Pdf's of Respironics Patents

[derek]

I have converted the two Respironics patents that Mikesus referred to earlier to pdf files (complete with images). You can download them:

Respironics APAP Patent Application 49 pages (3 Mbytes)

Respironics Apnea/Hypopnea Detection Patent Application 14 pages (1 Mbyte)

derek

[ozij]

Thanks!
O.

[Mikesus]

0159] H. Variable Breathing Control Layer

[0160] The Auto-CPAP controller, which is described in the next section, relies on the ability to trend the steady rhythmic breath patterns associated with certain stages of sleep. When a patient is awake, in REM sleep, or in distress, breathing tends to be more erratic and the Auto-CPAP trending becomes unstable. It is, therefore, important to interrupt the Auto-CPAP controller if the patient's breathing pattern becomes too variable. In essence, the variable breathing control layer keeps the Auto-CPAP control layer from being too erratic.

[0161] Referring back to FIG. 2, the variable breathing control layer, which is assigned a seventh (7th) priority, includes a variable breathing detector 270, a variable breathing monitor 272, and a variable breathing controller 274. As described in greater detail below, the variable breathing control layer performs statistical analysis on the scatter of the trended weighted peak flow data to detect unstable breathing patterns or abrupt changes in patient response. When activated, variable breathing control module 274 takes priority over the auto-CPAP controller, so that when a valid variable breathing indication is provided by variable breathing monitor 272, control of the pressure support system is turned over to the variable breathing controller. In short, activation of variable breathing control module 274 interrupts the operation of the auto-CPAP controller when breathing becomes unstable and appropriately manages any necessary pressure changes.

I wonder if this is what is causing Loonlvr's strange episodes. If the breathing is considered variable, then no pressure rises can occur. Hmmmmm....

[Mikesus]

Bump for replies...

[wading thru the muck!]

Mike,

This would sure explain a lot regarding some people who just seem to get erratic results from their auto-pap. Have you seen any studies in those searches you do at that place called "The Internet?" regarding erratic breathing patterns. Could this possibly be a "central" or neurologically caused condition. I wonder if a GOOD sleep lab could diagnose this type of erratic breathing disorder if instructed to watch for it?

Good pick-up on that potential cause of unexplained auto-pap results.

Am I to assume that this new patent attempts to detect these erratic breathing patterns and modifies the auto-pap function to correctly treat them?

[Mikesus]

Am not sure. And I don't know if you could find that from their patent... I would suspect that a PSG should identify it quite easily... But the PSG is only as good as the people reading it.

Interesting nonetheless...

[-SWS]

Bump for replies...

There's absolutely no doubt in my mind that some patients with highly erratic breathing will throw this particular variable-breathing detection controller for a loop, Mike. This variable-breathing detection controller also explains why some people have posted that they unsuccessfully tried to fool their Remstar Auto into triggering on simulated apneas by intentionally halting their breath while still awake: while wide awake and experimenting they wouldn't have presented that highly regular breathing pattern characteristic of slumber.

As to this particular algorithmic controller explaining loonlvr's response. Weren't each of his "pressure response sit-out sessions" preceded by exactly three pressure increments? If so, I believe his response fits the NR detection/response routine more than this variable-breathing detection/response routine, which would not always be preceded by exactly three pressure increments above 8 cm.

[wading thru the muck!]

Is this the patent for the current REMstar auto or for a new yet to be released model?

[Mikesus]

Believe it is the current model.

SWS - The problem is that if variable breathing occurred in between it would stop responding. So, it is possible that it triggered an event, variable breathing followed by a stabilization, followed by an event. Etc. On face it would appear like a NR situation, but not all of the events he had were scored that way. Make sense?

[wading thru the muck!]

...activation of variable breathing control module 274 interrupts the operation of the auto-CPAP controller when breathing becomes unstable and appropriately manages any necessary pressure changes.

Sounds to me like it is suppose to be able to handle the erratic breathing and is able to "appropriately manage any necessary pressure changes."

[-SWS]

I agree Wader. If you look at figure 13 on this patent, what you just described is handled during region 320 of the variable-breathing contoller's take over from the Auto CPAP controller. At this initial take over phase, this particular algorithmic controller may perform a variety of "necessary" pressure adjustments to normalize a "best fit" target air flow for the patient.

The next variable-breathing controller phase is region 322, in which the pressure is either maintained, or dropped a tad, then maintained for 15 minutes. Finally the last variable-breathing controller phase is region 324, in which a ramp down always occurs.

Region 324 is what makes loonlvr's graphs a definite "no fit" for this particular variable-breathing controller, Mike. Loonlvr's pressure response "sit out" sessions were always followed by a ramp up, whereas this controller's final region always entails a pressure ramp down process.

[Mikesus]

Good catch SWS.

[Justin Case]

I just did a search for the keyword "variable breathing" since I am using Encore software and this thread came up.

My reading is around 30-33% variable breathing. I cannot get my AHI below 8.9 using an Auto PAP (CFLEX)

Can anyone provide any insight if my variable breathing is the reason why my apneas are not being controlled?

[Goofproof]

You are listed as a guest, you can't post the equiptment you use and we don't know how you use it. So we are supposed to guess whats going on. Your breathing numbers are close to what I run and my AHI is under 1.0, so I would not say that's your problem. I don't worry about V.B. stats , I can't change them, I worry about AHI, pressure, snore, and time spent in apnea. Jim

And most important, LEAKS!

_________________

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

[Justin Case]

The equipment I am using is the Remstar Pro Auto CFLEX with Mirage Activa Mask.

How does the type of [auto] machine make a difference?
What more info do you need?

I worry about the VB and as I understand it, maybe a BIPAP (BFLEX auto) is what I really need, not just want?