"please keep me updated about oximeters "
Sleep Apnea Forum Bringing Power to the Patient
New? Free Sign Up
Then check our Welcome Center to a Community Caring about Sleep Apnea diagnosis and Sleep Apnea treatment:
CPAP machines, Sleep Apnea surgery and dental appliances.
CPAP Supplies
Latest Activity
AHI vs. AI and HI
I was going to post in another thread about the usefulness of AHI, but I thought I'd start a separate one for this question.
My CPAP stats are pretty consistent, in that the AI numbers are fairly low, in the range of 0.0 to 0.5 on a typical night, though it's gone as high as 1.7.
On the other hand, the HI numbers are usually much higher, in the range of 5.0 to 11.5.
I can't seem to find any reason for the hugher HIs.
I originally thought it was due to leaks, which typically are around 0.4 to 0.6, but that doesn't seem to be the case.
Over the years I've taught myself to do deep breathing, and to slow my breathing down when I go to sleep, in order to relax.
Does anyone have an idea if this HI range is normal, or high?
If it's high, is there an explanation as to why it is high?
On a (possibly?) unrelated note, in the last week I've been feeling more tired during the day. I've started with a new mask, but I'm not sure if that has anything to do with it.
Thanks!
Views: 1564
Replies to This Discussion
-
Permalink Reply by Judy on
-
*giggle* YOU are so baaaaaaaaaad, jnk. So very, very bad. LOL Scheming to take advantage of our Rock HInkle. Fer shame!!
-
Permalink Reply by Andy on
-
Another Interesting information is that ResMed S8 NOT responds to apneas when the pressure is above 10 cmH2O
I hate to complicate this...
So, if a machine is set to 10, then it IS responding to HI? And if it's >10, then it IS NOT responding to HI?
This stuff is definitely confusing!
This information might help clarify it. It's from the post "Resmed's Development of the AutoSet" Posted by Judy on July 12, 2009 at 11:24am .
Why doesn’t ResMed's AutoSet respond to hypopnoea? When you are lying quietly awake, or when you first go to sleep, or when you are dreaming, you can have hypopneas (reductions in the depth of breathing) which are nothing to do with the state of the airway. For example if you sigh, which you do every few minutes, you usually have a hypopnea immediately afterwards. This can also happen if you have just rolled over and are getting settled, or if you are dreaming. And the annoying thing is that
when you are on CPAP, this tendency to have what are called central hypopneas - hypopneas that are nothing to do with the state of the airway - is increased. If you make an automatic CPAP device that responds to hypopneas, you will put the pressure up to the maximum while the patient is awake.
Do you think there is a misconception clinically that all hypopneas should be treated ?For simple obstructive sleep apnea, central hypopneas should not be treated. They are not a disease. Everyone has them. And they don’t go away with CPAP. There is a rare and important exception: central hypopneas due to heart disease. This is called Cheyne-Stokes breathing. CPAP does help with that.
Why doesn’t ResMed's AutoSet respond to apnea above 10 cmH2O in pressure?
I mentioned before that the higher the pressure, the more central hypopneas you will have. At a pressure somewhere around 10 cmH2O, the central hypopneas become central apneas. On the other hand, the vast majority of obstructive apneas are already well controlled by 10 cmH2O, and we are only fine tuning using snoring and flattening. So it is a pretty good bet that if the pressure is already above 10 cmH2O, any apneas are most likely
central, and you should leave them alone (except in patients with central apneas due to heart failure). But if the pressure is below 10 cmH2O, most apneas will be obstructive and you should put the pressure up. There’s nothing magical about 10 cmH2O, it’s just a good place to put the line in the sand.
-
Permalink Reply by Henning on
-
Andy,
I think it is very simple.
If your pressure is high enough to treat your apneas, so it will always be high enough to treat your Hypopneas.
That is why ResMed says you only have to worry about your apneas.
I agree with you, I don't understand why they count HI if they are treatet.
Henning
-
-
Henning said:Andy,
I think it is very simple.
If your pressure is high enough to treat your apneas, so it will always be high enough to treat your Hypopneas.
That is why ResMed says you only have to worry about your apneas.
I agree with you, I don't understand why they count HI if they are treatet.
Henning
OK, that makes sense.
But here's what I get out of the citation I made above:
When you are on CPAP, this tendency to have what are called central hypopneas - hypopneas that are nothing to do with the state of the airway - is increased. If you make an automatic CPAP device that responds to hypopneas, you will put the pressure up to the maximum while the patient is awake. For simple obstructive sleep apnea, central hypopneas should not be treated...And they don’t go away with CPAP.
...I mentioned before that the higher the pressure, the more central hypopneas you will have. At a pressure somewhere around 10 cmH2O, the central hypopneas become central apneas...So it is a pretty good bet that if the pressure is already above 10 cmH2O, any apneas are most likely central, and you should leave them alone...But if the pressure is below 10 cmH2O, most apneas will be obstructive and you should put the pressure up.
So, here's my interpretation of this:
For simple obstructive sleep apnea, central hypopneas should not be treated.
At around 10cmH20, central hypopneas become central apneas.
Below 10, just assume the assumption is that apneas are obstructive, and increase the pressure.
At or above 10, any apneas are likely to be central, so leave them alone.
Now, that makes me wonder why the pressure would ever be set above 10, since the apneas still occurring above 10 are typically central, and should not be treated.
-
-
Hi Jeff,
Thanks for continuing this discussion, and for lending more detail.
Being an engineering/technical type, I'm as much interested in the stuff going on behind the scenes, as I am in feeling better!
I've been wondering how my S8 would react if it were in auto mode. Would it bump the pressure any higher than it is now? Or would it spend the night "hunting" for the "right" pressure?
Maybe one day I'll switch it over to auto, and see what it does!
-
Permalink Reply by Renee on
-
Hello Jeff ~
Thanks for the simply laid out suggestion.
Best,
Renee
j n k said:The way you use the trending information from a ResMed S8 to dial into the right pressure in CPAP mode for simple OSA is that you first find the pressure that gets your AI below 1.0. That has your apneas treated. You leave it at that pressure for two weeks and note your AI and HI for those two weeks. Then you raise your pressure (a cm or less) and see what that does for your numbers for two weeks. If your HI goes down AND YOU NOTICE YOU FEEL BETTER, you figure you have moved your pressure in the right direction. If your AI or HI goes up with that rise in pressure, or if you don't feel any better, you move the pressure back down, confident you are as high as you need to go.
As long as those moves are made scientifically and carefully, preferably with the approval and participation of your doctor, you are dialing in the ideal pressure. You don't want to move pressure all over the board willy-nilly, But a few tweaks to see if it improves your numbers AND HOW YOU FEEL can't hurt.
That is my position as a self-titrating patient whose doc doesn't mind if I tweak a bit.
(1) Gradual move, (2) give it a few weeks, (3) watch the numbers and how you feel. That is the game. With a Respironics, give equal weight to AI and HI. With a ResMed, give more weight to the AI and don't fret much about the HI. That is my impression, anyway, based on what I've experienced and read on the boards from other users.
jeff
-
-
Hello to whomever ~
Regarding: "Now, that makes me wonder why the pressure would ever be set above 10, since the apneas still occurring above 10 are typically central, and should not be treated."
________________________________________________________
If the apneas still occurring above 10 are typically central, and should not be treated - why would anyone ever have their pressure above 10?
I use the ResMed S-8 Elite II and monitor my AI and HI daily. I changed my pressure just 3 nights ago from 12 to 14 primarily to try to lower my AI and my AI did lower from 1.5 to 0.5 and my HI also lowered from 3.2 to 2.2 but I agree with monitoring the HI more for the trend.
However, although my AIs are registering lower at the increased pressure - does the S-8 only register the OSAs - and NOT CENTRAL apneas? And, so, could I have decreased OSAs - BUT, INCREASED CENTRAL apneas?
Thanks for any thoughts.
Best,
Renee
_____________________
Now, that makes me wonder why the pressure would ever be set above 10, since the apneas still occurring above 10 are typically central, and should not be treated.
Andy said:Henning said:Andy,
I think it is very simple.
If your pressure is high enough to treat your apneas, so it will always be high enough to treat your Hypopneas.
That is why ResMed says you only have to worry about your apneas.
I agree with you, I don't understand why they count HI if they are treatet.
Henning
OK, that makes sense.
But here's what I get out of the citation I made above:When you are on CPAP, this tendency to have what are called central hypopneas - hypopneas that are nothing to do with the state of the airway - is increased. If you make an automatic CPAP device that responds to hypopneas, you will put the pressure up to the maximum while the patient is awake. For simple obstructive sleep apnea, central hypopneas should not be treated...And they don’t go away with CPAP.
...I mentioned before that the higher the pressure, the more central hypopneas you will have. At a pressure somewhere around 10 cmH2O, the central hypopneas become central apneas...So it is a pretty good bet that if the pressure is already above 10 cmH2O, any apneas are most likely central, and you should leave them alone...But if the pressure is below 10 cmH2O, most apneas will be obstructive and you should put the pressure up.
So, here's my interpretation of this:
For simple obstructive sleep apnea, central hypopneas should not be treated.
At around 10cmH20, central hypopneas become central apneas.
Below 10, just assume the assumption is that apneas are obstructive, and increase the pressure.
At or above 10, any apneas are likely to be central, so leave them alone.
Now, that makes me wonder why the pressure would ever be set above 10, since the apneas still occurring above 10 are typically central, and should not be treated.
-
Permalink Reply by RockRpsgt on
-
I do not agree. Central apneas are rare. Central hypopneas are practically myths they are seen so little. It takes a very trained eye to detect these events. without respiratory effort monitoring it would be impossible. The only way to tell what type of events you are having is with a PSG. Home testing nor the PAP algorithms are not sufficient to accurately identify events 80% of the time. I would also add that pressure induced CSA is not as common as many of you think. CPAP will fix CSA more often then it will cause it. Events above 10cm are NOT always or typically central in nature.
I also disagree with the point that centrals should not be treated. The better statement would be that sometimes central apnea is untreatable. Regardless of the reason for your central apnea steps should always be taken to eliminate them if possible. Steps that should include your physician.
Renee said:Hello to whomever ~
Regarding: "Now, that makes me wonder why the pressure would ever be set above 10, since the apneas still occurring above 10 are typically central, and should not be treated."
________________________________________________________
If the apneas still occurring above 10 are typically central, and should not be treated - why would anyone ever have their pressure above 10?
I use the ResMed S-8 Elite II and monitor my AI and HI daily. I changed my pressure just 3 nights ago from 12 to 14 primarily to try to lower my AI and my AI did lower from 1.5 to 0.5 and my HI also lowered from 3.2 to 2.2 but I agree with monitoring the HI more for the trend.
However, although my AIs are registering lower at the increased pressure - does the S-8 only register the OSAs - and NOT CENTRAL apneas? And, so, could I have decreased OSAs - BUT, INCREASED CENTRAL apneas?
Thanks for any thoughts.
Best,
Renee
_____________________
Now, that makes me wonder why the pressure would ever be set above 10, since the apneas still occurring above 10 are typically central, and should not be treated.
Andy said:Henning said:Andy,
I think it is very simple.
If your pressure is high enough to treat your apneas, so it will always be high enough to treat your Hypopneas.
That is why ResMed says you only have to worry about your apneas.
I agree with you, I don't understand why they count HI if they are treatet.
Henning
OK, that makes sense.
But here's what I get out of the citation I made above:When you are on CPAP, this tendency to have what are called central hypopneas - hypopneas that are nothing to do with the state of the airway - is increased. If you make an automatic CPAP device that responds to hypopneas, you will put the pressure up to the maximum while the patient is awake. For simple obstructive sleep apnea, central hypopneas should not be treated...And they don’t go away with CPAP.
...I mentioned before that the higher the pressure, the more central hypopneas you will have. At a pressure somewhere around 10 cmH2O, the central hypopneas become central apneas...So it is a pretty good bet that if the pressure is already above 10 cmH2O, any apneas are most likely central, and you should leave them alone...But if the pressure is below 10 cmH2O, most apneas will be obstructive and you should put the pressure up.
So, here's my interpretation of this:
For simple obstructive sleep apnea, central hypopneas should not be treated.
At around 10cmH20, central hypopneas become central apneas.
Below 10, just assume the assumption is that apneas are obstructive, and increase the pressure.
At or above 10, any apneas are likely to be central, so leave them alone.
Now, that makes me wonder why the pressure would ever be set above 10, since the apneas still occurring above 10 are typically central, and should not be treated.
-
-
Hello Rock ~
Very well explained - and much appreciated !
Thank you, Rock,
Renee
______________________________________
Rock Hinkle said:I do not agree. Central apneas are rare. Central hypopneas are practically myths they are seen so little. It takes a very trained eye to detect these events. without respiratory effort monitoring it would be impossible. The only way to tell what type of events you are having is with a PSG. Home testing nor the PAP algorithms are not sufficient to accurately identify events 80% of the time. I would also add that pressure induced CSA is not as common as many of you think. CPAP will fix CSA more often then it will cause it. Events above 10cm are NOT always or typically central in nature.
I also disagree with the point that centrals should not be treated. The better statement would be that sometimes central apnea is untreatable. Regardless of the reason for your central apnea steps should always be taken to eliminate them if possible. Steps that should include your physician.
Renee said:Hello to whomever ~
Regarding: "Now, that makes me wonder why the pressure would ever be set above 10, since the apneas still occurring above 10 are typically central, and should not be treated."
________________________________________________________
If the apneas still occurring above 10 are typically central, and should not be treated - why would anyone ever have their pressure above 10?
I use the ResMed S-8 Elite II and monitor my AI and HI daily. I changed my pressure just 3 nights ago from 12 to 14 primarily to try to lower my AI and my AI did lower from 1.5 to 0.5 and my HI also lowered from 3.2 to 2.2 but I agree with monitoring the HI more for the trend.
However, although my AIs are registering lower at the increased pressure - does the S-8 only register the OSAs - and NOT CENTRAL apneas? And, so, could I have decreased OSAs - BUT, INCREASED CENTRAL apneas?
Thanks for any thoughts.
Best,
Renee
_____________________
Now, that makes me wonder why the pressure would ever be set above 10, since the apneas still occurring above 10 are typically central, and should not be treated.
Andy said:Henning said:Andy,
I think it is very simple.
If your pressure is high enough to treat your apneas, so it will always be high enough to treat your Hypopneas.
That is why ResMed says you only have to worry about your apneas.
I agree with you, I don't understand why they count HI if they are treatet.
Henning
OK, that makes sense.
But here's what I get out of the citation I made above:When you are on CPAP, this tendency to have what are called central hypopneas - hypopneas that are nothing to do with the state of the airway - is increased. If you make an automatic CPAP device that responds to hypopneas, you will put the pressure up to the maximum while the patient is awake. For simple obstructive sleep apnea, central hypopneas should not be treated...And they don’t go away with CPAP.
...I mentioned before that the higher the pressure, the more central hypopneas you will have. At a pressure somewhere around 10 cmH2O, the central hypopneas become central apneas...So it is a pretty good bet that if the pressure is already above 10 cmH2O, any apneas are most likely central, and you should leave them alone...But if the pressure is below 10 cmH2O, most apneas will be obstructive and you should put the pressure up.
So, here's my interpretation of this:
For simple obstructive sleep apnea, central hypopneas should not be treated.
At around 10cmH20, central hypopneas become central apneas.
Below 10, just assume the assumption is that apneas are obstructive, and increase the pressure.
At or above 10, any apneas are likely to be central, so leave them alone.
Now, that makes me wonder why the pressure would ever be set above 10, since the apneas still occurring above 10 are typically central, and should not be treated.
-
-
Hi All,
Thanks for this very lively discussion!
These are very interesting insights and opinions on what's going on, and how I should interpret my HI results...
-
-
Hey Rock ~
Appreciate the mention . . . you have so much goodness in you . . . I am glad to be in your sphere . . .
Thinking all good thoughts of you,
Renee
____________________________
Rock Hinkle said:Hello Renee, Welcome back.
- ‹ Previous
- 1
- 2
- Next ›
© 2024 Created by The SleepGuide Crew.
Powered by
