CPAPtalk.com

To my uneducated way of thinking, if I had a ResScan chart that looked like that and I knew my leak rate was under control (preferably 0.0) so that I knew I could trust those numbers, then I would (1) set my machine to straight CPAP with NO EPR at 10 cm to get a baseline for at least four days, and then I would (2) see what 12 cm did for a few days after that and then (3) see what 8 cm did for a few days, all with NO EPR. That might give me some indication of what direction I would need to go in the future. I would also look at my sleep study info to see if my apneas were positional.

Dear SWS, Muse-Inc, and JNK,
SWS, I envy your freedom to head to warmer climes this time of year and hope you enjoy that opportunity. I am not saying that you should read those papers, but if you want a pdf version of them emailed to you, then I would -- perhaps after you return from your trip so as to not clog your email in-tray. Also thank you for raising the issue of the pressures. And finally about the dental appliance. I obtained from my sleep specialist last week a "letter of medical necessity" for an oral appliance (mandibular retraction device) for the reasons you suggested. My tentative plan is to give the CPAP or Autoset another month and then decide to go for the oral appliance. I've read the discussion at cpaptalk.com and gather that combining the CPAP and oral appliance might not be the best thing to do (are you suggesting otherwise?).

Muse-Inc, thank you for the reminder about xylitol. I have heard that that is a good way to reduce bacterial activity in the mouth. I was encouraged after radiation to get xylitol gum and chew it regularly. Unfortunately for me I am frugal and xylitol gum is neither covered by my insurance nor as cheaply and readily available as I would have liked. Reminded by your note and given my evolving perspective on values, I think I will buy some xylitol gum and give it a try. You asked about my Home Depot insulation. After reading about the value of insulation to reduce rain-out, I went to Home Depot and bought two different pipe insulators. Each only cost a few dollars for a 6-foot length. One is plastic (I guess polyethylene -- material somewhat like a disposable coffee cup), light, somewhat rigid, and has a slit that allows it to be easily put around a CPAP hose and easily removed. The other is thicker and more pliable (I guess neoprene). My mother also took some socks and put them together to make me a hose. I also use now the Zoo Med repti-cable sometimes on a hose with no insulation. However, beyond those approaches the best for me comes again from advice from others on cpaptalk.com and that is to sleep with my hose under the covers and against my body.

JNK, I like your experimental approach. I should try that -- no EPR, 4 days at 10, 4 days at 12, and 4 days at 8. What does confuse matters some are other parameters. You asked about position. My sleep studies did show a significant positional influence -- namely when I am on my side, I have fewer apneas. Unfortunately, both my shoulder spasms and my life-long history of having been a flat-on-my-back sleeper, make sleeping on my side challenging. I have done some as-of-yet inconclusive experimenting with sleeping at a 30 degree angle but on my back versus on my side. My point is that a number of other confounding variables are at work. I did try two nights ago after SWS's recommendation, to use CPAP at 10 and no EPR and I had a bad night. But again I can see the wisdom of an experiment as you suggested. Maybe I'll start at the low end -- with CPAP of 8 tonight and see where that takes me but be contemplating to try 4 nights of CPAP 8, then 4 nights of CPAP 10, and 4 nights of CPAP 12 -- in the spirit of what you suggested.
Thank you again,
Roy

rada wrote: I've read the discussion at cpaptalk.com and gather that combining the CPAP and oral appliance might not be the best thing to do (are you suggesting otherwise?).

Most patients do report a difficult time combining CPAP with a dental appliance. However, some patients here have successfully combined them. I think I'd be inclined to try the CPAP without the dental appliance first; then the dental appliance without the CPAP; finally a combination trial if necessary...

I'll certainly drop you a PM when I get back. Again, thanks for the very kind offer to read your papers.

.

secret agent girl wrote:

jnk wrote:To my uneducated way of thinking, if I had a ResScan chart that looked like that and I knew my leak rate was under control (preferably 0.0) so that I knew I could trust those numbers, then I would (1) set my machine to straight CPAP with NO EPR at 10 cm to get a baseline for at least four days, and then I would (2) see what 12 cm did for a few days after that and then (3) see what 8 cm did for a few days, all with NO EPR. That might give me some indication of what direction I would need to go in the future. I would also look at my sleep study info to see if my apneas were positional.

jnk, I'm wondering about the 'no EPR' suggestion with these trials--would you share your reasons? How much would it mess up the results if a person really needed some EPR, say the lowest setting, 1?

I think EPR is great. In fact, I use a bilevel. BUT, in order to zero out all factors but pressure for a baseline, I think it can be useful to try pressure without any expiratory relief, especially if there is a chance that centrals are a factor, in my opinion. EPR would keep getting suspended with some events on that machine anyway, and the constant change from EPR-on to EPR-off throughout the night would be something I would want to disable if I was simply trying to establish some baseline numbers and figure out which direction, up or down in pressure, I should be exploring. EPR could later be engaged for actual treatment once I knew what I needed to know.

BUT, first things first, which would mean getting leak low and constant, within reason, so that the data is trustworthy. After that, home-machine data can be used, in the light of the data from the lab/center sleep studies, to start methodically plotting where pressure should be, or what range of pressures. If the apneas are highly positional, though, variations in how much time is spent in different positions can skew the data beyond usefulness, so I would want to rig up something to stay in one position, within reason, so that I knew that wasn't the primary factor in the data.

My suggestion was based on the look of that ResScan chart in this one case. For the most part, I think EPR is a good thing for most people, and especially those starting out on PAP. But when it comes to troubleshooting, it is important to realize that ResMed EPR lowers expiratory pressure, much like EPAP on a bilevel, and that EPR is suspended when certain events are detected. No matter how nice those variables are in most situations, I would want to remove them if I was having trouble establishing whether my pressure, or range of pressures, should be increased or decreased.

But, hey, that's just me.

jeff

Dear JNK, SWS, and Secret Agent Girl,
JNK, I like your tag line "In theory, there is no difference between theory and practice; in practice, there is.", although I am unclear on its meaning. On the one hand it points to circularity; on the other hand, my current situation might illustrate it. I endorsed your proposed experiment and intended to do 4 days of 8, followed by 4 days 10, and finally 4 days of 12. Well, the theory was fine, but the practice was not. I went to bed with a nasal mask (activa), with pressure at continuous 8, and with EPR off at 12:30 a.m. Jan 19. I was doing well on the AHI till about 3:30 a.m. Between 3:00 and 3:20 I had 6 apneic incidents with an average duration of 31 seconds. The graph follows:

I was so uncomfortable that I could not rest. I changed the pressure to CPAP 10 and changed from a nasal activa mask to a full face mask mirage quattro. The pressure chart shows that 0 pressure gap at 3:20 a.m. The other few dips in the pressure chart are evidently due to leaks as one can tell by aligning the leak chart with the pressure chart. Here is the leak chart:

Unfortunately, the apneic incidents continued. From 3:30 till 3:45 a.m. I had 9 apneic events with an average duration of 18 seconds. At 4:40 a.m. I had a cluster of hyponeas, one apnea, and a major leak. I was having an unhappy night and awoke in the middle of a nightmare actually catching myself choking inside my full-fask mask -- namely gasping for air. That's the first time ever that I remember awaking while choking. All other times I have awoken and assumed from the ResScan data (or the doctor's sleep study data) that I had been choking. Anyhow, desperate to simply get some good sleep, I switched at 4:45 a.m. to what had been my routine which was an autoset at about 8.6 to 12.4 and a full EPR.
From 4:50 to 5:30 I had 12 apneas with an average duration of 11 seconds. At 6:20 a.m. my wife's alarm rang and she left my bed and I awoke. I was not feeling rested and not breathing comfortably. I took of the mask, turned off the machine, and went to sleep for another 1.5 hours with no respirator support. That rest began with numerous deep breaths that I evidently was craving to have.
So what's the lesson from that? Of the many possible interpretations, let me take for now the simple interpretation that maybe 8 and 10 pressures are not enough for me. Tonight I’ll try CPAP at 11 – a more gradual approach than jumping to 12.
SWS, your suggesting oral appliance and CPAP might be usefully combined for some people may stimulate me to try to get the oral appliance very soon.
Secret Agent Girl and JNK, I also had Secret Agent Girl's question about EPR. I appreciate JNK's response. I understand the theory of wanting to control the variables and have the experiment definitively test a hypothesis. By the way, JNK also emphasized keeping the position constant. I have struggled with this for years and have tried many things such as a vest with pockets on the back into which were embedded tennis balls, complex arrays of a dozen pillows, and sleeping on the edge of the bed. However, each time my subconscious mind desiring to get me on my back overcomes my efforts to stay on my side.
Thank you,
Roy

rada wrote:...xylitol...

This has been percolating in the back of my mind since I posted: xylitol is readily avialable in health food stores and not too expensive. If you do try the banana smoothie, how 'bout rinsing with a mild solution of xylitol dissolved in water? I have no idea what the proportion should be to cut down on bacteria (maybe the Spry folks have the data and would be willing to share). Spry (they make the most products with xylitol) might even make a toothpaste with it.

Thanks for answering the insulation question..I simply could not imagine what Home Depot sold that would work as insulators for our hoses . Gotta love the ingenuity we read here!

Dear Muse-Inc, SWS, JNK, and others,
Muse-Inc, thank you for the pointer about xylitol in whole food stores. I retract my earlier observation about cost of xylitol and will go to a Whole Food store in downtown Baltimore today.
SWS, JNK, and others, I have been remiss in the plan of 4 days of 10 cmH20, as I collapsed the first experiment into a single night and last night went instead for narrowing the range on my autoset. I realize part of the idea was to avoid autoset and try a constant pressure, but I like autoset and narrowed the band so much that it became close to cpap. Allow me please to share last night's results because they are remarkable as regards the 10-second apneas. First for the context: I put autoset min at 9.4 cmH20 and the max at 12 cmH20 (I am also using EPR). I was very vigilant about sleeping on my side (about 3 a.m. I awoke and consciously rested briefly on my back and then went again on my side). The data show a large number of 10-second apneas. Remarkably, the chart shows twenty 10-second apneas and only 5 other apneas for an average, apnea duration of 11.16 seconds. What does this mean?
Here's the 8-hour Events chart:

The statistics give an AHI of 21 and an AI of 5.4. The 95th percentile leak was 0.4 liters/second. My leak chart does not look particularly good to me with the 95% being at 0.4 liters/second. Here's the leak and pressure chart:

I have read some of Velbor's helpful, detailed description about leaks at cpaptalk. I also understand from reading this morning that leaks above 0.7 liters/sec make the pressurized breathing support unreliable. Might leaks cause the machine to think that an apnea or hyponea is occurring when it is not and/or might they lead the machine to adjust pressures? I searched on cpaptalk but had difficulty getting an answer to the causal relationship between leaks and events. I found an article at http://memo.cgu.edu.tw/cgmj/2906/290607.pdf entitled "Comparison Optimal Pressure between Automatic Titrating and Predicting Continuous Positive Airway Pressure" which included a comparison of the effect of leaks on autosetting respirators. The article noted a strong correlation between leaks and the autoset pressures. That makes sense to me but still leaves me wondering whether my AHI would be different were my leaks different.
Finally, I would like to ask about the hpyoneas. On the 8 hour chart, I seem to be in constant hyponea which would seem to be inconsistent with the measurement of hyponeas as a reduced airflow relative to the immediately preceding airflow. When I change the time scale from 8 hours to 30 minutes, the hyponeas are interestingly spaced. Might my recorded hyponeas be a reflection of something physiologically healthy, like a long expiration, or are they more likely signs of a pathology, like a spastic genioglossus muscle? Here's a snippet from Event chart for 30 minutes:

Looking at the data again and thinking about what people might recommend, I guess JNK would remind me that I did not finish the experiment and that I should try a fixed CPAP for some days with no EPR for the possibility the changing pressures are themselves the culprit. I suppose my reluctance to do that is that my personal feeling about my night's sleep is that I feel better after an autoset night than after a CPAP night, but I'll ponder the experimental possibilities, as well as be sensitive to any feedback. (By the way, after studying cpaptalk, I ordered this morning from OximetersOnline.com a CMS 50E oximeter at $119.99 so that I could better monitor my sleep apnea).
Thank you for your help,
Roy

I have no idea about what would make a chart look like that. I would assume it means AutoSet is having trouble with figuring out your breathing because of some unique things about you anatomically or medically. I am a relatively new patient who doesn't know much, though.

I only know that if it was me, I would choose to concentrate on getting my leak constant and low and rigging something up to be SURE I wasn't sneaking onto my back while asleep so I would then be in a position to titrate myself, instead of leaving it up to an auto machine with variable EPR that seems to be having a difficult time figuring out my breathing and getting my apnea index lower on its own.

Table of Contents
1 Motivation for Writing Now 1
2 Ten-second apneas 1
3 Oximeter 1
4 Mask Effect 2
5 Immediate Plan 2

1 Motivation for Writing Now
I am writing this to report to cpaptalk.com since my last post of Jan 20. JNK had feedback on Jan 20 (and Secret Agent Girl on another thread also on Jan 20), and I had not replied. I don't want people to think that I lost interest, as the opposite is true. I have been keeping extensive notes every day and studying the cpaptalk.com site. The host of variables (such as, mask, leaks, position, and my psyche) confounds knowing what is causing what. I give here simply an interim update with little substantially resolved.
2 Ten-second apneas
I have been using my new CMS50E oximeter everyday and that helps me to understand what is happening. The 10-second apneas hardly impact pO2 -- namely I can have 10-second apneas and see no reduced pO2. On the other hand, I have noticed that my hyponeas contribute significantly to a reduced pO2. That hyponeas reduce pO2 makes perfect sense, as the air flow is reduced; however, I had been focusing so hard on the apneas that I largely ignored the hyponeas -- I am changing my view to pay attention to both. When the 10-second apneas are clustered with other longer apneas or multiple hyponeas, then the pO2 drops significantly. I am still unclear on the significance of an isolated 10-second apnea, but my data of late has been so varied that I am not currently focused on the 10-second apnea issue.
3 Oximeter
The CMS50E software is very nice in many ways. I save each day the full oximetry strips and the summary report. I have also found it helpful to pull the data file that the CMS50E generates -- a ".csv" file and to generate some stats from that. Since noise arises and gives zeroes in the data when I remove the oximeter for some minutes or for other reasons, I need to remove the zeroes from the computation. My formula for getting my data last night when I had 33,583 seconds of data is this:


SP02
average =AVERAGE(IF($A$1:$A$33583=0,FALSE,$A$1:$A$33583))
stdev =STDEV(IF($A$1:$A$33583=0,FALSE,$A$1:$A$33583))
min =MIN(IF($A$1:$A$33583=0,FALSE,$A$1:$A$33583))
max =MAX(IF($A$1:$A$33583=0,FALSE,$A$1:$A$33583))

and for last night gives this result:
SP02
average 96.78
stdev 1.23
min 86.00
max 99.00

I would like some better software for both viewing the CMS50E data and generating snapshot statistical data. I could build something in Excel VBA and might do that. If someone else has generated such, then I'd appreciate being able to collaborate.
4 Mask Effect
Jan 29 and Jan 30 I used my full-face mask because I have been having a runny nose and feel that the full-face mask better allows me to breathe than nasal pillows. However, my Sp02 values were worse last night than when I used nasal pillows on Jan 24 and 25, and I am unclear why.
SpO2
nasal ; nasal ; full ; full
Jan24 ; Jan25 ; Jan29 ; Jan30
average 97.73 ; 97.58 ; 97.31 ; 96.78
standard deviation 0.7 ; 0.84 ; 1.0 ; 1.38
minimum 92 ; 92 ; 84 ; 86

Tonight I am going to try nasal pillows again. I wonder whether something about my being able to exhale a little from my mouth without confronting incoming air pressure with the nasal pillows might account for some difference in ultimate result (for instance, might that ability to exhale (without re-breathing my CO2 as much as when I exhale via mouth into the full-face mask) help me keep my internal CO2 monitor at some setting that reduces the likelihood that my brain puts me into a central apnea).
5 Immediate Plan
Tonight I am going to try nasal pillows. I will also spend some time today trying to setup a way to video (via Secret Agent Girls' suggestion) myself in sleep so that I can study how my position changes and relate that to apneas and pO2.

rada wrote: Currently I sometimes put Biotene mouth gel in my mouth before sleep in order to provide some lubrication in my mouth.

Here is something I learned about using Biotene gel that made a big difference for me - viewtopic.php?f=1&t=47608&p=430774&hili ... ne#p430774

Finally have my webcam setup. I tried a few days ago with Windows Movie Maker but could not get the screen to go into saver mode while Windows Movie Maker was working. Last night I downloaded yawcam from http://www.yawcam.com and am pleased with it based on one night's usage. I set it to store a low resolution image once every minute and time stamp the file name.
My ResScan report was better than usual for last night though I do not feel rested -- maybe because of not enough sleep and also because I awoke once in the middle of the night with a very dry mouth and needing to go to the urinal -- you know the script. Anyhow, I started trying to go to sleep at 00:30 a.m. and arose from bed at 6:30 a.m.. During that time ResScan only records one apneic event; however, the hyponea index is 4.2 per hour, and they are scattered roughly as follows (including also the apnea):
A. four between 1:30 and 1:45 a.m.
B. four between 2:30 and 2:40 a.m.
C. ten between 3:05 and 3:35 a.m.
D. two at 4:45 a.m. (and also 12 second apnea at this time).
As an experimentalist, I now hypothesize the following:
The apnea and hyponea events will correspond with a relative drop in pO2 and a tendency to be on my back (whereas when I am event-free, I am on my side).
Here is the O2 summary
• O2 between 96 and 99 from 00:30 to 3:30 a.m.
• O2 between 94 and 98 between 3:40 and 3:50
• O2 between 96 and 98 between 3:50 and 4:30
• O2 drop to 93 at 4:50 a.m. and to 95 at 5:15 a.m. but otherwise between 96 and 99 from 4:30 and 5:30
• O2 between 94 and 96 between 5:40 and 6:20 a.m.
The first two groups of four hyponeas did not reflect clearly in the O2 data, and the ten between 3:05 and 3:35 seemed to lead to going to the bathroom at 3:35 a.m. and then a substantial drop in 02 at 3:40 a.m. but that might be artifact from bathroom trip. The only definitive drop in O2 that maps clearly to a apnea-hyponea event is the 12 second apnea at 4:45 a.m. corresponding to a drop of O2 to 93.
So my refined hypothesis would be that I was on my back at 4:45 a.m.
The video shows:
• started to sleep on left side at 00:30 a.m. and stayed there till 2:18 a.m.
• on back from 2:18 till 3:38 but with frequent small motions of head
• at 3:38 arose and then resumed on left side sleeping till 5:12 but with frequent small motions of head from 4:37 till 5:05
• moved to back and then again to left side between 5:11 and 5:15.
• 5:40 removed mask and went to right side till arose at 6:24 a.m.
My hypotheses were not strongly supported. As regards the pO2, while the one apneic event corresponds with a drop in pO2, the couple dozen hyponeas did not clearly correspond with pO2 drops. As regards position, being on back did not seem to be the sine qua non of respiratory distress that I had hypothesized. However, another observation comes from the data -- an unexpected one given that I am a nay-sayer about CPAP and have been preparing to get my oral appliance and ditch CPAP. Namely, look at the drop in O2 from 5:40 to 6:20 and the video results -- I removed my mask for that time. Let me check the average pO2 numbers more precisely with the new hypothesis being that the respirator helps.
I retrieved the csv file generated by the oximeter and using my own Excel formulas computed the following:
• from 00:35 till 5:40 a.m. my Sp02 average was 97.48 with stdev 0.66 and min of 94.
• from 5:40 till 6:20 a.m. my SpO2 average was 96.30 with stdev 0.80 and min of 94.
The new hypothesis is supported. The respirator helps. Admittedly, one case does not a significant result constitute. Other factors could be at work here, such as my stage of sleep, the activity of my wife at 6 a.m., and so on. However (rest assured -- pun intended), I will pursue this experiment in subsequent nights.
Any feedback welcome.
We intrepid sleep apnea patients have to become our own best subject.
Roy

while the one apneic event corresponds with a drop in pO2, the couple dozen hyponeas did not clearly correspond with pO2 drops

That is the reason the people who created the Resmed algorith did not have it respond to apnea. Their rationale was that hypopneas are often the result of sighs, turning in bed, and not necessarily obstructive apenas. Looks like that may be your case.

O.

Two nights ago, I was delighted to find that sleeping on my back seemed okay and that the respirator overcame the position. Today I re-assess.
By the way, the record will also show that in honor of the worst blizzard in a long time in my Baltimore, the electricity stopped in the middle of the night. Not good for continuity of service from respirator and webcam. Time to shop for an uninterruptible power supply. Looking now at possibilities, I see my respirator is 2.5 amps. Does that make it 2.5 amps *110 volts = 275 watts? That would already put me over the capacity of the cheapo UPS. Does this look good: Black Vision Budget 650 Uninterruptible Power Supply, 650VA / 390W, w/ Blue LCD Display, Model: Budget-Blue-650VA for $67 from directron.com?
Back to the main story. Had this ResScan result last night:

AHI of 16.3. Not looking pretty between between 4:50 and 6:10 a.m.; that interval shows 17 apneic events (but notice largest duration of 14 sec) and 55 hyponeic events (including the 17 apneas). From the night before last, I thought sleeping on my back was protected by respirator, but now I am going to guess that
• I was on my back during the many events, and
• my pO2 suffered while I was on my back.
The conclusion would then be that I should avoid sleeping on my back. Let's see what the data show.
SpO2 shows dip to
• 92% at 00:10 a.m.
• 93% at 2:10 a.m.
• 93% from 3:15 to 3:21 a.m.
• disconnected from 3:45 to 4:40 a.m.
• 93% from 6:03 to 6:12 a.m.
From 4:50 to 6:03 a.m. the SpO2 was fine -- bouncing around 97%. Surprise! Surprise! Surprise! Many apneas and hyponeas but good SpO2. This returns me to the original question of this discussion thread: What is the significance of a large number of low duration apneas? In this case, also compounded with a large number of hyponeas.
To finish testing the hypothesis, I need to now check the video. I used a red light last night and the resolution is poor. Guessing at what the photos show, I'll say:
• on left side from midnite till 3:10 a.m.
• then switched to right side till blackout at 3:54 a.m.
• from 4:59 a.m. till 5:57 a.m. I was on my back (with just one pillow)
• between 5:57 and 6:30 tossing and turning. Then disconnected everything but stayed in bed snoozing till 8 a.m.
The Resmed registered hyponeas and apneas were not significant as far as either SpO2 or sleep continuity were concerned. Amazing! I could sleep on my back and breathe well with the respirator despite what the Resmed algorithm detects.
Where do I go next? Aside from the minor technical stuff of getting a surge protector, dealing with the poor lighting, and such, what do I do strategically in terms of sleeping? I suppose tonight I won't make any concerted effort to stay on my side (also, instead of using the dozen pillows that I have been using often in the past months to try to elevate my head and support staying on my side, I'll use just one pillow).
Roy

I threatened to write some code to take CMS50E oximeter and get average and stdev for time period and I did now. This is uncommented and depends on treating the spreadsheet by calling it data and naming some ranges in it. If someone's interested, then we could work together to make it useable to others, but for my purposes for now I'm done. Here's the top of the spreadsheet which probably won't format properly when I paste it into cpaptalk.com but I'm not going to mess with making an image file now. After that is the bulk of the code.

SPO2 PULSE sleep hour, min, sec Ave Stdev Min Max
0 0 1 57 0 97.31 0.81 91 99
0 0 start
0 0 4 4 0
0 0 stop
0 0 8 33 0


Sub Start()
Dim i As Integer, s As Integer, sa As Integer, sb As Integer
Dim nSecs As Integer
Sheets("data").Activate
nSecs = LengthColumn("A2", "data")
s = Range("hr") * 60 * 60 + Range("min") * 60 + Range("sec")
sa = (Range("hra") * 60 * 60 + Range("mina") * 60 + Range("seca")) - s + 2
sb = (Range("hrb") * 60 * 60 + Range("minb") * 60 + Range("secb")) - s + 2

Range("Ave").FormulaArray = "=Average(IF(A" & sa & _
":A" & sb & "=0,FALSE, A" & sa & ":A" & sb & "))"

Range("StDev").FormulaArray = "=stdev(IF(A" & sa & _
":A" & sb & "=0,FALSE, A" & sa & ":A" & sb & "))"

Range("m").FormulaArray = "=min(IF(A" & sa & _
":A" & sb & "=0,FALSE, A" & sa & ":A" & sb & "))"

Range("max").FormulaArray = "=max(IF(A" & sa & _
":A" & sb & "=0,FALSE, A" & sa & ":A" & sb & "))"

Range("Ave").NumberFormat = "##0.00"
Range("Stdev").NumberFormat = "##0.00"
End Sub