Interpertion & Accuarcy of the Respironics Display Data

[janp]

I was unable to find previous posts that specifically addressed my questions. So here goes ...

I'm currently using the REMstar Auto|APAP for diagnostics (I've been on the M Plus for 3 months). My husband had asked the doctor's office why I appeared to be having so many APNEA issues while asleep after being prescribed the REMstar Plus set at 6. As you can imagine, The DME has been less than cooperative in sharing data or it's interpretation. I guess I'm not supposed to know what's happening with the machine.

Some of the data is straightforward, ie. Therapy usage, Sessions, Summary Data.

I understand 90% pressure ... but how does it relate to "CmH2o"? Is it simply saying "of air"? Mine is reading 12. The machine's limits are set at 6 and 12.

How do I determine if the System Leak number is within acceptable limits? The mask is Respironic's Nasal ComfortGel (small).

Is the Apnea-Hypox Index a "direct reading" (AHI=20) or is some calculation required for interpretation? I'm reading 7. My sleep study showed an AHI of 14/hr with a Central AHI of 5.

I've been reading the forum for the past week before joining ... I have to say that I'm absolutely amazed and impressed at how much support and information this community provides.

Then of course, how accurate is the displayed information versus that read from the card?

Yes ... once my doctor has all the info he wants and new parameters are established, I do plan on using EncoreViewer to track my sleep therapy. I might feel the need to replace the machine if the data/therapy justifies ... this time out of my own pocket.

Thank you in advance for any guidance you can afford this "newbie".

[SharkBait]

I understand 90% pressure ... but how does it relate to "CmH2o"? Is it simply saying "of air"? Mine is reading 12. The machine's limits are set at 6 and 12.

How do I determine if the System Leak number is within acceptable limits? The mask is Respironic's Nasal ComfortGel (small).

Is the Apnea-Hypox Index a "direct reading" (AHI=20) or is some calculation required for interpretation? I'm reading 7. My sleep study showed an AHI of 14/hr with a Central AHI of 5.

90% pressure is still in cmH2O. I believe it's saying 90% of the time your pressure was at 12 or below. I'm not thrilled with the whole 90% thing, but maybe others can tell you why that's useful...

Your ComfortGel should have a chart showing the vent rate. Find your average pressure for a best guess of what your vent rate should be on that chart, and then subtract from Leak Rate. (Respironics rates are liters per minute, Resmeds are liters per second). In other words with Respironics you are supposed to have quite a bit of "leak" to vent the CO2, but you have to look at the chart for your mask to see if it's too much over that. Your machine will compensate the pressure for some excessive leak, but you still want to get it as close to 0 as possible. I typically sleep withabout a 3 Liter per Minute leak on my mask and it's all good.

Not sure what you mean by direct reading, but AHI is the AI + HI. It's kind of important to get those two numbers broken out because an AHI with 6 AI and 1 HI is quite a bit worse than an AHI of 1 AI and 6 HI.

[SharkBait]

Then of course, how accurate is the displayed information versus that read from the card?

Both sets of data come from the same source. The displayed is a summary, where as the card is holding detail for the last few days. The software is nice so you can see where the Apnea events are occuring, at what pressure, and what leak rate. Very useful.

If you're gonna splurge for the USB reader and software anyway, I think you'd find it useful as you're trying to settle on a titrated pressure.

[DreamStalker]

The system leak depends on the average pressure of the system

http://sleepapnea.respironics.com/PDF/LeakRate.pdf

90% pressure usually refers to APAP mode ... the pressure at which the machine reamined at or above most of the time (specifically 90% of the time since measurements are sampled by the machine on equal time intervals). So, to take care of most of your apnea or hypopnea events, most experts will advise that the 90% pressure value be used as the CPAP mode pressure so that at least 90% of the events will be taken care of.

Since you are sensitive to central type apneas, you would do well to leave your upper or max pressure setting on your APAP as is and if you do change it it may be to lower rather than raise it.

The AHI is the sum of apneas and hyponeas divided by the time in sleep ... an index rate of combined events per hour. The display information from the M series has been know to be suspect. The software is the only way to get really accurate data from the machine.

[Handgunner45]

I've been on the M Plus for 3 months

If the Auto is just a loaner and you will be going back to the Plus after the "diagnostics", do not bother buying the card reader and software. The Plus will only tell you how much you have used the machine....it does not give any usefull data.

[The Texan]

I've been reading the forum for the past week before joining ... I have to say that I'm absolutely amazed and impressed at how much support and information this community provides.

Then of course, how accurate is the displayed information versus that read from the card?



Thank you in advance for any guidance you can afford this "newbie".

I think Respironics itself is wondering about the accuracy of their information. I just participated in a Respironics funded research that is studying that exact question with the M series auto APAP. It was a sleep study being conducted by Shands Hospital for Respironics.

[jules]

The LED data on the respironics machines is poor quality.


I would not want to determine ANYTHING based on it.