?'s on flow limitation

allergyridden · Post by **allergyridden** » Fri Nov 23, 2007 9:46 pm

I woke up this morning feeling crappy. When I checked my daily events the flow limitation was 2.9. My leak rate was up at 41 usually 30, probably because the increase in pressure was giving me puffy cheeks. My Ipap is usually 8 or 9, was 11 most of last night. Epap usually 6 was 8 most of the night. OA was 0.2, h 0.7.
Can someone explain what the difference is between flow limitation & hypopnea? They're both partial closings, is that correct? What would cause all of them to happen all in one night? I guess what I'm asking is does any certain thing trigger them? Could Gerd be a factor?
I've spent all night with my foggy brain trying to find info on flow limitation in previous posts.
Thanks,
Sandie

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CPAPopedia Keywords Contained In This Post (Click For Definition): Hypopnea

Wulfman · Post by **Wulfman** » Sat Nov 24, 2007 9:32 am

The following are the definitions from the glossary in the Encore Pro "Help" file......if you have Encore Pro, you can find them (and lots of other things) there, too.

I've always joked that a Flow Limitation was a Hypopnea "wannabe".....but never made it.

Den

Flow Limitation:
A partial obstruction of the airway as detected by a change in the shape of the flow signal.

Hypopnea:
A hypopnea is indicated if there is approximately 40% reduction in airflow for a duration of between 10 and 60 seconds, compared to the average airflow over an extended period of several minutes. Following a reduction in airflow, the therapy device must see two recovery breaths in order to label the event as a potential hypopnea.

Apnea:
An apnea is indicated if there is an 80% reduction in airflow for 10 seconds compared to the average airflow over an extended period of several minutes or if there is no airflow detected for 10 seconds.

.

allergyridden · Post by **allergyridden** » Sat Nov 24, 2007 10:12 pm

Thanks Wulfman. Still not sure why I had so many of them. It took some looking, but I finally found the glossary. Thanks for pointing that out.

Snoredog · Post by **Snoredog** » Sun Nov 25, 2007 12:25 am

FL's are generally not scored since they usually don't result in reduced oxygen levels..,

A Hypopnea is a reduction in flow of >50% lasting 10 seconds or longer with an associated drop in oxygen level of at least 3% from baseline,

So a Flow Limitation is anything less than what it takes to become a Hypopnea.

The Remstar & 420e machines score FL's on their reports.

Wulfman · Post by **Wulfman** » Sun Nov 25, 2007 11:09 am

As I said.....what I posted was from the Encore Pro definitions.....and may be the way it's scored from the sensors in the PAP machines.
I just wanted to post the following to show that there (apparently) are variations in the way they're defined by the medical community and in Wikipedia.

Den

http://www.medicinenet.com/sleep_apnea/article.htm
A hypopnea is a decrease in breathing that is not as severe as an apnea. So, if normal breath airflow is 100% to 70%, a hypopnea is 69% to 26% of a normal breath. Like apneas, hypopneas are associated with a 4% or greater drop in the saturation of oxygen in the blood and usually occur during sleep. Also like apneas, hypopneas usually disrupt the level of sleep. A hypopnea index (HI) can be calculated by dividing the number of hypopneas by the number of hours of sleep.

http://www.emedicine.com/neuro/topic419.htm
Hypopnea is defined very differently at different sleep centers; however, according to a recent consensus statement, hypopnea is a 30% or greater reduction in flow associated with a 4% drop in oxygen saturation. Many centers also score a hypopnea if a decrease in flow is associated with an arousal (see Media files 7-8.).

http://en.wikipedia.org/wiki/Hypopnea
In the diagnosis and treatment of sleep disorders, a hypopnea event is not considered to be clinically significant unless there is a 50% (or greater) reduction in flow and an associated 3% (or greater) desaturation in the person's O2 levels for 10 seconds or longer, or if it results in arousal or fragmentation of sleep.

Wulfman · Post by **Wulfman** » Sun Nov 25, 2007 11:15 am

allergyridden wrote:Thanks Wulfman. Still not sure why I had so many of them. It took some looking, but I finally found the glossary. Thanks for pointing that out.

Could it be "positional"? Sleeping on your back?.....chin tucked too close to your chest (cutting down breathing volume)?

Don't know......

Den

allergyridden · Post by **allergyridden** » Sun Nov 25, 2007 11:47 am

Geez, they don't seem to agree on percentage.
I'm still wondering about acid reflux causing swelling. I'm still having flow limitation that is higher than usual. So I'm trying meds every day to see what that does. (for the reflux)
I'm a side sleeper, but do sometimes wake up on my back. I do know I slept on my side almost all night last night, I nearly blew George out of bed with the air from the vent. I'll remember that when I'm mad at him!
It sure makes you wonder how anyone is supposed to get good results without the software. I would be feeling bad with no idea why! You would really think the Medical Professionals would insist on their patients having software & data capable machines. I could be running back to a Dr with complaints all the time!
I appreciate the feedback from both of you!

Wulfman · Post by **Wulfman** » Sun Nov 25, 2007 11:58 am

allergyridden wrote:Geez, they don't seem to agree on percentage.
I'm still wondering about acid reflux causing swelling. I'm still having flow limitation that is higher than usual. So I'm trying meds every day to see what that does. (for the reflux)
I'm a side sleeper, but do sometimes wake up on my back. I do know I slept on my side almost all night last night, I nearly blew George out of bed with the air from the vent. I'll remember that when I'm mad at him!
It sure makes you wonder how anyone is supposed to get good results without the software. I would be feeling bad with no idea why! You would really think the Medical Professionals would insist on their patients having software & data capable machines. I could be running back to a Dr with complaints all the time!
I appreciate the feedback from both of you!

That's one of the issues that makes my blood boil. Yeah, there are lots and lots of people who couldn't care less about the "inner workings" of their therapy.....and that's their perogative. But, the "money grubbers" who hand out the cheapest stuff to maximize their profits, don't even give the users a chance to succeed. I hope the day when only data-capable machines are manufactured is not far away. (but I'm not holding my breath on that one)

Den

sharon1965 · Post by **sharon1965** » Sun Nov 25, 2007 12:15 pm

I hope the day when only data-capable machines are manufactured is not far away. (but I'm not holding my breath on that one)

but den, if you did, would that be an 80% reduction in airflow or a 40% reduction?

Wulfman · Post by **Wulfman** » Sun Nov 25, 2007 12:22 pm

sharon1965 wrote:
I hope the day when only data-capable machines are manufactured is not far away. (but I'm not holding my breath on that one)
but den, if you did, would that be an 80% reduction in airflow or a 40% reduction?

HA! Good point, Sharon. I DID say that I was NOT going to hold my breath.
On the other hand, if that happened, it would probably be a 40 - 80% reduction of PROFITS for the manufacturers and DMEs....
Cry me a river.....

Den

Wulfman · Post by **Wulfman** » Sun Nov 25, 2007 12:24 pm

Afterthought: I've been saying for a long time, that if the manufacturers would limit their product lines and ONLY make data-capable machines (APAPs - because they can be used in multiple modes), they would actually INCREASE their profits.

Den

DreamStalker · Post by **DreamStalker** » Sun Nov 25, 2007 12:32 pm

Wulfman wrote:Afterthought: I've been saying for a long time, that if the manufacturers would limit their product lines and ONLY make data-capable machines (APAPs - because they can be used in multiple modes), they would actually INCREASE their profits.

Den

Yea ... but it would also make it harder for the DME's to take advantage of sleep-deprived victims to line their own greedy pockets with the fat of our insurance premiums ... not to mention, our drive-by DME Guest(s) would have a cow with no one to discourage from getting an APAP.

sharon1965 · Post by **sharon1965** » Sun Nov 25, 2007 12:33 pm

and less money being made by docs...no more bringing people back for repeated psg's

Wulfman · Post by **Wulfman** » Sun Nov 25, 2007 12:52 pm

With as many millions of people who supposedly (will) need this therapy (as predicted by the medical professionals), they're going to need to streamline this therapy assembly line to be able to get to all of those folks.

On another note, they're going to have to properly train those people who would be prescribing and handing out the APAPs. After all, the wide open settings of 4 - 20 cm. are NOT the best for "good" therapy.

Den