Newbee with AVAPS Questions

[WEK]

I'm new to this forum and to sleep apnea therapy, so please bear with me as i struggle to figure this all out.

I had my sleep study done twice, once with CPAP and BiPap, the second using AVAPS. The doctor's report indicated an "Epworth sleepiness score of 14/24, with BMI of 48.2. Study revealed severe degree of sleep-disordered breathing during diagnostic portion of the study, with AHI of 101 per hour. He desatted to as low as 65%. End-tidal CO2 during diagnostic portion maintained between low 30 and high 30s." He recommended AVAPS with max IPAP pressure of 30, min IPAP pressure of 21, EPAP of 17 and tidal volume of 700mL, with rise time of 3 and ramp time of 0.

I have my machine now but have a few concerns. I hope someone can help.

CONCERN #1
When I first turn things on, put on the mack and settle in for the night, I can feel a constant pressure in the mask with additional pressure when I inhale. The inhale pressure pulses seem a little fast, but I'm getting used to it. As the night progresses, the pressures seem to reduce unit they feel almost non-extent. That lack of pressure usually wakes me up and occurs about two hours after going to bed. I look at the display on my machine and it indicates that the pressure is 17 or a bit higher. At this point, I take off the mask, shut down the machine and go back to sleep for the rest of the night. Whats with this and is it normal?

CONCERN #2
I'm a side sleeper. Always have been and probably always will be. I do not have a big problem with mask leaks. I just move my head a bit and the leak is gone. The problem is that I wake up around 5am with SEVER pain between my should-blades. To the point that it affects my breathing. I must get up and move around for about an hour for the pain to dissipate. So much for a really good nights sleep. Does anyone know what is causing this and how to fix it?

CONCERN #3
I would like to be able to tell how well (or not) the treatments are working. I have checked on software to be able to download the data from the SD card, but none seem to work. I have tried EncoreView 2.0, and SleepyHead 0.8.6. Neither will work with my SD card. Are there any other programs that I can get?

That about does it for now. Any help would be greatly appreciated.

[Pugsy]

Welcome to the forum
For specific comments I will let the other ASV users chime in.
This one I will address. It is common to feel like the pressures are non existent later on during the night. What starts off feeling like a hurricane will feel like a gentle breeze once the body gets use to it.
You shouldn't be removing the mask and turning off the machine though. Bad habit to start.

The inhale pressure pulses seem a little fast, but I'm getting used to it. As the night progresses, the pressures seem to reduce unit they feel almost non-extent. That lack of pressure usually wakes me up and occurs about two hours after going to bed. I look at the display on my machine and it indicates that the pressure is 17 or a bit higher. At this point, I take off the mask, shut down the machine and go back to sleep for the rest of the night. Whats with this and is it normal?

For your software question. Encore Viewer won't work with these new machines like you have. I will send you a private message in just a few minutes about Encore Pro 2.5.

SleepyHead should work. Are you having trouble downloading? Can't find the card?
The folder that is needed to be selected is actually the drive that the SD card is in.
See my example here.

If you have P Series folder in the select folder line, you have gone one step too far.

[jamiswolf]

WEK,
Welcome. There are plenty of very knowledgeable people to help you.

You say you were prescribed an avaps machine but your signature lists an asv auto servo ventilator. They are both high end machines and I'm not at all certain that avaps isn't incorporated into the asv machines. All rather complicated at that level of machine function. Double check to be sure that you have the right machine. It is not at all implausable that the DME gave you the wrong machine.

But with such bad desats and high frequency of apnea events...you need aggressive treatment.

Mask leaks at those pressures are difficult. But luckily there are plenty of guys and gals who battle that daily. Finding the one that fits you the best and then perhaps adding in a mask gasket are the usual approach...plus leaning how to adjust strap tightness for your face and pressure.
Good luck and hang in there. Persistence will pay off,
Jamis

Edit: You said you were a side sleeper? Good for you...you're better off. Many people get special pillows...specialized cpap pillows or buckwheat pillows that support your head yet allow your face and mask to be free and unencumbered. Research that a bit.

[WEK]

I was able to get Encore Pro and it is working fine. That takes care of Concern #3.

It appears that Concern #1 is normal. I'll just have to get used to it I guess. It just feels a little weird at 2am. All of the graphs have fairly flat lines, so it appears to be working. My AHI last night was 5.4 and over the past 10 days was 4.7 so I guess that is in the acceptable range.

Speaking of acceptable ranges, does anyone know what they are? It would be nice to have a target to shoot for. Here are the averages I have for the past 10 day period:
Pressure (IPAP): 24.2 (that looks right since my machine is set to 25)
Pressure (EPAP): 16.9 (Again, that looks right since my machine is set to 17)
Breaths Per Minute: 16.6 bpm
Tidal Volume: 651.1 mL
Patient Triggered Breaths: 100.0% (That must be perfect?)
Peak Flow: 42.0 lpm
Leak: 55.1
Minute Vent: 10.2
AHI: 4.7

Can someone explain what these SHOULD be?

I have the clinical notes from my doctor and it specifically states AVAPS. That goes to show you that I really know nothing about this stuff. I thought that AVAPS and ASV were the same. I'll check with my doctor when I see him on the 11th. I do have the machine listed in my profile.

Thanks everyone for the help so far.

[Pugsy]

Patient Triggered Breaths: 100.0% (That must be perfect?)

Doesn't get any better that is for sure. Patient Triggered Breaths are breaths that you initiate. So the machine doesn't have to breath for you. The more the better.

AHI....we like to see less than 5 but it will bounce around from time to time when you use this special machine.
Especially since starting out.

In the software there is a Glossary in the Help section that will explain the terms.
As far as acceptable ranges...Some will just be what is your normal.
I will let the other ASV users explain acceptable ranges as they know a whole lot more about those than I do.

One question though..... Leak 55 L/min...how do you have Encore Pro software set up to report leak?
The default is unintentional leak (mask intentional leak/vent rate is subtracted prior to reporting) and if this is unintentional leak...too much leak. Now if this is Total leak (vent rate plus excess or unintentional leak) then 55 L/min will be fine.
SleepyHead also reports Total Leak. So it makes a difference how the report shows it.

[WEK]

One question though..... Leak 55 L/min...how do you have Encore Pro software set up to report leak?

Encore Pro is reporting "Total Leak".

[Pugsy]

Encore Pro is reporting "Total Leak".

That is the overall average for the night and your leak rate is just fine. I don't know off hand what the vent rate for your mask is but at your pressures it is going to be sizable. Just look at the leak line itself to get an idea how it is going. Mostly straight or sort of straight is good. Stay away from the 90 L/min line and you will be fine. It's acceptable to have a few spikes upwards from time to time. We just don't want to spend a lot of time near the Large Leak line which is somewhere near that 90L/min line.
We aren't ever told exactly what constitutes Large leak. Just avoid large leak. I have seen 85 L/min flagged as Large leak. 80 line doesn't seem to flag it. Even a short term large leak I don't get in a panic over. They will happen every now and then. I once woke up with the nasal pillow blowing in my ear.. I had large leak then.

[deltadave]

I have the clinical notes from my doctor and it specifically states AVAPS.

AVAPS is used to reduce abnormally high pCO2 levels in respiratory failure. Since

End-tidal CO2 during diagnostic portion maintained between low 30 and high 30s.

it would seem that the choice of AVAPS is inappropriate.

[deltadave]

We aren't ever told exactly what constitutes Large leak.

The implication has been that Large Leak is >2x Expected Leak.

[deltadave]

Omigod, I have just been made aware of a HORRIBLE mistake I have made!

After assembling all my magnets in order to attract 2005 YU55 and trigger an ELE, as it turns out, the thing is made up largely of carbon!

So even if it does hit, it would seem that the only thing that would happen is that it would light up like some giant Kingsford Briquette and just be this tiny gray ash by the time it reached the planet surface.

Is that a drag of the nth degree or what?

I'm sooooo depressed.

Oh well, BLNT.

[Madalot]

Welcome to the forum.

I am the other AVAPS user (or at least the only other one I am aware of -- or at least that posts much).

I don't know for certain, but I also question whether ASV machines have AVAPS, but cannot say for certain one way or the other. I know there are AVAPS machines (Respironics) and then what I'm using, but I've never heard of an ASV using AVAPS.

There are a lot of really smart and helpful people here. They will do what they can to help you.

Anyway -- just wanted to welcome you to the forum.

[jamiswolf]

WEK,
From where you started from to where you are now...fantastic. So I wouldn't even mention the avap issue to them. Keep the machine you have. Or that's how I'd handle it. And as DeltaDave said, well no sense in paraphrasing.

DeltaDave wrote: it would seem that the choice of AVAPS is inappropriate

ASVs measure tidal volume and minute ventilation and can correct for weakness in those areas. Anyway, very good job..
amis

[deltadave]

We aren't ever told exactly what constitutes Large leak.

The implication has been that Large Leak is >2x Expected Leak.

This was considered upon review of the Leak Compensation presentation on the Respironics website:



That said, the corresponding leak graph certainly doesn't seem to be...

corresponding.

Perhaps additional criteria need to be met.

In Patent US5803065, there is discussion re: breath identification, including:

Additional improvements in leak compensation techniques are also contemplated by this invention. As noted in the above description concerning leak compensation, the algorithm described there relies on two requirements as follows: (1) the patient's inhaled and exhaled volumes over time are the same, (and indeed if the patient's rest volume just prior to the beginning of inspiration is the same from breath to breath, the inhaled and exhaled volumes for each individual breath will also be the same); (2) when the patient is inhaling, total flow is greater than leak flow and when the patient is exhaling total flow is less than leak flow.

Consequently, it may be that Large Leak (and this may be different from "Big Leak" described in the algorithm patents) is noted when inspiration (and therefore a breath) becomes unidentifiable (not to confused with "reduced" or "absent", and therefore hypopnea or apnea)(this could be overcome by insuring that Large Leak is a relatively long-term trend).

[Pugsy]

That said, the corresponding leak graph certainly doesn't seem to be...
corresponding.
Perhaps additional criteria need to be met.

I have scoured Respironics looking for anything that points to that additional criteria. I gave up. So all I have to go on is what I have seen on my reports. I rarely ever get a large leak flag but when I have it has been somewhere around 85L/mim to 90L/min Total Leak reporting. I use APAP so sometimes I have a wide range of pressure needs. That will of course affect the vent rate. Most of the time my overall pressure needs are around 12 (overall average). Using nasal pillow mask at these pressures you original comment about twice expected leak is pretty close. I have never used a full face mask or use high pressures consistently to see where large leak gets flagged. I do have a friend that uses 16.5 cpap pressure and a Quattro FX mask. It is hard to see exactly when she gets a large leak flag but 80 L/min won't flag it. Again seems to be 90 L/min and above.

While I would like a more definitive explanation of where and how large leak gets flagged, I have accepted that I can't find it and usually just tell people to look at the leak line itself. If it is relatively stable with only some minor fluctuations and rarely gets above 80 L/min for a short period of time then the leak is probably not great enough to severely impact therapy or data scoring. Not a perfect explanation I know but the best I can come up with.

[deltadave]

I do have a friend that uses 16.5 cpap pressure and a Quattro FX mask. It is hard to see exactly when she gets a large leak flag but 80 L/min won't flag it. Again seems to be 90 L/min and above...

Interestingly, Quattro FX Leak Rate at 16 cmH2O is 48 LPM (+/- 6 LPM).

A coincidence?

Or are there mysterious forces underfoot?