Leaks Under Control: Now What?

[Tallen234]

I know a few of you have been following my immersion into CPAP therapy. Here are the previous threads:

viewtopic.php?f=1&t=35816&p=309607#p309607

viewtopic.php?f=1&t=35347&p=303480#p303480

I think I finally have my leaks under control, but I am still getting similar results - ok AI indexes, but high HI indexes.

Here are the results from the past two nights:






I can't seem to eliminate the HI's. I am still waking up a few times throughout the night, but have been doing much better. However, I still wake up unrefreshed.

Any help?

[Gerald]

I tried to read your charts...but failed.....too small to see.

What pressures are you running?

[jnk]

First, you pat yourself on the back and celebrate, because controlling leaks ain't easy, and you did it.

Then you pat yourself on the back for low AI, which is the prime thing on a ResMed.

Then you settle back for a few more weeks/months to let your body and mind get used to everything now that your leaks are under control, remembering that ResMeds score any slight flow limitation as a hypopnea, thus making your AHI number look scarier than it really is.

Eventually, you may need to raise pressure to get your AHI lower, if you aren't feeling great. But it takes time for some of us to start feeling better, and you just now got your leaks under control, so are just now getting good therapy.

[Tallen234]

Right now I am running 9.4 to 18. I will see if I can edit the file, but it took me a while to get it to the stage it is.

I tried to read your charts...but failed.....too small to see.

What pressures are you running?

[ozij]

I can't seem to eliminate the HI's. I am still waking up a few times throughout the night, but have been doing much better. However, I still wake up unrefreshed.

What is your 95% pressure now, that the leaks are controlled?

"Eliminating" hypopneas on a Resmed is more difficult because of how the machine reports breathing events. However, some of those hypopneas reported may be of the kind one can elimitnate with higher minimum pressure. So try to raise the minimum - gradually.

O.

[TerryB]

I'm sorry that I can't make a reply based on your charts. I can't read them and I'm not familiar with the Resmed layout so I could anticipate what the lines and chart axis values are saying. However, if your AI is way down there, consider whether you are allowing enough sleep interval. I don't use an alarm clock, haven't for years, but I wake up ready to go about the same time every morning eight hours after I go to bed. Please check if you are allowing yourself enough time for sleep.

regards,
TerryB

[DreamStalker]

Yes. What ozij said. Use your 95% and set it as your min pressure.

[lktnky]

What's the difference between 'Calculated Pressure' and 'Pressure'?
My ResScan reports list 'Median, 95% Pressure & Maximum' under 'Pressure' and '95% Epap' and '95% Ipap' under 'Calculated Pressure'.
I wish I understood all this.

[Tallen234]

This raises an interesting issue, it appears than when I increase my pressure, the 95% pressure seems to go up.

For example:

11/16 Min Pressure 9.4 - 95% Pressure - 9.6
11/17 Min Pressure 9.4 - 95% Pressure 9.8
11/18 Min Pressure 9.4 -95% Pressure 10.0
then I changed Min Pressure
11/19 Min Pressure 10 - 95% Pressure 10.6

I am thinking about keeping it at 10 for a while to see what happens.

I can't seem to eliminate the HI's. I am still waking up a few times throughout the night, but have been doing much better. However, I still wake up unrefreshed.

What is your 95% pressure now, that the leaks are controlled?

"Eliminating" hypopneas on a Resmed is more difficult because of how the machine reports breathing events. However, some of those hypopneas reported may be of the kind one can elimitnate with higher minimum pressure. So try to raise the minimum - gradually.

O.

[jnk]

What's the difference between 'Calculated Pressure' and 'Pressure'?
My ResScan reports list 'Median, 95% Pressure & Maximum' under 'Pressure' and '95% Epap' and '95% Ipap' under 'Calculated Pressure'.
I wish I understood all this.

Only Velbor and dsm understand such things. I know I don't. I get the feeling that the copy editors ResMed uses defer too much to the engineers. But I think your question may involve the fact that you are using an auto bilevel, the VPAP Auto. That may be part of why the wording is at it is in ResScan for you. Not a problem for the original poster using an AutoSet II, which is not a bilevel.

But I would ignore the word "calculated." The numbers the machine records are averages calculated every minute, and then the software makes calculations on top of those calculations.

The most confusing thing (to me) with the VPAP Auto in VAuto mode is that its innards record, once a minute, the average of what ResMed calls the "AutoSet" pressure. The AutoSet pressure is not the IPAP pressure or the EPAP pressure. It is the point exactly in the middle of those two pressures. That way the innards only have to record one number as the average instead of two linked averages. So when the machine gives you your "pressure" in VAuto mode, it is giving you the AutoSet pressure. The ResScan software takes the numbers the machine gives it and uses the pressure support number (the distance between IPAP and EPAP) to figure out the IPAP and EPAP numbers.

That is my conclustion based partly on ResMed's explanations below:

The pressure transducer located in the VPAP Auto measures treatment
pressure; the average pressure is calculated and recorded each minute (VAuto
mode: average AutoSet pressure . . . ). The pressure
reported in the Efficacy Data submenu . . . for a single session is the 95th centile pressure for mask-on
time (VAuto mode: 95th centile AutoSet pressure . . . ) excluding periods when the leak has exceeded 0.4 L/s
(24 L/min).

AutoSet pressure is a conceptual value. The patient is delivered an auto-titrated
inspiratory and expiratory pressure based on the AutoSet algorithm, which has
the AutoSet pressure as its midpoint. The AutoSet pressure is reported in data
management and efficacy results information.

[lktnky]

My pressures are set at 8/18 and I've been getting very low AI and good HI (after halving it).
I still don't understand but thanks very much for trying!

[ozij]

I get the feeling that the copy editors ResMed uses defer too much to the engineers.

And I always remember what I learned about who gets to write the manual from "Zen and the Art of Motorcycle Maintenance"....

O.

[jnk]

I get the feeling that the copy editors ResMed uses defer too much to the engineers.

And I always remember what I learned about who gets to write the manual from "Zen and the Art of Motorcycle Maintenance"....

O.

Since Pirsig said in the book that "writing and editing technical manuals is what I do for a living," he was undoubtedly in the best position possible to know that such manuals were all "full of errors, ambiguities, omissions and information so completely screwed up you had to read them six times to make any sense out of them."

Nothing better in a writer than being comfortable with irony.