What can cause a PRS1 Auto to malfunction without warning?

Greetings all! I am awake in the middle of the night afraid to go back to sleep *l* This forum seems to carry a lot of knowledge and seems to stay active all hours so I am hoping to get lucky.

This last weekend I finally made the apnea connection and gathered some equipment off craigslist to try to do battle. (Rx not an option unfortunately).

Sunday night I had enough pieces between them to assemble a functional system but the mask I had to use was a Quattro that was two sizes too small. After stretching the cushion to clamp against the top of my lower lip I was able to get it to seal enough to function with the machine in Auto range 4-20 but was woke up a few times by air leaks and a couple times trying to gasp through lips that were sealed shut by the mask. However, I woke up feeling so much better than I can remember that I knew I was on the right track. My AHI for the evening was 5.5 with the pressure ranging from 6-10.

Yesterday I could not bring myself to use the undersized mask again so I decided to fashion a repair to replace the missing piece on the other mask I had acquired. I took a short piece of tubing to replace the gray "swivel" on the properly sized Simplus and figured it should be fine because the inside diameter of the pieces was no smaller than the i.d. of the Simplus elbow it attached to.

I slept horribly and kept waking up to regain my breath (which is unusual because I was never aware of my awakenings the previous 30 yr or however long it has been). After four hours I could not sleep any more suffering the familiar headache and brain fog. Wondering what the problem is I checked the data card to find the AHI averaged 39.6 and the pressure was mostly flat-lined at 4 with one short visit to 6 and an occasional short visit to 5.

I have no idea why the machine would detect the data but not respond. Does anyone know enough about how these machines work to make an educated guess whether the makeshift repairs could have caused this or whether something is toasted? I am thinking maybe I can put it in CPAP mode set on 11 based on last night readings to make it through the rest of the night but I would like to get a handle on this ASAP.

What do the leak numbers look like?

kaiasgram wrote:What do the leak numbers look like?

It looks like leak numbers were hovering around 48-65. Sunday night with the undersized mask they spent more time 60-80.

I would need to see the software reports from both nights to compare them.
Also need to know exactly which machine.

If it's the machine itself (which I tend to doubt anyway ) if there is a problem with the blower sensor I doubt you can fix it.
I have seen what you describe happen on Respironics machines are clueless because of a really big leak.

So we don't know where you got those leak numbers?
Which machine they came from and big leak can vary with brands.
Are they total leak numbers or excess leak numbers from the graphs?

Pugsy wrote:I would need to see the software reports from both nights to compare them.
Also need to know exactly which machine.

I am not sure what additional details you need? The link in my sig leads to a machine that seems the same but with three model numbers listed. The "REF" number on my machine is 550P if that helps.

Pugsy wrote:If it's the machine itself (which I tend to doubt anyway ) if there is a problem with the blower sensor I doubt you can fix it.
I have seen what you describe happen on Respironics machines are clueless because of a really big leak.

That is actually very encouraging if you have seen it before. I ended up switching to CPAP mode constant pressure to get a little sleep after which the events then looked similar to Sunday night and the AHI average dropped from 40 to 18.

Pugsy wrote:So we don't know where you got those leak numbers?
Which machine they came from and big leak can vary with brands.
Are they total leak numbers or excess leak numbers from the graphs?

The leak numbers are from total leak range shown on the graph. SleepyHead is very unstable on my machine (W7) and I am trying to find resolution but it makes difficult to capture a decent screen shot. I can tell you that when I set the constant pressure to 10 I could then feel leaking and trying to adjust the mask it seems the Simplus might be too big for me after all but I was exhausted and putting on the undersized mask is a last resort. The report for the second half of the night showed excess leak flags at 10cmh2o almost the entire duration but I was able to breathe at least.

Thank you for your help! I can try to get a SH report uploaded if you think it may still help. I am not sure why it leaked so bad at 10cmh2o but seemed to hold like a rock when I did the "fit test" which I believe uses max pressure. For now I am inclined to blame the issue on the leaks so for now my goal is to get this boat ashore with an empty bilge and work from there.

Cheers,
Paul

I am not familiar with the Simplus mask, but on the Wisp that I use the required exhaust port is in the elbow. If you replaced the elbow with straight tubing your exhale breath has nowhere to go. That would likely cause the leaks and could render all the data invalid.
This is all conjecture until we know exactly which machine you have.

I second what Pugsy says about leaks, if the leaks are too high, the machine won't ever increase pressure.

and those leaks are too high.

if it's at 4cm, then your leaks should be closer to 20.

amazon or ebay yourself a mask that's the right size

also, increase the minimum pressure to 6 or 7

Bwexler's comment is very important. If your mask repair replaced the vent with a piece of hose, then you could be in deep trouble if you keep using it. The vent is there to get the carbon dioxide out.

mralaska wrote: I slept horribly and kept waking up to regain my breath (which is unusual because I was never aware of my awakenings the previous 30 yr or however long it has been). After four hours I could not sleep any more suffering the familiar headache and brain fog. Wondering what the problem is I checked the data card to find the AHI averaged 39.6 and the pressure was mostly flat-lined at 4 with one short visit to 6 and an occasional short visit to 5.

Without knowing more about what kind of events were being scored and how far apart the events were, it's impossible to answer your question.

If a large number of the events were scored as CAs, that would explain why the machine did not increase the pressure. (And if you "kept waking up", then there's a real chance that many of the "events" were sleep transitional CAs, which ordinarily would not be scored on a sleep test.)

If there is at least a minute or two between most of the OA and H events, that would explain why the machine did not increase the pressure.

If the total leaks were sufficiently high, that would explain why the machine did not increase the pressure.

And it's not clear which SleepyHead leak numbers you're talking about when you write:

mralaska wrote:It looks like leak numbers were hovering around 48-65. Sunday night with the undersized mask they spent more time 60-80.

If those are Total Leak Rate numbers, then leaks are probably not the problem.

If those are Leak Rate numbers, then they are SH's approximation of the excess leakage, and they're high enough where they may be problematic. We'd need to see the actual leak graph to be sure.

Were any of the leaks flagged as official Large Leaks?

The mask is extremely important! Modifying masks is probably not a good idea. There is a lot of variation as to which kind of mask works best for each person. Check the results of the poll I posted here: viewtopic.php?f=1&t=104522&p=985849&hilit=+poll#p985849
There seem to be lots of masks available on craigslist so you may want to try some different types. The breeze nasal pillows work wonderfully for me.

FWIW....those reports I talked about where the auto machine was behaving like cpap mode...I initially missed the leak being the problem because the total leak was off the chart more or less and I was eyeballing the bottom (excess leak) line and thinking it was the top leak line.

With people new to the software reports...what they say they are seeing...I don't doubt it but we need to see to confirm that we are all on the same page with what we are seeing and thinking.
I have had people tell me that the numbers off the excess leak line graph were the total leak (top line) because that's what they thought. They didn't understand what the difference was.
It's just easier to ask for a screenshot so we can all see what the OP is seeing.

Not sure why SleepyHead is being flaky for you but if you have a Windows computer and want to try Encore send me a private message. Encore is strictly Windows though.

bwexler wrote:I am not familiar with the Simplus mask, but on the Wisp that I use the required exhaust port is in the elbow. If you replaced the elbow with straight tubing your exhale breath has nowhere to go. That would likely cause the leaks and could render all the data invalid.
This is all conjecture until we know exactly which machine you have.

Does my profile need to be approved before people can see my equipment used? I made sure it was all entered before I posted and I can see everyone else's. At any rate, it is a Philips Respironics System One Auto 50 series. The elbow is still in place. The missing part is a swivel that attaches. The only breathing I am missing is what would have blown out from the swivel but the Simplus is a higher leak mask than normal anyway so I was not worried about it.

palerider wrote:I second what Pugsy says about leaks, if the leaks are too high, the machine won't ever increase pressure.

and those leaks are too high.

if it's at 4cm, then your leaks should be closer to 20.

amazon or ebay yourself a mask that's the right size

also, increase the minimum pressure to 6 or 7

The PRS1 reports the numbers in a way that makes it easier to track total leaks. The Simplus is probably in the mid 30s from what I have read so I would like to get the leak under 50 (in my numbers).

I am hitting a few local options to see if I can get a better mask today, and also scouring the 'net to find something to order. It might be cheaper to order the parts for the Simplus, which can accommodate any size cushion on the standard frame.

Thanks for seconding Pugsy. It was disheartening to consider my machine might be going bad and I am starting to feel better. When I get the mask situation under control I will set the minimum to 6 or 7 as you suggest to go back to "Auto" mode. The first night it stayed right at 6 between events.

Nick Danger wrote:Bwexler's comment is very important. If your mask repair replaced the vent with a piece of hose, then you could be in deep trouble if you keep using it. The vent is there to get the carbon dioxide out.

Nothing significant was blocked. I will post a picture below of my modifications. The eye glasses were purchased at a discount store for $1 then specially modified to wear them with a FFM. The chin strap started out life as a top strap for a cheap LED headlamp but it makes a better chin strap. The tubing fit snug on the hose with the help of half a hose barb and some electrical tape to seal the deal. The I.D. of the hose barb is slightly larger than the i.d. of the elbow entrance:

Your machine choice in your profile points to the 50 series Auto CPAP model 550/551 and I see it just fine so everything appears to be correct.

If you could get a screen shot of the detailed report it would be really helpful.
Only thing we need to see is the stuff on the left side...AHI and statistics (turn off the pie chart and hide the calendar) and on the right side these graphs
Events
Pressure
Flow rate
Leaks

don't need any of the other graphs.
Examples of how it looks and explanation of how to get it done can be found here
viewtopic/t103468/Need-help-with-screen-shots.html

robysue wrote:

mralaska wrote: I slept horribly and kept waking up to regain my breath (which is unusual because I was never aware of my awakenings the previous 30 yr or however long it has been). After four hours I could not sleep any more suffering the familiar headache and brain fog. Wondering what the problem is I checked the data card to find the AHI averaged 39.6 and the pressure was mostly flat-lined at 4 with one short visit to 6 and an occasional short visit to 5.

Without knowing more about what kind of events were being scored and how far apart the events were, it's impossible to answer your question.

If a large number of the events were scored as CAs, that would explain why the machine did not increase the pressure. (And if you "kept waking up", then there's a real chance that many of the "events" were sleep transitional CAs, which ordinarily would not be scored on a sleep test.)

If there is at least a minute or two between most of the OA and H events, that would explain why the machine did not increase the pressure.

If the total leaks were sufficiently high, that would explain why the machine did not increase the pressure.

And it's not clear which SleepyHead leak numbers you're talking about when you write:

mralaska wrote:It looks like leak numbers were hovering around 48-65. Sunday night with the undersized mask they spent more time 60-80.

If those are Total Leak Rate numbers, then leaks are probably not the problem.

If those are Leak Rate numbers, then they are SH's approximation of the excess leakage, and they're high enough where they may be problematic. We'd need to see the actual leak graph to be sure.

Were any of the leaks flagged as official Large Leaks?

The events were pretty much spread across the board and all of them were Hypopnia except for one apnea event, perhaps because I never made it to deep sleep. I would have to get SH to settle down long enough to see how many were separated by a minute but some of them were clustered tighter than a minute so the machine should have responded. The leak numbers are total leak which seems to be what the PRS1 likes to report except for the mirror graph on the bottom of the leak screen. I think only a few ere flagged as large leaks but the pressure was pretty low.