baseline air flow rate determination?

[Sirca]

if a hyopnea, for example, is defined as a 50% reduction in air flow for > 10 seconds, how does the machine determine the baseline flow that is "normal"? is it a relative thing, i.e., determined by the air flow the pneumotach sees when the mask is first connected?

[SleepTechulous]

Apap machines are wildly inaccurate in their determination of obstructive or central events. They should only be used for novelty purposes sadly. I think that we are still a good ten or fifteen years away from having devices which are capable of recognizing actual events. Until then it is all guess work.

[KatieW]

I think this is covered in this:

viewtopic/t55680/APAP-webinars--new-wit ... tml#unread

[elena88]

Apap machines are wildly inaccurate in their determination of obstructive or central events. They should only be used for novelty purposes

Oh I agree, we should just use them for entertainment at childrens birthday parties..

[Sirca]

I think this is covered in this:

viewtopic/t55680/APAP-webinars--new-wit ... tml#unread

Thank you, Katie. I'm familiar with these webinars. If they use a 3 minute moving average (or whatever) of air flow, but you fall asleep and into apnea quickly, that would seem to set a falsely low flow for the algorithms.

[Sirca]

Apap machines are wildly inaccurate in their determination of obstructive or central events. They should only be used for novelty purposes sadly. I think that we are still a good ten or fifteen years away from having devices which are capable of recognizing actual events. Until then it is all guess work.

In that case, I guess I should breath as normally as possible for the first few minutes after I first connect the machine at night. Then it would (presumably) have a useful baseline to defend.

[M.D.Hosehead]

SleepTechulous seems familiar somehow.

[blusaber]

SleepTechulous seems familiar somehow.

Why yes he does and as such joins the banned calist on my foe list......Problem solved

Nothing like a good first impression

Gary

[Sirca]

SleepTechulous seems familiar somehow.

not helpful

[Sirca]

SleepTechulous seems familiar somehow.

Why yes he does and as such joins the banned calist on my foe list......Problem solved

Nothing like a good first impression

Gary

also not helpful

[Sirca]

I'm not depending on the APAP algorithm for therapy. I'm using the APAP machine in CPAP mode and looking at the data and wondering what baseline it's using to score my apneas and hypopneas.

My main criteria for successful therapy are how I feel during the day, and my nocturnal SpO2. The machine's scoring is secondary, but I'm still curious about it.

[Goofproof]

Sounds like a good cop - bad cop act for echo effect of don't matter.

Not Helpful Jim

Too bad neither one is sure of their gender, a dead give away!

[ozij]

if a hyopnea, for example, is defined as a 50% reduction in air flow for > 10 seconds, how does the machine determine the baseline flow that is "normal"? is it a relative thing, i.e., determined by the air flow the pneumotach sees when the mask is first connected?

Depends on the machine's algorithm. Varies from company to company.

Examples from Respironics: http://sleepapnea.respironics.com/techn ... rithm.aspx
http://sleepapnea.respironics.com/techn ... apnea.aspx

Example from Resmed:
https://5faacd0c97cf0d23c6dc-064f3cd61b ... -sheet.pdf

[jonquiljo]

SleepTechulous seems familiar somehow.

Why yes he does and as such joins the banned calist on my foe list......Problem solved

Oh, he's been back in at least one other incarnation. But he can't do much with one-liners.

[elena88]

Amy you are so darn cute!