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[Diagnosis] AHI <2 over 5 months. Any need for a deeper dive? - Printable Version

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AHI <2 over 5 months. Any need for a deeper dive? - jpthuot03 - 06-10-2022

Thanks for accepting me to this board!

I've had my AirSense 11 since January, and only today did I pull the SD card to have OSCAR take a look at it.  My question is if my AHI is good (avg. 1.35 over 5 months) is there any reason to dig further into this data?

I haven't gained any super powers since starting with CPAP, but I certainly feel more rested and mentally alert throughout the day.  Last year I was napping at least twice a day, and that has stopped as well.

Thanks in advance for any feedback.


RE: AHI <2 over 5 months. Any need for a deeper dive? - OpalRose - 06-10-2022

Sounds like you're on the right track with your therapy.  You state that you feel more rested and mentally alert, and that's important.

There's probably no need to "dig further", but no harm if you want us to take a look.

Follow the link in my signature line to Organize your chart and then use the Attachment Feature to post here.

And Welcome to Apnea Board!


RE: AHI <2 over 5 months. Any need for a deeper dive? - jpthuot03 - 06-10-2022

Ok, well after reading your OSCAR post, here are two screenshots from last night's session.  

Thanks![attachment=42662][attachment=42663]


RE: AHI <2 over 5 months. Any need for a deeper dive? - staceyburke - 06-10-2022

Your pressure is making out and you should not have to go that high. ResMed raises pressure when there are flow limits.

Flow limits are apnea also and the way they are treated is with EPR. your EPR is turned off. I would make the following changes and see how you feel after a couple days.

EPR on FULL TIME
EPR 3


RE: AHI <2 over 5 months. Any need for a deeper dive? - jpthuot03 - 06-10-2022

(06-10-2022, 02:21 PM)staceyburke Wrote: Your pressure is making out and you should not have to go that high.  ResMed raises pressure when there are flow limits.  

Flow limits are apnea also and the way they are treated is with EPR. your EPR is turned off. I would make the following changes and see how you feel after a couple days.

EPR on FULL TIME
EPR 3

Thanks  Thank you, I'll try that tonight.


RE: AHI <2 over 5 months. Any need for a deeper dive? - multicast - 06-11-2022

"Flow limitation" is ResMed's Golden Calf. Keep in mind that a *physical* flow limitation -- something happening in your body -- is a non-linearity between the esophageal pressure and the breathing effort.  In laymen's terms: your chest is moving up and down, hence an esophageal pressure can be detected, but you are not breathing.  This pressure can only be measured in a lab -- either by swallowing a probe or by some belts around your breast and belly.  

Now what ResMed calls FL is an (admittedly clever) *grade of breathing quality* by analysing the flow rate, "0" correspond to an "A" and "1" to an "F",; let's call this "RFL".  (This interpretation may be wrong, als all interpretation may.  For example, a heavy FL may be considered as double breathing, reported as an insane high minute ventilation. Or misreported hypopneas.)  This interpretation may or may not correspond to the real thing, i.e., a physical FL.  

The machine's goal by all means is to achieve a high grade of breathing quality (RFL) by increasing the pressure -- what else can it do?  In many cases that strategy is successful, but is may cause other problems, pressure induced CA, e.g.  

EPR generally gives a better grade, that is a lower RFL, hence the pressure won't rise as it would do without EPR.  But it also triggers CA ...  

In your data I see no need for EPR.  First of all, the lower pressure is way too low.  The machine wants you most of the time at around 9.  As the lower limit is 7.4 is unnecessarily low it tries to return to that value and shoots up to prevent events, at 5:45 for example.  I would set the pressure from 8.8 to 13, no EPR.  And engage mode "soft": the machine responds less "aggressive" then.  

Most important: you feel better with the therapy.

Mike


RE: AHI <2 over 5 months. Any need for a deeper dive? - jpthuot03 - 06-11-2022

(06-11-2022, 06:09 AM)multicast Wrote: "Flow limitation" is ResMed's Golden Calf. Keep in mind that a *physical* flow limitation -- something happening in your body -- is a non-linearity between the esophageal pressure and the breathing effort.  In laymen's terms: your chest is moving up and down, hence an esophageal pressure can be detected, but you are not breathing.  This pressure can only be measured in a lab -- either by swallowing a probe or by some belts around your breast and belly.  

Now what ResMed calls FL is an (admittedly clever) *grade of breathing quality* by analysing the flow rate, "0" correspond to an "A" and "1" to an "F",; let's call this "RFL".  (This interpretation may be wrong, als all interpretation may.  For example, a heavy FL may be considered as double breathing, reported as an insane high minute ventilation. Or misreported hypopneas.)  This interpretation may or may not correspond to the real thing, i.e., a physical FL.  

The machine's goal by all means is to achieve a high grade of breathing quality (RFL) by increasing the pressure -- what else can it do?  In many cases that strategy is successful, but is may cause other problems, pressure induced CA, e.g.  

EPR generally gives a better grade, that is a lower RFL, hence the pressure won't rise as it would do without EPR.  But it also triggers CA ...  

In your data I see no need for EPR.  First of all, the lower pressure is way too low.  The machine wants you most of the time at around 9.  As the lower limit is 7.4 is unnecessarily low it tries to return to that value and shoots up to prevent events, at 5:45 for example.  I would set the pressure from 8.8 to 13, no EPR.  And engage mode "soft": the machine responds less "aggressive" then.  

Most important: you feel better with the therapy.

Mike

Thanks for taking the time to go through this with me, Mike. I appreciate it


RE: AHI <2 over 5 months. Any need for a deeper dive? - staceyburke - 06-11-2022

Clear airway or centrals are 2 types. The first is for some reason the body just does not take a breath. That type shows up in the sleep study and a SPECIAL type (ASV) of Cpap has to be used to stop them. You had no CA in the charts you put up so I’m pretty sure that your would be the 2nd type. 

The 2nd type is when the body is use to a high CO2 concentration in the blood. When they use Cpap they breath better and the CO2 level is lowered and that caused this type of CAs. Again, when you used Cpap your charts did not have any CAs but your flow limits were high and causing your high pressures. 

My suggestion is to try EPR 3 (which does get rid of more CO2 and can cause some CAs) and see how you do at that setting. Yes you could have some CAs but because you have no CA I would believe you would do well at 3. If not we would move it to 2 or 1. 

And so you understand even if you do have some CAs they go away as your body gets use to lower CO2 in your blood.

Flow limits are apnea and stop you from getting into deep sleep, can wake you up and drives up pressures where there are more large leaks.


RE: AHI <2 over 5 months. Any need for a deeper dive? - Gideon - 06-11-2022

To be clear. You are not having central apneas.

On EPR, Pressure Support, Flex causing centrals, yes it may, not does. BT W just the use of any CPAP may (not does) also cause central apnea. Is the solution not to use CPAP? Nope

You need to be aware of these facts so that if they occur you can respond appropriately. Many of us here are very aware of these facts, but we don't suggest holding back what has been proven to be safe and effective treatment on the chance that central apnea may, not will, show up. If it does we would suggest appropriate action(s) to mitigate it.

Oddly enough it is the need to vent CO2 that is the main driver for our breathing, not the need for oxygen.

CPAP as a technology helps all of us CPAP users to breathe better. This means we are better at flushing the CO2 out of our system. If we flush too much out we must address that and if needed we will.


RE: AHI <2 over 5 months. Any need for a deeper dive? - hh9797 - 06-12-2022

The way I see it is if you are feeling better and it is working there is no NEED to dig any further it is doing what it is supposed to do and it is working for you. BUT with that said if you are like me and interested in looking at data just to look at data then there is no harm in digging deeper. I personally like to look at the data, compare how the data looks on nights that I had my 1 daily soda late compared to say at lunch compared to say forgetting it and seeing if there is any significant differences between say days I work a 14 hour shift and am burnt out by bed time compared to days I was off of work and got to relax, etc, not for any treatment change purposes but purely because I am interested in cause and effect and if their is any significant data difference when variables are different just because that is the type of person I am. To me it is interesting that on days I have late night caffeine my obstructive is higher than my central, on days I have my caffiene mid to late afternoon my obstructive and central are roughly 50:50 +/-10 on either side and on days I skip my caffeine all together my central is way higher then my obstructive. I know correlation does not causation make but it is still an interesting observation.

So if it is working for you and you feel good there is zero reason to dive deeper to try to improve the score any because if it is working for you and you are withing the "normal" range there is zero reason to mess with what works, but if you want to dive deeper just out of curiosity then there is no harm in that either.