First night on AutoSet Spirit

Spiritus · Post by **Spiritus** » Fri Dec 17, 2004 11:42 am

Hi,

So last night I used my new Spirit for the first time and had a very restful sleep. Interestingly, although my titration study suggested that my pressure be set at 7, the Spirit reported that my pressure last night was 8.2.

Rob

Titrator · Post by **Titrator** » Fri Dec 17, 2004 12:13 pm

Hi Rob,

Sounds like you have found successful treatment, which is fantastic.

If you download a weeks or months worth of data, you may see that you are closer to your titrated pressure than you were last night.

It is important to have a PSG to determine a baseline pressure. You take that pressure and compare it to other autopap machines.

Congrats,

Ted

Spiritus · Post by **Spiritus** » Sat Dec 18, 2004 2:15 pm

Titrator wrote:Hi Rob,

Sounds like you have found successful treatment, which is fantastic.

If you download a weeks or months worth of data, you may see that you are closer to your titrated pressure than you were last night.

It is important to have a PSG to determine a baseline pressure. You take that pressure and compare it to other autopap machines.

Congrats,

Ted

Hi Ted,

Last night the pressure was 10, and my AHI was 9.3. On my first study, my AHI was 18.3. Does the AHI the Spirit reports mean that there were 9.3 events that it successfully treated or were the 9.3 events ones that slipped through?

Rob

Titrator · Post by **Titrator** » Sat Dec 18, 2004 2:32 pm

Hi Rob,

The AHI that the machine reports is the actual events that you had last night (per hour). You had 9.3 events per hour, down from 18 before.

The numbers will vary from night to night. The important thing is if you are feeling better and the overal trend is no more than 5 AHI.

I think you are off to a good start. If you can't get the numbers down to 5 AHI, I would either buy the Reslink and check your pulse ox, or rent a recordable meter and check it that way. As long as your pulse ox is 90 or above, you are ok.

Regards,

Ted

wading thru the muck! · Post by **wading thru the muck!** » Sat Dec 18, 2004 10:12 pm

Ted,

spiritus wrote:Last night the pressure was 10, and my AHI was 9.3. On my first study, my AHI was 18.3. Does the AHI the Spirit reports mean that there were 9.3 events that it successfully treated or were the 9.3 events ones that slipped through?

This is the $64,000 question... I've wondered this also but I did not pick-up from your comments what the answer is.

Example: The machine reports 5 apneas... are these ones the machine detected but did not resolve or are these the ones it detected and resolved.

You say "actual events"...what do you mean by that?

Spiritus · Post by **Spiritus** » Sat Dec 18, 2004 11:06 pm

wading thru the muck! wrote:
Example: The machine reports 5 apneas... are these ones the machine detected but did not resolve or are these the ones it detected and resolved.

You say "actual events"...what do you mean by that?

Yes, I find this a tad confusing. I was under the impression that the auto titrating units were able to eliminate apnea and hypopnea. If my sleep study showed no events happening at a pressure of 7, why then would an auto unit allow 9 events to slip through? Is the unit not able to eliminate hypopnea? I thought that was the idea...

Rob

rested gal · Post by **rested gal** » Sun Dec 19, 2004 12:11 am

I think these machines are designed to prevent most apneas and hypopneas. Most, not necessarily all. If you had lots of partial closings of your throat (hypopneas) I don't think you'd want a machine that yo-yo'ed up and down extremely aggressively, responding to the slightest limit of flow instantly. Constant up/down sudden spikes of pressure could be just as disruptive to sleep as the problem we got these machines to treat in the first place.

So (I'm just guessing here) while the designers made autopaps sensitive to changes in airflow (in order to prevent events) they also had to make the machine's response be gradual - for comfort's sake and to not disrupt sleep with sudden jumps in pressure. Pressure changes might look rather spiky when we look at these graphs, but when you think about how many seconds, how many minutes there are in those neatly marked hourly chunks of time, the actual movement of the pressure responses are very gradual. Inevitably, with a gradual response, a few events will sneak on through....actually occur and be registered on the graph. That's why an AHI under 5 is generally considered "good".... some events, but not too many. Even people with perfectly normal sleep and no OSA have occasional random events, so I think expecting (or trying to tweak) a machine to prevent every single event - giving us a clean chart and 0.0 AHI - would be unrealistic. And probably not even necessary for fully refreshing sleep.

When I first got the software for my autopap, I used to get the urge to tweak the machine every day, depending on whether the AHI had gone up or down a fraction of a decimal point the night before. It puzzled me that each small pressure tweak I made was not reflected the next day by what I expected to see in the AHI. The AHI figure seemed to have a mind of its own. LOL. As the newness of the toy (examining the software data with a fine toothed comb) wore off, and I began leaving a pressure range alone for a week or two or three at a time, I saw what Titrator mentioned....that the AHI simply is going to vary from night to night, no matter what.

Bottom line is how we feel. And we're usually going to feel the same (hopefully good) in the morning after seeing an AHI of 3.4, 2.6 or 0.9 - anything 4.something or below. The highest my AHI has been for months now was 3.something on one night. Usually mine ranges from below one to two.something. The real value of monitoring ourselves with the software, imho, is to note what happened if we start feeling very different, or are not feeling better/good. The data can be invaluable in helping us decide what might need to be changed - not only with the xpap therapy itself but other factors. For example, if we see we're consistently having a very low AHI, yet still feeling fatigued, there might be other things at play - disrupted sleep from factors other than just "events" which may be being treated as well as possible - perhaps hormones, vitamin/mineral deficiencies, other illnesses. The software is useful to at least help remove the question of, "Is my pressure right?"

wading thru the muck! · Post by **wading thru the muck!** » Sun Dec 19, 2004 9:03 am

rested gal wrote:I think these machines are designed to prevent most apneas and hypopneas.

R G, I think that too, but I want to know. I don't think I need to go to school and becoume an RRT to know a little about how to interpret the software with my machine.

I know the key is how you feel in the morning, but sometimes you wake up feeling lousy and it's resuring to look at the software to see that it's not the apnea causing it. Maybe as we get older and accumulate this pain and that ache it becomes more of a concern to know which ones causing the problem today. There's also that thing about men and gagets. We like to know exactly how they work!

Very good advice about not trying to over-tweak our machines. We perfectionists need a reality check once in a while

rested gal · Post by **rested gal** » Sun Dec 19, 2004 12:47 pm

There's also that thing about men and gagets. We like to know exactly how they work!

LOL, I understand what you're saying!

There's also that thing about companies and their closely guarded industry secrets. Dunno if you'll ever find out what makes these machines tick. Each manufacturer apparently uses its own pet algorithms. Keep digging, though! I like your spirit! (Or your remstar or your 420E, as the case may be.)

WillSucceed · Post by **WillSucceed** » Sun Dec 19, 2004 7:23 pm

"The important thing is if you are feeling better and the overall trend is no more than 5 AHI."

How did "5" get settled-on as the magic number? I had a few nights with a Spirit and my AHI was between 7.1 to 8.8.
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rested gal · Post by **rested gal** » Sun Dec 19, 2004 11:49 pm

Good question, WillSucceed. Perhaps an AHI greater than 5 starts perking up ears at sleep clinics? Maybe insurance companies or Medicare require an AHI greater than 5 (along with meeting other criteria) to even consider paying for treating OSA and that's how the "magic number" was arrived at? Dunno.

Something to consider is that the tick marks that an autopap's software adds up to come up with the "AHI" for any given night might not be an absolute reflection of what was happening for some individuals. I can't even begin to explain it (where's SWS when we need him!? lol ) but it seems that there will be some people whose breathing pattern might confuse one maker's autopap, but not another - or might fool all of them. In those cases, the events marked (or not marked) on a graph might not be an absolute indication of events.

There can also be a higher or lower AHI reported, depending on what mask was being used, since each mask type has its own unique airflow design - and airflow is what these machines go by when deciding "what's happening". Just as some people's breathing pattern can confuse some machines, so can some masks' airflow characteristics cause confusion for some machines when coupled with some people's breathing patterns. That's why I think the bottom line is really how a person feels the next morning after a night on his/her machine, regardless of the AHI number. A particular combo of person/machine/mask might consistently register higher than 5 AHI each night, yet still result in very restful sleep.

Two rather interesting discussions - one about lowering AHI and the other about the effect of a mask on data reports are here:

Discussion about lowering AHI - (continues for 4 pages)

Discussion about type of mask affecting data numbers

First night on AutoSet Spirit

First night on AutoSet Spirit

Inquiring minds want to know

Max AHI

Mask

Mask

Mask