Varying AHI Readings on BiPap Auto SV Advanced

[-SWS]

Sleep disturbance masquerading as SDB.

My thought is that the respiratory events might be circadian in nature (hence, need about a month of detailed reports)(BTW, can you upload the first 3 pages of the detailed report?).

Repeated wakefulness during sleep can theoretically contribute to unstable central breathing/ventilation. You're wondering if JIMCHI might experience circadian cycles of nighttime wakefulness (impaired sleep drive)? Theoretically those could manifest as cyclic HI oscillations over many days as circadian sleep-drive waxes and wanes...

Here's my own relevant sleep/wake/sleep example resulting in frank central apneas: viewtopic/p563159/Collection-of-Oddball ... ml#p552606

I'm going to give this a try and will report results. ...post the results every day or just fill in the whole grid afterwards and then report ?

JIMCHI, post the results whenever you'd like.

Also had an issue when exhaling that it felt like there was little resistance- annoying and kept me from getting to sleep right away.

Do you have any thoughts about that problem I reported from last night-- that when I exhaled it seemed like there was a little resistance for maybe a second or two and then it just went to a full uninhibited exhale-- disturbing when you are trying to get to sleep and maybe, subconsciously, when you are sleeping. What variable affected that?

BiFlex strives to minimize the "feel" of exhale resistance. And when EPAP is low, the "feel" of exhale resistance is going to seem very low. If setting EPAP min too low bothers you, then I'd suggest skipping all EPAP min =4 trials. That would leave a 2 x 3 exploratory grid instead. If residual HI is still high after experimenting with that remaining 2 x 3 grid, you could always add another exploratory column for EPAP min = 10 (at those same three PS min values)---and pending doctor approval.

Here's a link to an album with the 4 pages of the Encore Reports plus last night's data.

It's very difficult to see any details on those reports. But I can see residual HI is still up there. Hoping sleep is okay.

For daytime functioning, all the EPAP 4.0s will be 14, the 6.0s will be 11, and the 8.0s will be normal (<10).

http://www.stanford.edu/~dement/epworth.html
JIMCHI, deltadave predicts that your experimental changes in daytime functioning (Epworth) will correlate to your changes in EPAP min. Lacking significant AHI variation, that prediction offers yet another implied assumption that your lower EPAP pressures can leave too many outstanding RERAs preventing restorative sleep:
http://www.google.com/search?q=rera+aro ... 1fdd569703

[Pap Goat]

Sense some is sharing, my AHI Friday with 6 hours sleep was 3, last night with the full 8, 5.

[-SWS]

Sense some is sharing, my AHI Friday with 6 hours sleep was 3, last night with the full 8, 5.

I think going from an untreated AHI of 60 (severe apnea) to your AHI of 3 Friday and then 5 in last night's graph is a nice improvement. However, immediately above Encore erroneously reported your central AI as 1.0----per a well-known Encore reporting math bug. One central apnea in more than 8 hours of sleep should not result in an hourly CA index of 1.0. Then that erroneous 1.0 CA score, in turn, was added to your HI of 4.0 for an incorrect total AHI of 5.0. I think we can also question that nice, round reported HI score of 4.0 as well. Lesson learned: don't trust Encore math.

Be sure to ask about bringing your PAP machine for use immediately after surgery if the staff hasn't already discussed that important detail with you. Good luck with tomorrow's knee-replacement surgery!

[Pap Goat]

Thursday was more like just over 5 hours sleep my mistake.

Encore math seemed a bit funny to me too. As long as I don't start seeing over 10, either way, good or bad math I'm going to be happy!

I'm taking my ASV machine for sure. I don't like how it feels to sleep with out it! My M Auto C-Pap with C-Flex was my first thought for taking with me but it never took care of my CSA. And be my luck I'd have a good one and wake up dead LOL.

I paid 2 grand for my ASV and didn't want the risk of it getting broke. When going on over night stays with my wife beside me she can wake me when she hears my M take off in the higher CFM numbers. But she won't be beside me so the ASV is going. Not only that the Surgeon knows I'm on an ASV, if he sees the M he may freak and tell my wife go after the ASV LOL.

Oh, yes all of my providers mentioned take it. MY DME, my family doc when I had my physical and my Surgeon. Seems no one wants me to croke on them ha ha!

Tomorrow I'll be gone for 5 or 6 days, I've enjoyed reading the CPAP community postings, thank you!

[JIMCHI]

sws- I have completed 5 nights using the grid. With an EPAP Min of 4 and PS Min of 5, I got AHI's of 9, 10, and 9 and % Triggered of 93, 97, and 93. As soon as I changed to the next setting of EPAP Min of 4 and PS Min of 6, my % Triggered changed dramatically. Only 2 nights so far but AHI was 10 and 9, but % Triggered was 86 and 81. I don't think those are good %. I got used to the lack of resistance on exhale and Flex is set at 0. Here's my chart from last night:

[-SWS]

...that grid attempts to "pattern flush" interplay among these dynamics: 1) central vs obstructive, 2) iatrogenic vs primary, 3) manual vs algorithmic treatment control.

With an EPAP Min of 4 and PS Min of 5, I got... % Triggered of 93, 97, and 93. As soon as I changed to...EAP Min of 4 and PS Min of 6, my % Triggered ...was 86 and 81.

I think we've isolated a salient dynamic in YOUR interplay between machine and respiratory drive: increasing PS Min from 5 to 6---while holding all other machine settings constant---just introduced an iatrogenic effect. Your respiratory drive needed significantly more machine backup by allowing PS Min to algorithmically drop no lower than a 6cm difference. Restating, your respiratory drive behaved better with the lower PS Min of 5 setting.

That isolated dynamic, in turn, suggests a strategy/ratio favoring as-needed or algorithmic PS treatment control---over higher manual PS treatment control---may turn out to be best once your optimal EPAP min is finally reached. At this point I'm also thinking EPAP min 6, 8, and 10 experimentally paired with PS min 3, 4, and 5 might make for a better exploratory grid for you and your doctor to try together.

If it were me I'd strongly prefer getting in a knowledgeable lab that can properly titrate that autoSV Advanced model. THEN I'd consider fine-tuning with EPAP Min and PS Min exploratory grids from there with doctor approval...

[JIMCHI]

If I raise the EPAP Min to 6, 8, or 10, should I raise the EPAP Max from 15 ?

[-SWS]

If it were me I'd leave the EPAP max capped at that default value of 15. The algorithm won't find enough residual snore, FL, or OA in your case to raise EPAP close to 15 anyway...

[JIMCHI]

I guess I don't understand why, when my patient triggered breaths % drops so low for so much of the night, that my AHI doesn't jump way up. Doesn't that low % mean that the machine was taking over my breathing for almost 20% of the night? I will start a new "trial" tonight using EPAP Min at 6 and PS Min at 3.

[-SWS]

I guess I don't understand why, when my patient triggered breaths % drops so low for so much of the night, that my AHI doesn't jump way up. Doesn't that low % mean that the machine was taking over my breathing for almost 20% of the night?

Yes, the machine kept your residual AHI in check by backing up your missing breaths...

That experiment demonstrated that:
1) using PS Min of 5 your machine needed to back up your missing breaths 7%, 3%, and then 7% of the time, but
2) using PS Min of 6 your machine needed to back up your missing breaths 14% and then 19% of the time

So your spontaneous respiratory drive behaved better at PS Min of 5. At PS Min of 6 a much more significant iatrogenic effect on your respiratory drive was introduced...

[JIMCHI]

Put EPAP Min at 6 and PS Min at 3 (leaving all other settings alone) for last night and my AHI jumped to 17, % Triggered was 94% and Minute Vol was 7.9

What does this tell us? Should I try this setting for another night or two? I feel like I have jet lag today- probably a D+ on a scale of A to F.

[-SWS]

Put EPAP Min at 6 and PS Min at 3 (leaving all other settings alone) for last night and my AHI jumped to 17, % Triggered was 94% and Minute Vol was 7.9

What does this tell us?

Perhaps fewer iatrogenic central events and more primary obstructive events to account for that AHI jump paired with improved spontaneous trigger rate. It's hard to guess at patterns with 8 of 9 exploratory cells still outstanding on your grid...

Should I try this setting for another night or two? I feel like I have jet lag today- probably a D+ on a scale of A to F.

If I felt that way I'd move on to the next row or column---setting EPAP min at 8 or setting PS Min at 4.

Here are some of the dynamics you might encounter in an exploratory grid like that:
- as PS Min decreases: a) iatrogenic central events might decrease, but b) primary central events might increase, and/or c) obstructive events might increase
- as PS Min increases: a) iatrogenic central events might increase, but b) primary central events might decrease, and/or c) obstructive events might increase
- as EPAP Min decreases: a) iatrogenic central events might decrease, but b) primary central events might increase/decrease, and/or c) obstructive events might increase
- as EPAP Min increases: a) iatrogenic central events might increase, but b) primary central events might increase/decrease, and/or c) obstructive events might decrease

The classic xPAP approach to treating CompSAS has been to first address obstruction---mainly with EPAP----and then to address central events with PS and backup rate. However, we already discovered that increasing PS Min introduces/worsens an iatrogenic effect on your respiratory drive when going from 5 to 6---albeit while EPAP Min was low. So the purpose of the exploratory grid is to: 1) attempt to pattern-flush or isolate some of those ulterior dynamics, but more importantly 2) discover WHERE in that exploratory grid all your SDB components/dynamics are best treated while being minimally exacerbated. That was the essence of my earlier comment about trying to find an optimal "treatment saddle point" somewhere in an exploratory pressure grid like that.

Please know that I improvised that exploratory grid search method, so caveat emptor. Make sure your doctor is in the loop...

[Mr Bill]

...That comment about variability reminds me... JIMCHI, I'd suggest trying to keep as eye on sleep position if at all possible. Supine sleeping can exacerbate your obstructive component while side sleeping can exacerbate your central component. As it turns out, one or the other might be more destabilizing for you....

Say, I was just rereading this whole thread and this part of one of your post jumped out at me. I find that I have to sleep on my back to get to sleep and if I turn in the night to either side while sleeping (I still sleep really light so I know I'm doing it) then I see all sorts of pressure excursions and hyponeas the next morning. So, for your observation about side sleeping, I can feel its true if I try to side sleep while falling asleep, but I'm curious; why is it true?

[JIMCHI]

Well, after 3-1/2 months I thought I would give an update to everyone who tried to help earlier.

I continued to try all different settings for a minimum of 3 nights each and continued to have widely varying AHI's. I also tried forcing myself to sleep on my side for 4 nights and that did not change anything. Earlier this month I went to see a new sleep doctor located 150 miles from where I live, so as not to land up at the same sleep clinic or anyone associated with my previous sleep doctor. She was amazed by the variances in AHI's. She is going to have me do an at home sleep study for 2 nights to see if any new information can be gleaned. She also noticed that my normal breathing is noisy and that my voice has an abnormality to it. This had also been noticed by my allergist. Both said it was not coming from my lungs but seemed to be in my trachea. So, I had my ENT doctor put a scope down my trachea and he saw no abnormalities. Next step, in addition to the at home sleep study, will be to have full pulmonary function tests (not just spirometry). This will all be done the middle of July.

In the meantime, I have managed to find settings which seem to have minimized the wide variations in my AHI's. At settings of MaxPres=28, EPAP Min=6, EPAP Max=15, PS Min=5, PS Max=15, backup rate=auto and flex=0. My AHI's have stabilized between 10 and 12. I am still not feeling like I think I should feel using a $6000 VPAP machine. My understanding is that to be considered "successful" my AHI's should consistently be 5 or less and I should not be feeling somewhat worn out and tired on 75% of my days.

Interestingly, I went for my 6 mos. checkup with my pulmonologist (who is not a sleep specialist) and showed him all my data. He said I'm on data overload. He said he doesn't even recommend treatment for anyone whose AHI's are 16 or less, so if my machine is getting the AHI's below 16 maybe I just ought to live with it. He kind of made me feel that I'm wasting my time and money pursuing this.

[JohnBFisher]

Greetings JIMCHI ! Thanks for the update. I will respond to your post in an out of order sequence:

... Interestingly, I went for my 6 mos. checkup with my pulmonologist (who is not a sleep specialist) and showed him all my data. He said I'm on data overload. He said he doesn't even recommend treatment for anyone whose AHI's are 16 or less, so if my machine is getting the AHI's below 16 maybe I just ought to live with it. He kind of made me feel that I'm wasting my time and money pursuing this. ...

Remember. He is NOT a sleep specialist. As to whether you are wasting time and money, let me ask a few questions.

• Do you feel as if you are well rested in the morning?
• Do you feel as if a truck ran over you when you awaken?
• Do you feel somewhere in between the two?
• Do you have uncontrolled high blood pressure?
• Do you awaken with headaches?
• Do you have other metabolic problems (overweight, high blood glucose, diabetes, etc.)?
• Are you able to sleep well for more than six hours a night?

Only if you answered "Yes" to the first question and "No" to ALL of the rest of the questions would it be a waste of time and money! A "Yes" to any other question than the first would, in my opinion and experience, warrant investigation.

How do I know that? I fought with central apnea type problems for years. I finally was VERY desperate to get it addressed. I was sleeping only three to four hours a night. I would awaken with HORRIBLE headaches. I took Ibuprofen to help with that. I had uncontrolled high blood pressure. It was not until I started the ASV unit that it improved. And unfortunately, the Ibuprofen with the high blood pressure damaged my kidneys.

So, yes. It matters and should be addressed. Unless a doctor is a specialist in that area (in this case sleep medicine), their opinion is not really valid. They don't know the damage that poor sleep can do to a body. But if you doubt it, just remember that sleep deprivation is used as torture the world over!

... I continued to try all different settings for a minimum of 3 nights each and continued to have widely varying AHI's. I also tried forcing myself to sleep on my side for 4 nights and that did not change anything. ...

Good for you for trying to work through the various combinations. It will in fact make it easier to get to the bottom of your sleep problems. You've eliminated a lot of possible issues.

... Earlier this month I went to see a new sleep doctor located 150 miles from where I live, so as not to land up at the same sleep clinic or anyone associated with my previous sleep doctor. She was amazed by the variances in AHI's. She is going to have me do an at home sleep study for 2 nights to see if any new information can be gleaned. ...

Sounds like a good idea. It is probably time for a little more data. More than just what the machine can provide.

... She also noticed that my normal breathing is noisy and that my voice has an abnormality to it. This had also been noticed by my allergist. Both said it was not coming from my lungs but seemed to be in my trachea. So, I had my ENT doctor put a scope down my trachea and he saw no abnormalities. Next step, in addition to the at home sleep study, will be to have full pulmonary function tests (not just spirometry). This will all be done the middle of July. ...

You might want to look into Vocal Cord Dysfunction (VCD):

http://emedicine.medscape.com/article/137782-overview

Remember, I am not and do not claim any medical knowledge. However, my neurological problem includes VCD as one of the symptoms. So, your description reminded me of that set of symptoms. It certainly does not hurt to look into it. In fact, it sounds as if your doctor thinks it should be investigated.

... In the meantime, I have managed to find settings which seem to have minimized the wide variations in my AHI's. At settings of MaxPres=28, EPAP Min=6, EPAP Max=15, PS Min=5, PS Max=15, backup rate=auto and flex=0. My AHI's have stabilized between 10 and 12. ...

Good for you. Less variability is a good thing.

... I am still not feeling like I think I should feel using a $6000 VPAP machine. My understanding is that to be considered "successful" my AHI's should consistently be 5 or less and I should not be feeling somewhat worn out and tired on 75% of my days. ...

Which gets to the heart of my questions above. If you still feel miserable it might mean that either you are NOT sleeping well and it will impact your health, or that some other condition is contributing to the "poor" feeling. Either way, they should be investigated. It is possible there is nothing the doctors can do. However, if they can do something to help you feel better, it is worth the effort.

As always, these answers are just in response to my question "What would I do if I were in your shoes?". I am not a medical professional. I just try to be a professional user of the xPAP therapy!