Hypopneas ... almost ignored by Resmed

Velbor wrote: . . . there is little justification in implying or suggesting that ResMed "ignores" hypopneas. . . . Velbor

Amen, Velbor.

It is confusing to me when people imply that a machine without an oximeter is supposed to call certain flow limitations hypopneas and not others. How can ANY machine without an oximeter claim to know a hypopnea from a flow limitation? None can, as Arizona-Willie noted. So shall we condemn ResMed for being overly honest in their carefully worded descriptions of what they do, and praise the companies that use sloppier wording?

I say that the machines using the AutoSet algorithm far from ignore hypopneas. If anything, the problem is the exact opposite--they pay too much attention to flow limitation in that they seem to score most any flattened bell-curve as a hypopnea in reporting AHI. But, given a choice, my preference is for oversensitivity in reporting flow limitations. So I ain't complainin'.

I likewise find it confusing when some suggest a machine is bad because it doesn't "react" to an apnea above 10cm. Why react to something you prevent? Isn't that like calling a guy a bad mechanic because his preventative maintenance keeps him from having to work on his car all the time?

If my AI is below 1, why would I complain about what the machine would have hypothetically done had there been some sudden apnea, with no precursors, that 10cm wouldn't have resolved? If that were to happen on a regular basis, my lcd would be telling me about it every mornin'. So I ain't worrying about somethin' that ain't happening!

I'm not trying to defend anyone's algorithm. All the machines could use some improvement, IMO. I just felt like throwing around my uneducated opinion. That's what forums are for, after all!

jnk

jnk wrote:

Velbor wrote: . . . there is little justification in implying or suggesting that ResMed "ignores" hypopneas. . . . Velbor

Amen, Velbor.

It is confusing to me when people imply that a machine without an oximeter is supposed to call certain flow limitations hypopneas and not others. How can ANY machine without an oximeter claim to know a hypopnea from a flow limitation? None can, as Arizona-Willie noted. So shall we condemn ResMed for being overly honest in their carefully worded descriptions of what they do, and praise the companies that use sloppier wording?

I say that the AutoSet algorithm far from ignores hypopneas. If anything, the problem is the exact opposite--it pays too much attention to flow limitation in that it seems to score most any flattened bell-curve as a hypopneas in reporting AHI.

Well said, Velbor and jnk.

Just because there is an "official" (arbitrary) definition of what constitutes a hypopnea for scoring a PSG sleep study does not mean that the manufacturers who make the treatment machines are required to avoid using that handy word to refer to a flow limitation that exceeds whatever (arbitrary) point of diminishing air flow they choose it to mean. Can be different from manufacturer to manufacturer.

jnk, I said that Resmed almost ignores hypopneas not because they don't do anything about them, but because they don't tell us very much about them.

They tell us how long each apnea lasts but they don't give us that info on hypopneas and a hypopnea can be just as damaging as an apnea. If the flow is reduced by 70% for 3 minutes Resmed just calls it a hypopnea but it results in much less air reaching the lungs than a 10 second apnea at 75% air flow restriction.

I just think Resmed should give us more information than they do.

Arizona-Willie wrote:jnk, I said that Resmed almost ignores hypopneas not because they don't do anything about them, but because they don't tell us very much about them. . . . I just think Resmed should give us more information than they do.

Arizona-Willie, I was trying to give Snoredog a hard time, not you. I quoted the good point you made about O2 levels because I think it is often overlooked when some "critique" ResMed's descriptions of what its machines do.

And I agree with your points. ResMed's software doesn't give enough info. I also think the software is overpriced, and it sounds a little clunky, though I've never used it. But I'd better stop before the software-using ResMeders come after me as a turncoat.

RESTED GAL, I sure learn a lot from the balanced, informative way you word things. Thanks for all you do.

jnk

Arizona-Willie wrote: It seems to me that they aren't paying sufficient attention to hypopneas ... they just kinda wave them off with a casual ' oh that's just a hypop '.

Hi Arizona-Willie,

I was just studying my charts looking for a correlation between hypopneas and pressure and it sure is there. So we can at least rest that Resmed has taken care to respond with pressure changes in response to the hypopneas, They may not capture that data and export it to the software but the machines are watching over us.

Dennis