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ajack wrote:a snore is a flow limitation

then why are they counted separately?

would be more interesting and much more enlightening to actually see charts.
Are you talking about the flow-limitation chart on the S9-Resmed-Device or the events scored? - huge difference.
you simply cannot bring down that chart to a zero-flat-line as the resmed autoset algorithm responds nearly only to that. If it would stay flat-lined around zero your APAP would react as an CPAP. Meaning: doing nothing as there is nothing do to.

Related study on the subject: www*ncbi*nlm*nih*gov/pmc/articles/PMC4792477 (* are points) in figure 1 everything above the blue line would take care (completely) of the flowlimitations.

but the basic question is: to what end do you want to reduce them? Is your sleep really disturbed by them? Do you have lower than should be blood-oxygen?
Or do you just want to reduce that reading without any real necessity?

After all the "crap" xxyzx brought into the discussion:
This might not be THE definition of flowlimitations - might not be true at all - but it is how I understand flowlimitations.

Flowlimitations are the difference or the distortion of the (currrent) breath compared to a perfect breath. Look at RobySue's Beginners Guide for SH - Point 10 or 11. There is a great picture on snoring and flowlimitations.
Flowlimitations can be simplified by just looking at the peaks from the breaths compared to the estimated peak values from a perfect breath. (simplified! - theres a bit more to it)

Snoring therefore by definition is a flowlimitation but so is an obstructive hypopnea and in the end the same is true is for an apnea.
But it stays complete and utter bullshit to call a hypopnea a flowlimitation. There really are central hypopneas (just because ResMed does not make a difference there, does not mean they don't exist!) - by definition during a central hypopnea there is no flowlimitation, because in that case it would be an obstructive hypopnea.
Calling snoring a flowlimitation is not in the same category wrong as hypopnea but not right either way. (otherwise you can call an apnea also a hypopnea!)

You can have flowlimitations on inhale and / or on exhale. If you see them on exhale it is the time to get yourself checked up for COPD! (really! and you might want to consider tri-level treatment as for COPD the PEEP / EEPAP is of the outmost importance)
Flowlimitations can have an impact on blood oxygen levels - albeit very low. Eliminating them can lead to better SPO2 levels - but not necessarily.

EPR / Bi-Level will do something equal - increase the amount of air available for oxygenation. With a constant pressure (as in APAP / CPAP) there is a pressure dependant amount of air that just stays in the lungs and therefore is not available for oxygenation - that is the part that you simply cannot exhale against the pressure. (please note also: we are talking "standard litre" (per minute) - read up on that, if you don't know!)
EPR / BI-Level lower the pressure on exhale so that more air can be exhaled, therefore resulting in a higher gas exchange in the lungs.
BUT: there are two ways to achieve gas exchange in the lungs: 1. breath faster 2. breath slower but deeper - both do the same regarding oxygenation.

So, EPR / Bi-Level can reduce the flowlimitations "on paper" as (for the sake of simplicity) during inhale some more air is 'pushed' into the lungs and on exhale 'sucked out'. (sucked out is completely wrong - I just used it for simplicity)
But I seriuosly have my doubts that this actually improves sleep quality for a (otherwise!) "healthy" person - it might look like that on the charts but most (or at least some) of the reduction in flowlimitations might just be the systematical measurement error. It definitely increases oxygenation and definitely stabilizes the flow (in regard to a perfect breath) but to what end?
As the amount of air increases you might end up having more central events (hypopneas for starters) and so a more disturbed sleep. (as your brain comes to the conclusion that you have breathed enough)

As already said: would be nice to see some charts to actually know and understand what exactly it is you are talking about and what you want to achieve.

palerider wrote:

ajack wrote:a snore is a flow limitation

then why are they counted separately?

google it and get back to me. The obstruction from the snore would be a flow limitation

ajack wrote:

palerider wrote:

ajack wrote:a snore is a flow limitation

then why are they counted separately?

google it and get back to me. The obstruction from the snore would be a flow limitation

I think that your blanket statement may be a bit of an oversimplification.

https://www.youtube.com/watch?v=-gie2dhqP2c

A 50% difference is not significant?? What planet were you born on?? I would like to see a citation for that one too. So far no citations. Whassup?

Flow limitations do not make up part of AHI and flow limitations can occur without being followed by apneas.


correct. and are a problem, in and of themselves.

Incorrect!! What problem do they cause? They are a precursor to a problem.

palerider wrote:I think that your blanket statement may be a bit of an oversimplification.

https://www.youtube.com/watch?v=-gie2dhqP2c

Good link. I have had that video saved for several years now.

Even though that video is a few years old (uploaded 10-26-2011), it provides the "distinctions" that people need to understand Re Flow Limitations, etc.

WickedLoki wrote:

Flow limitations do not make up part of AHI and flow limitations can occur without being followed by apneas.


correct. and are a problem, in and of themselves.

Incorrect!! What problem do they cause? They are a precursor to a problem.

well, pardon me for agreeing with you... won't happen again.

to put it simply, flow limitations increase the effort of breathing and reduce the restfulness of sleep.

try breathing through a straw for a while, see how you feel.

I started this thread to try to determine which machine would best deal with my Flow Limitations.

So, call me stupid, but I will strive to continue that discussion.

I have Flow Limitations.
So, what machine would best deal with my Flow Limitations? And why?

AirCurve 10 S
AirCurve 10 VAuto
AirSense 10 AutoSet For Her - since it is my understanding that it deals better with Flow Limitations than the AirSense 10 AutoSet

I am currently using a ResMed S9 AutoSet.

A little more research convinces me that you are correct. My mistake. Strike that comment.

@StuUnderPressure that mostly depends on your flowlimitations.

If we could see some charts one could advice a machine.

StuUnderPressure wrote:I started this thread to try to determine which machine would best deal with my Flow Limitations.

So, call me stupid, but I will strive to continue that discussion.

I have Flow Limitations.
So, what machine would best deal with my Flow Limitations? And why?

AirCurve 10 S
AirCurve 10 VAuto
AirSense 10 AutoSet For Her - since it is my understanding that it deals better with Flow Limitations than the AirSense 10 AutoSet

I am currently using a ResMed S9 AutoSet.

Guest wrote:@StuUnderPressure that mostly depends on your flowlimitations.

If we could see some charts one could advice a machine.

Stu, I think Guest's comment is reasonable. What makes your think any of the machines you mentioned would help you deal with flow limitations better than your S9?
I do think ResMed does a better job, graphically, depicting flow limitation than do some other brands, such as Respironics.
Anecdotally and for your consideration:
I have found that the ResMed auto machine algorithm (S9 in particular) responds with an increase in pressure at a flow limitation level of 0.05 and above.
Further, I have found that a soft cervical collar tends to reduce (my) flow limitations when employed with a FFM.
I have experienced the most dramatic reduction in Flow Limitation by switching to a nasal pillow mask, the P10. With the P10, my Flow limitations average around 0.03, down from an average of about 0.10 with a FFM.
BTW, I think the Dr you couldn't remember the name of is Dr Steven Park, sypark, http://doctorstevenpark.com/

I have not saved the data from my SD card in quite a while.

I will accumulate data for a few days & then post a Flow Limitations graph from the ResScan Software

THANKS for all who contributed useful information.

StuUnderPressure wrote:I started this thread to try to determine which machine would best deal with my Flow Limitations.

So, call me stupid, but I will strive to continue that discussion.

I have Flow Limitations.
So, what machine would best deal with my Flow Limitations? And why?

AirCurve 10 S
AirCurve 10 VAuto
AirSense 10 AutoSet For Her - since it is my understanding that it deals better with Flow Limitations than the AirSense 10 AutoSet

I am currently using a ResMed S9 AutoSet.

ok, you're stupid. (KIDDING!)

of that list, the AC10Vauto gives you the most *options* for treating, and the AC10S the least.

the AC10vauto is ... for all intents and purposes, a more capable and versatile version of the autoset, offering more control over when it switches to IPAP, as well as more pressure support (difference in base and inhale pressure) than the autoset or autoset for her. plus, it's auto adjusting, which the S isn't.

StuUnderPressure wrote:I started this thread to try to determine which machine would best deal with my Flow Limitations.

So, call me stupid, but I will strive to continue that discussion.

I have Flow Limitations.
So, what machine would best deal with my Flow Limitations? And why?

AirCurve 10 S
AirCurve 10 VAuto
AirSense 10 AutoSet For Her - since it is my understanding that it deals better with Flow Limitations than the AirSense 10 AutoSet

I am currently using a ResMed S9 AutoSet.

we still don't know what you are defining as flow limitation. A true flow limitation is treated with more pressure to open up the throat. If you are using the sleepyhead graph as a source.

palerider wrote:

ajack wrote:

palerider wrote:

ajack wrote:a snore is a flow limitation

then why are they counted separately?

google it and get back to me. The obstruction from the snore would be a flow limitation

I think that your blanket statement may be a bit of an oversimplification.

https://www.youtube.com/watch?v=-gie2dhqP2c

well I was going for simple. The video at 1:12 tells it and saves posting a technical study, flow limitation comes before snore and apnea comes after snore, as the airway narrows, but snore and apnea are types of flow limitation, as shown