed, but not the other one; so not sure about this.  Can mention it to your Dr.'s also.

Good points.  I also forgot to mention that I had my FitBit on my other arm, and it didn't detect any abnormalities for the period.

It did detect the spike when I got out of bed, but only up to 80.

Not sure which one is accurate; hopefully the FitBit.

Will try the O2Ring actually on my thumb or all the way on my index finger tonight, instead of just the first bend.

[thowle]

Night two update after the significant drop in pressure (15 to 8).

The pressure remained constant at 8 with exactly 8 hours of sleep.

The AHI was 0, measuring no events.  SpO2 ranged from 98 to 90, with the average being 95.  Drops >3%: 5 times (0.6/h), drops >4%: 2 times (0.3/h).

Similar to last night, there are a few noticeable flow restrictions, bimodal inspiration waveforms and shallow breathing.

   

Same anomaly as the other night on heart rate.  I did not get out of bed at all, though.  Again, not present on the FitBit summary data in the app, but I've not been able to download higher resolution data from FitBit to analyze yet.

   

Below is an animated GIF scrolling through the data in Excel with conditional color ranges;
   

I'm going to download the FitBit data and see if there is any correlation, and also contact Wellue and see if there is any change the sensor is faulty, as well as probably get another unit (same or different) to try at the same time.

Really don't feel like going to the doctor and going through whatever hoops you would need to with a cardiologist.

[Jay51]

Great job monitoring.  I hope you get it figured out also.  I have the Wellue Sleepu wrist watch/finger sensor monitor.  I have never had any problems with it.  Some members have reported problems with the Wellue O2 ring though.  Mainly when the sensor moves on the finger, lots of artifacts are produced.  

Getting a different spo2 monitoring device might settle the score.  Supposedly, having the sensor on the fingertip is better than higher up on the digit.  My sleepue has little prongs that push the sensor tighter against the skin (acts like a small turniquet) , so as to reduce errors.

[thowle]

I was able to get an export of the FitBit data and transform it a bit so that it fit into the 4-second buckets that the Wellue O2Ring produces.

For the most part, there is alignment and consistency, except for the anomalous spikes.

       


There are areas where the O2Ring logs motion, followed by an increase to the HR, which is also represented well on the FitBit data.

   

[Jay51]

Huge discrepancy in the 2nd chart when it shows 139 on O2 ring and around 60 or so on Fitbit.  One is obviously off.  A third device may settle the score.  

This is kind of strange with the o2 ring also.  When artifacts usually occur with Spo2 testing, the sensor dislodges and the spo2 reading drops lower dramatically.  So the average is distorted lower (and not higher).  On a cap/ox test that I have taken, when the sensor dislodged, it showed a long spike straight down (obviously an artifact).