No Rhyme or Reason to Numbers

[DoriC]

DSM, Can you give an explanation for this ? I've never quite understood the secret of Auto vs Cpap except that my husband does much better on straight cpap also.

[rested gal]

Can you give an explanation for this ? I've never quite understood the secret of Auto vs Cpap except that my husband does much better on straight cpap also.

Wulfman (Den) has often said he found that autopaps' varying pressures seem to disturb his sleep.

I personally do equally well, and feel equally well rested, when using an autotitrating range or with straight cpap. Either suits me fine.

But, some people do seem to sleep more restfully using one steady pressure instead of the varying pressures an autopap might use throughout the night, even if the autotitration range is set fairly narrow.

For example, say it takes a pressure of 10 to keep a person's airway well and truly open all night. And say that that person is ultra sensitive to slight changes in pressure while sleeping. Even with a narrow autopap range of 8 - 10, the slight up and down changes between that minumum pressure of 8 and maximum pressure of 10 on autopap might disrupt some peoples' sleep, continually knocking them out of whatever stage of sleep they happened to be in when pressure changes happened. But, the same person might sleep fine if the autopap was switched to CPAP mode at a steady pressure of 10.

I suppose one could say that some people are just more susceptible to the "feel" of changes in pressure, even while sleeping. Those changes -- even slight, subtle changes -- could bother some people. Could cause arousals that they aren't even aware of, or even cause complete wakeups that they wouldn't have experienced had they been on a single straight pressure.

Here are some of Den's old posts about why he uses CPAP mode instead of AUTO mode with his autopaps:

Topic: auto cpap vs regular cpap machines
viewtopic/t35511/viewtopic.php?p=305142#p305142
from Den's post on Oct. 17 2008:
viewtopic/t35511/viewtopic.php?p=305142#p305142
"Leaks and snores can drive an APAP crazy with pressure changes."


Topic: Giving CPAP another try but need help
viewtopic/p391220/viewtopic.php?p=391017#p391017
from Den's post on Aug. 3, 2009:
"I found that the pressure changes disturbed my sleep, so I use straight pressure."


Topic: CPAP to APAP?
viewtopic.php?p=378722#p378722
from Den's post on June 21, 2009:
"I have nothing against Autos/APAPs.....I have several, myself......but I hardly ever use any of them in a range of pressures. In the first place, the changing pressures disturb my sleep. In the second place, the Autos can't respond fast enough to head off events, so many of the events occur anyway. They're not as "automatic" as some people think. (My AHI is usually higher when I use one in a range of pressures.) For them to be truly "effective", the minimum pressure has to be set high enough to prevent the vast majority of events......so, once you have THAT pressure, you usually don't need much above that pressure and a single pressure will usually suffice.
If a person is prone to mask leakage (as many of us are), APAPs can make for disastrous sleeping with the pressure changes. And, when it increases pressure, the leaks can become worse and it then becomes a "feeding frenzy" between leaks and pressure changes."


Topic: apap or cpap, which mode is better?
viewtopic.php?p=352829#p352829
from Den's post on Mar. 24, 2009:
"it's my understanding that when we're in certain stages of sleep, we're more susceptible to more apnea events. If our pressure is changing to stop those events at those times, it COULD disrupt our sleep.

Personally, I sleep much better in single-pressure (CPAP) mode."


Topic: Encore data from first night with mouth taped
viewtopic.php?p=242616#p242616
from Den's post on Feb. 1, 2008:
"Pressure changes for SOME of us, disturb our sleep. When a person/machine gets into a leak/AHI events/snore/pressure change situation, it can feed on itself and the pressure goes every which way.....as it was doing in your previous charts."


Topic: Why return to CPAP from auto-CPAP?
viewtopic/p334987/viewtopic.php?p=334875#p334875
from Den's post Feb 3, 2009:
"Nothing wrong with having an Auto.....I have several.....but use them all in single-pressure (CPAP) mode. I found that the changing pressures disturb my sleep and I get lower AHI numbers with straight pressure."

[cajun]

Well I took Cajun's advice and moved it from APAP to straight CPAP AND I lowered the pressure from 14 to 11. Voila! My AHI went down to 3.0. I also didn't wake up dizzy like normal. I'm losing weight, so hopefully I'll be able to lower the pressure even more in the future.

Yay me!!!

I've been here a few months and feel good to have helped a fellow hoser...even though all I actually did was relay the great suggestion that Den (big thanks again) gave me.

[spookydoo]

Interesting. My Neurologist/Sleep Doctor said that they prefer straight CPAP at Vanderbilt Medical Center. I find it interesting that not only have I gotten my best numbers to date by using straight CPAP instead of APAP (as I was doing), but I also lowered my pressure and got much better results.

[cajun]

Interesting. My Neurologist/Sleep Doctor said that they prefer straight CPAP at Vanderbilt Medical Center. I find it interesting that not only have I gotten my best numbers to date by using straight CPAP instead of APAP (as I was doing), but I also lowered my pressure and got much better results.

What you say is also interesting. When I asked my sleep doc if I should try CPAP since my sleep tech said, "You sure are sensitive to slight pressure changes! You woke each time I bumped it up." he told me "You have an APAP capable machine. Most people do better on it, so you should as well." Thank God for this site.

[DoriC]

Can you give an explanation for this ? I've never quite understood the secret of Auto vs Cpap except that my husband does much better on straight cpap also.

For example, say it takes a pressure of 10 to keep a person's airway well and truly open all night. And say that that person is ultra sensitive to slight changes in pressure while sleeping. Even with a narrow autopap range of 8 - 10, the slight up and down changes between that minumum pressure of 8 and maximum pressure of 10 on autopap might disrupt some peoples' sleep, continually knocking them out of whatever stage of sleep they happened to be in when pressure changes happened. But, the same person might sleep fine if the autopap was switched to CPAP mode at a steady pressure of 10.

RG, I think I've got it(maybe ) So on auto at 11-13, if one is sensitive to pressure changes or is in whatever stage of sleep and sleeping comfortably at 11 but suddenly needs the 12 or 13 because of an event, that change might disrupt sleep, cause restlessness,therefore maybe a leak,etc. I think that is what happens to Mike on auto. Last night I changed back to cpap at 12.5cms and his AHI was 0.3 with a nice straight leak line. On auto he also has a low AHI but he has leaks and doesn't feel as rested. Another issue is that he does fine at 12 or 12.5 but the few times I've tried 13 he complains about the pressure? Thanks as always for answering my questions.

[DoriC]

Interesting. My Neurologist/Sleep Doctor said that they prefer straight CPAP at Vanderbilt Medical Center. I find it interesting that not only have I gotten my best numbers to date by using straight CPAP instead of APAP (as I was doing), but I also lowered my pressure and got much better results.

What you say is also interesting. When I asked my sleep doc if I should try CPAP since my sleep tech said, "You sure are sensitive to slight pressure changes! You woke each time I bumped it up." he told me "You have an APAP capable machine. Most people do better on it, so you should as well." Thank God for this site.

Cajun, I can top that! At our first visit the Dr set the auto to 8-18(I remember now that he used hubby's titration of 13 as his guideline). I had already been on this forum for a few weeks and read about "sleep specialists" and was starting to get help from the pros about settings,etc, so I already knew what his answer was going to be, "that's why you have an auto machine, it will find the correct pressure". This forum has been the only reason we kept on going. BTW, I seem to think we've had a similar discussion about this before, I may be wrong.