ResScan details - Analysis request

[karthikvprasad]

Hello forum,

With the help of this forum, I was able to figure out how to get my sleep data that's stored on my SD card using the ResScan software.
Here are the results for the last month. Can anyone kindly analyze this and answer a couple of questions I have.
1. Are the Leak numbers very high?
2. If so, does that mean I need a new mask?
3. What are Minute Ventilation and Flow Limitation? What do these numbers indicate?

Summary Details: https://docs.google.com/document/d/1Uc9 ... t?hl=en_US
Detailed Chart for 7/15: https://picasaweb.google.com/lh/photo/7 ... directlink

Thanks a lot!
KP

[robysue]

1. Are the Leak numbers very high?

Leak rates on the summary data are VERY GOOD since the 95% leak rate is 0.0. That means 95% of time the machine was running between June 18 and July 15, it was detecting no unintentional leaks. (Note: The S9's use the mask setting to subtract off an approximate intentional leak rate from the raw data before reporting the leak rate data.)

But the leak graph for July 15 is not very good. Not hideous since it never goes above the RedLine. But the leak rate is bouncing around a fair amount and is in the double digits much of the night.

2. If so, does that mean I need a new mask?

Could be. Or it could be that your mask cushion needs to be replaced. Or you might be having some issues with mouth breathing.

3. What are Minute Ventilation and Flow Limitation? What do these numbers indicate?

Minute ventilation is a measure of how much air you inhale over the course of a full minute. Flow limitation is based on the shape of the individual inspiratory parts of the wave flow---which you can't see until you zoom in on a five minute or smaller window. Flow limitations are thought to indicate an upper airway that is beginning to narrow and is at high risk of collapsing. I don't actually see a Flow Limitation graph in the ones you posted. You did post a FLOW graph. The Flow graph contains a trace of every breath you took with the machine on. It records the rate the air was going into or out of your lungs, measured in L/min if I I recall correctly. The inhales have POSITIVE flow rates and the exhales have NEGATIVE flow rates. So you are inhaling the whole time the Flow curve is above the line marked with a 0 and you are exhaling the whole time the Flow curve is below the line with the 0. At the scale you've provided in your link, the Flow curve really doesn't show any detail. It does show several times when I'd guess that you were restless because of the much higher flow numbers.

Summary Details: https://docs.google.com/document/d/1Uc9 ... t?hl=en_US
Detailed Chart for 7/15: https://picasaweb.google.com/lh/photo/7 ... directlink

Thanks a lot!
KP[/quote]

[Mike6977]

Minute ventilation in normal sleep:

"Breathing is remarkably regular, both in amplitude and frequency in steady NREM sleep. Steady NREM sleep has the lowest indices of variability of all sleep stages.

Minute ventilation decreases by 13% in steady stage II sleep and by 15% in steady slow wave sleep (Stage III and Stage IV sleep). Mean inspiratory flow is decreased but inspiratory duration and respiratory cycle duration are unchanged, resulting in an overall decreased tidal volume." **

http://en.wikipedia.org/wiki/Sleep_and_breathing

**unsourced

[greg-g]

I agree with the above posts.
As you haven't posted the flow limitation graph its a bit harder to comment, but I suspect you need a little more pressure.
You are getting a moderate number of obstructive apneas with no centrals, and a slight pressure increase should help.
I am not qualified to make this sujestion so you probably should discuss it with your sleep doctor. Personally I would see what happens with the pressure set to 8.

[karthikvprasad]

Thank you all for the detailed replies.
Here are the Flow Limitation & Snore Index graphs: https://picasaweb.google.com/lh/photo/O ... directlink
I too am very concerned about the fact that I had so many apnea episodes. With the machine, shouldn't the AHI index be close to zero?
Also, why is there so much of snoring? Should I try a full face mask instead of my nasal one?

Thanks!

[cflame1]

It's possible to have the AHI close to zero... but a lot of things play into that. Not the least of which is the pressure, the leak rate, possible sinus issues, food, drink, etc. This is why some folks will keep a sleep diary, to find out what was different night to night. Seeing as you only showed one night of detail, were the others the same, were they better or were they worse?

[SleepingUgly]

In theory an AHI < 5 is normal, but some people find they feel better the lower the number is. Others can't tell the difference in how they feel between 4.9 and .03.

[greg-g]

The snoring, flow limitation and events all go up at the same time, to me that indicates you need more pressure.
Personally I would increase the pressure slowly and see what happens.
If you had the S9 Autoset machine it would definatelly have increased the pressure at those times.

[ozij]

The snoring, flow limitation and events all go up at the same time, to me that indicates you need more pressure.
Personally I would increase the pressure slowly and see what happens.
If you had the S9 Autoset machine it would definatelly have increased the pressure at those times.

Good analysis and good advice by greg-g.
The coincidence of flow limitations and snores, and their clustering indicates that the present pressure isn't high enough for some parts of the night - and an AHI of 5.6 can - should be - improved. I wouldn't aim for 0 -- but I would try to find a pressure where I did not snore.

Before you raise the pressure, I suggest you try changing the EPR. It gives wonderful exhale pressure relief for some people, especially if their pressure is high - but may have an adverse impact for others. Unless there is a specifc health related reason for you to have an EPR of 3, I suggest you try EPR=2 and see what impact that has.

[avi123]

Your graphs look good to me. If you start playing with pressures you might end up like me which was USELESS.

Raising the pressure did nothing for me, dealing with the Obstructives, but created more Centrals and Hypops.

My PSG results from 8 months ago was "severe OSA", with AHI of 45 at pre CPAP.

PSG recommended a CPAP set at 6 to 7 cm which reduced the AHI to around 3.

But, I could not repeat the PSG results with such low pressure.

So I set the machine in CPAP mode at 10 to 11 cm with EPR at 2, all time.


My 3 months Stats are:

Statistics

4/17/2011 - 7/16/2011

For both S9 Autoset and S9 Elite:

Device Settings:

Pressure - cmH2O
Median: 11.0 95th Percentile: 11.0 Maximum: 11.2

Leak - L/min:
Median: 0.0 95th Percentile: 10.8 Maximum: 22.8

AHI & AI - Events/hr:
Apnea index: 8.9 AHI: 11.2 Obstructive: 5.0
Central: 3.4 Unknown: 0.0 Hypopnea index: 2.3

Usage:
Total hours used: 611:26 Average daily usage: 6:43

My present Epworth Sleepiness Score is around 6.

I might have underlying medical conditions?

You can try to raise the pressure as I did here, in the following graph (but gradually), to see if it would suppress your Obstructive apneas (it did not in my case):

[karthikvprasad]

Thank you so much for all your comments, folks! Much appreciated!!

[Lizistired]

I agree with ozij, except I would turn the EPR off and see if you need it. If you do you will know it right away and then start at 1 and work your way up if you need to. DMEs seem to set it at 3 to make it most comfortable, but they also set your Sleep quality to usage so you can't see what your AHI is.