Conrad wrote: ↑Tue Nov 23, 2021 7:24 am
I just now looked at my numbers from the My Air app. Not good. It showed a high leak rate of 23L/min and an even count of 7.4 events/hour.
Please understand what the numbers you see on the MyAir app actually reflect before going into panic mode.
The leak number is what we call a 95% leak number and all that means was the leak was AT OR BELOW 23 L/min for 95% of the night. That "or below" part of the definition is critical. This number seen does NOT mean an overall average leak number nor does it mean where a person was at in terms of leak for 95% of the night.
I would wager that when you can finally see the actual leak graph itself that for the bulk of the night the leak line was well below 23 L/min.
I have a good visual explanation here in this thread where the "numbers" look horrible but in reality the leak itself was only really bad for a short period of time.
https://www.cpaptalk.com/viewtopic.php? ... t#p1036669
Numbers don't tell the whole story.
So 23 L/min isn't all that horrible and most likely the bulk of the night the leak was below that and certainly well within the limits of the machine's ability to compensate for.
Now if the leaks are causing wake ups that is a different story but in terms of therapy effectiveness alone...it's not an issue.
Something to think about though is whether those leaks...even if small...could be causing arousals and with the arousals come the chance of false positive flagged central apneas. You may or may not remember arousals....it doesn't have to be a full awakening happening to get false positives.
You are having a worrisome number of centrals...so we wonder why.
First thing to check is are those flagged centrals real asleep centrals or are they post arousal centrals. If we aren't asleep when something gets flagged then it doesn't count in terms of apnea but can matter in terms of overall sleep quality itself.
Meaning the false positive flagged events could be a symptom of poor sleep quality and not necessarily the cause of poor sleep (arousals).
Second thing is what might have changed to cause the increase in centrals (assuming real asleep centrals)....medication side effects and altitude are prime thoughts in that area. Any medication changes or dosages????
Has your altitude changed? Higher altitude can certainly cause centrals. If temporary change in altitude then that will usually resolve once a person goes back to primary lower altitude.
To check for asleep vs arousal flagged events...watch the videos here to learn to spot the difference.
http://freecpapadvice.com/sleepyhead-free-software
If you see lots of arousals you can also look to see if the leak maybe increased prior to the arousal which might indicate that the leaks caused the arousal and the arousal may have caused the false positive flagged event.
Obviously you have to be able to utilize the SD card and computer software to evaluate any of this so I don't know how much evaluation you can do now.
But relying on just the MyAir data (which is the same data as the machine's LCD screen will show) the change in PS didn't really reduce the number of centrals....I assume though you didn't really give us a breakdown of the AHI when you reported last night's AHI of 7.4.....it's really important to know the breakdown into each category..
Was the 7.4 shown composed of primarily centrals????
It was something to try that might or might not have helped but would depend on if those centrals are for sure asleep centrals to even stand a chance of helping reduce the numbers. Zero chance of reducing the number of centrals if those centrals are arousal related flagged centrals. This is why it is so important to know what those centrals reflect....either a real asleep central or a false positive arousal related central. Gotta know exactly what we are fighting first.
Now...assuming for sure real asleep centrals the only thing you can really do is try altering PS to see if it helps or not.
Sometimes PS actually can cause centrals. It's a small number of people for sure but it can happen so that's why we try either reducing PS or even totally eliminating PS to see if it changes the centrals or not. It's a quick easy, cheap experiment to try. I have a friend who gets about 15 centrals per hour consistently with PS of 4 but essentially none with PS of 3. Go figure that one as being weird but it can happen.
Are your centrals a product of the PS??? We don't know for sure if they are or aren't but it's something to try that is within our control and about the only machine tweak we can try given this type of machine being used.
Given that you only have the data from the machine to evaluate at the present time and can't look at the flow rate right now....sort of flying blind but if the centrals didn't reduce with a reduction of PS....the next step is try simply turning PS off or setting to 0 (or maybe 1) and see if that makes a change.
If it doesn't then you are just going to have to wait until you are able to use OSCAR to get a better idea what is going on.