Still confused

[Brian2]

Hi again
I am sorry to bother you all again with almost the same question as last time, but I am still concerned that the results I am seeing each morning are not as good as they should be. It is confusing to say the least.

I am particularly concerned about the leak rate which was averaging 3.8 for the last month, but last night was 5.4. It seems as though the trend is to be higher than when I first used the mask.

The mask is still giving a 5 star and excellent report every morning and has done consistently every morning for 6 weeks with only one exception.

My AI/HI/AHI is higher as well; the average for the last month: AHI 6 (last night 7.5), AI 0.4 (last night 1.3), HI 5.5 (last night 6.2). I know that I should not look at individual nights but the trend does seem to be getting worse results.

The sleep centre set my pressure at 4 and 20. There has been discussions here that suggest this variation is too high
Any advice/comments are welcome.


Thanks

[ozij]

Hi Brian,
First of all: how are you feeling?

Next: What is the machine's recommended pressure (the pressure at or below which you spend 90%, or, for Resmeds 95% of the time)?

Resmed machine's are known to score more events as hypopneas than other machines - you shouldn't be concerned about that.

Your AI is excellent.

If you want to make changes to your pressure, you can probably nudge the bottom pressure up gradually - depending of course on what the 95% is.

But don't get obssessive the numbers - the therapy's effect should be in how you feel as much as in the numbers.

O.

[Brian2]

Hi Ozij,
Q: First of all: how are you feeling?
A:Better than when i first started treatment about 2 months ago, but no "lamb in spring" as someone else so aptly called it.

Q:What is the machine's recommended pressure (the pressure at or below which you spend 90%, or, for Resmeds 95% of the time)?
A: It was first set at 14 (That is what i was told i needed)
I hope this is what you asked.

[ozij]

Good, I'm glad you're feeling better - and I hope it will get better and better.

The sleep centre set my pressure at 4 and 20

It was first set at 14 (That is what i was told i needed)

Now I'm a little confused, so let's to through this step by step.

Your machine can be setup to work in either an automatic (self adjusting) of fixed mode.

On automatic, the pressure can range from to bottom limit to the top. The default bottom is 4, the default top is 20.

In Auto Mode:
The majority of us have discovered that when the bottom pressure is too lay, we get more events that we want to have.

Many of us have also discovered than when the range is wide, we are wakened by the pressure changes, so we prefer a narrower range, or even fixed pressure.

In Fixed Mode:
The machine is set at one single pressure, and will supply only that pressure. You machine, in fixed mode also has Expriatroy Pressure Relief.

Do you know what mode your machine is on now, and on which pressure, or pressure range?

The data you reported here viewtopic.php?p=240238#240238

Pressure: Median 7.3 95th percentile 9.9 Maximum 10.9

AHI & AI Events/hour
Apnea index 0.8
Hypopnea index 6.6
AHI 7.4
% time in Apnea 0.2
Average daily usage 6.43

is also great. If you want to make chages based on that, then I would set up the machine on auto at 7.5 or 8 or 8.xx or 9 for the bottom to 11 top.

Where did you get the 14 from?

O.

[Brian2]

Hi O,
Sorry for the confusion. I was first issued a CPAP and this was set at 14. I then went and bought an APAP and the range was set at 4 to 20. The machine is on automatic.

I am probably guilty of reading too much on this subject too quickly. i have noted that lots of people have been suggesting that a range 3 below and three above is about right and so thought maybe my worsening resuklts were caused by this. I thought the last figures i quoted were not good enough and these were worse.
I also thought that if the leak rate was above 0.4 that a thunderbolt would come from heaven and strike me down dead. The same thing if my AHI gets above 5. If you think that the figures are OK then i thats all thats really great.

Sounds like i may be worrying too much through lack of understanding. Thanks for the feedback.
Brian

[packer]

my guess is you will do well - based on your pro-active attitude

you are doing pretty well already

people here tend to not want to tell you what to do- which is just
how this forum works- it is about sharing and learning

I have an aflex machine- I raised my bottom pressure to 8.5 because it felt
like not enough air at lower [ kind of felt like I need more- like I
was slightly starving to breathe] how that can be when we have a
wind machine blowing air into us is beyond me!!

anyhow- if you have a new, properly working apap you should be OK- what others are telling you is that some apneas can slip through before machine can react when your machine is set so low [the 4 bottom setting]

to me - again this is just me- the top number doesnt much matter
it doesnt seem to go beyond about 16 in my case- and spends 90%
around 12 or 13 [thats your 90% number- where it is most of the time
when it is fighting your windpipe closing]

do you have a bed partner? ask them about your mask leaking
they can probably tell you whats happening

your mask always leaks- different mask have different leak rates
think about it- the exhaust holes are leaks

if this is too simplistic I apologize- my thought are with the
newbies and they are who we all need to help I think

packer

[bdp522]

I agree that the machine may not be able to get from a setting of 4 up to what is needed to open the airway(titrated pressure of 14) in a reasonable time. I would set the lower number to no lower than 11 or 12. You can leave the top number at 20 if it doesn't cause problems(like snore chasing). Keep in mind some of us do better at one set pressure (cpap).

Brenda

[rested gal]

Hi Brian,

ozi was asking... when you look at the efficacy data in the machine's window, what is the "pressure" number it shows for "monthly?"

That pressure number is the "95th percentile" number. It means that 95% of the time the machine used that pressure AND pressures BELOW that pressure.

The 95th percentile number is often the single pressure a doctor would prescribe if a person were using an autopap just for a trial -- a trial for the purpose of finding an effective single pressure to put the person on after the autopap trial is finished and the person is given a straight cpap machine.

If 14 was what had been prescribed for straight cpap, I'd set the autopap at a range of 10 - 20.

Pressures "up there" which the machine never actually uses for you don't matter. If, say, 16 is the most the machine ever needs to use for you, it doesn't matter if the maximum is set at 20.

What really matters (imho) when using an autopap...is setting the minimum pressure up high enough that most events (apneas/hypopneas) are prevented right from the start.

I'd set that minimum pressure much higher than "4." Especially since you had been prescribed 14 with straight cpap. I'd leave the max at 20.

I agree with ozij:

Your AI is excellent.

If you want to make changes to your pressure, you can probably nudge the bottom pressure up gradually - depending of course on what the 95% is.

But don't get obssessive the numbers - the therapy's effect should be in how you feel as much as in the numbers.

The only thing I'd do differently is...I wouldn't go gradually with the moving the minimum pressure up. I'd go on and set the minimum at 10.

I like your sense of humor, Brian!

I also thought that if the leak rate was above 0.4 that a thunderbolt would come from heaven and strike me down dead.

Not quite. But I'd definitely be looking into why your leak rate is considerably higher than that.

[Treesap]

Brian,

I have the same machine, and originally my pulmonologist set my range the same (4-20). Since then, I have increased my minimum pressue up to 8. I find that the majority of the time my pressure is anywhere between 9 and 10.4. I also decreased the higher pressure down to 12. I know people here say that isn't necessary, but it helps me menatally.

[Brian2]

[quote="rested gal"]Hi Brian,

ozi was asking... when you look at the efficacy data in the machine's window, what is the "pressure" number it shows for "monthly?"

Oh Ok, (another little learning curve there <g>) that number is 10.6. I just got that from the clinical menu. It was 9.8 average for December( i noted this each day before I knew about the clinical menu) and was 9.3 average from 1st to 16th of january (i stopped logging daily after I found the clinical menu). Does the increase to 10.6 mean anything significant?

I know that, for the first few weeks i had almost no leaks becuase on my evaluation they commented on it. They now seem quite high. I am very consistant with cleaning, but I am definately noticing leaks, which i didn't notice a week or two ago. I am also sleeping more on my back.

Still, it really help to hear that my AI is good and the rest of the results "not bad".

So in short; there is room for improvement in everything, but the results could be far worse, and i should increase the minimum pressure. Thanks everyone. This list really helps tyhe newbies......thanks.
Brian
p.s. any comments at all on this are still more than welcome!

[rested gal]

Does the increase to 10.6 mean anything significant?

I don't think so. 9.3, 9.8, 10.6 -- there's not much difference there. I'd round 'em up and down and say, "Hey, I'm a 10 !!"

I know that, for the first few weeks i had almost no leaks becuase on my evaluation they commented on it. They now seem quite high. I am very consistant with cleaning, but I am definately noticing leaks, which i didn't notice a week or two ago. I am also sleeping more on my back.

(I added the bold highlight.)
Very good observation, Brian. Yes, the slight increase in 95th% pressure the machine is using now could certainly be because you've begun sleeping more on your back. Apneas and hypopneas are apt to hit hardest and heaviest for most people when they are sleeping on their back..."supine." Machine might be having to use slightly higher pressures more often nowadays for both reasons -- to handle the higher leak rate and to prevent events when you're on your back.

[xyz]

RG wrote:
> If 14 was what had been prescribed for straight cpap,
> I'd set the autopap at a range of 10 - 20.

I have a BiPAP Auto M with BiFlex. It is currently set with fixed upper and fixed lower numbers, like a traditional bipap. I see in your signature line that you have this model also. How does the "auto concept" work with bipap, where there are _two_ settings, an upper and a lower?

Is there a separate pair of high and low numbers (min/max) for each of the two bipap settings?

Do the high and the low settings roam independently? That could be a little tricky.

[Brian2]

[quote="xyz"]
I have a BiPAP Auto M with BiFlex. It is currently set with fixed upper and fixed lower numbers, like a traditional bipap. I see in your signature line that you have this model also.

Hi xyz,
I have a Resmed Autoset Spirit 2.
Brian

[rested gal]

How does the "auto concept" work with bipap, where there are _two_ settings, an upper and a lower?

Is there a separate pair of high and low numbers (min/max) for each of the two bipap settings?

If autotitrating bilevel mode is turned on, there's just one setting for IPAP and one for EPAP. They are called "min EPAP" and "max IPAP."

Do the high and the low settings roam independently? That could be a little tricky.

The machine will start out each time using just 2 cm's more for IPAP than whatever the EPAP is set at.

For example, if min EPAP is set at 10, and max IPAP is set at 20, the machine will start out each time using EPAP 10, IPAP 12. Both pressures will then roam independently of each other.

"Independently", to a point....

They can never get closer than 2 cms to each other. They can never range farther apart from each other than 8 cms.

EPAP should be set high enough to prevent all apneas. Just apneas.

IPAP handles the other stuff -- hypopneas, flow limitations, and residual snoring.

If EPAP is set "right" (high enough to prevent obstructive apneas) EPAP usually doesn't have to move up much, if any, all night. IPAP will be the "busy" one.

When you have autotitrating turned on, there's a setting called Max Press Sup. That governs how far apart EPAP and IPAP are allowed to work independently of each other. Here's a link to the way I understand that:

viewtopic.php?t=22099
Jul 14, 2007 subject: What is 'Max Press Sup'

viewtopic.php?t=15666
Dec 08, 2006 subject: Question for BiPap users - UPDATED 12/14/2006

[bigk]

Brian - at 4cm you are probably struggling to even breatthe.

4-20 is the DEFAULT setting for the machine.

I agree with rested girl - set your minimum to 9 or 10. I found when I increased the minimum pressure that my maximum pressure dropped. If you look at the efficiency data, you can see what the pressure was from the night before -it reports the pressure at which you spent 95% of the previous night.

IF that pressure is say 14, I'd bring down the upper limit to 15 most probably.

The ASII seems to work better with a smaller spread.

Hope this helps