Respironics Omnilab advanced - 2cm pulses - is it normal?

[bailachel]

I'm sorry that you had such a bad time at your titration. I hope the information they were able to get will be of help to you.

I have never felt the pulses sent out by my PR1. I only know they happen because I see them on the waveform report. In my case, they only happen when I am asleep and usually only about 2-3 times per night. I'm running the PR1 in CPAP mode.flow = 10 and Cflex+ = 3.

[DreamDiver]

Thanks everyone for your replies. I've tried to respond below.

DD, do you happen to remember my recent fishing expedition about your possible hypersensitivity?
viewtopic.php?f=1&t=51219&st=0&sk=t&sd= ... li#p471855

S9 FOT is definitely your better bet between those two central-apnea detection methods IMHO.

You may be right.

...The FOT 1 CM pressure on the S9 is shaped (shark fin wave form) which makes it easier to take anyway. The extra FOT 1 CM is delivered within the sharkfin wave form already being delivered (being part of what Resmed calls EasyBreathe). On the Respironics machines the shape of the sampling pulse is (from my educated guess) more squared (but not purely square - i.e. steep slope up then level then steep slope down). From what I know, that shape wave form is more easily sensed by users. The normal bipap epap to ipap pressure jump is similar but that slope can be adjusted with variable rise time settings. It seems the open airway sampling pulse risetime isn't settable. Being 2 CMs shouldn't be too big a deal as a Bipap Auto SV will whack up pressure by 3 CMs within a single breath (but adjustable by normal risetime settings). ...

I decided to take an even closer look at the FOT method for the S9. In the below image, a number of things become apparent.

• The below image is a four-second span.
• S9's FOT is about 1/4 the pressure at the mask as compared with omnilab advanced - only about half a cm.
• The pressure waves come at about 4.33 pulses per second. How does that frequency compare to delta?
• The pressure waves look distinctly sine curved. They may have a slightly different curve to them, but they are certainly not square or abrupt, as is evident even at 25 event captures per second.
• I'm comparing mask pressures, since this is where it's felt. Compare respironics (in green) with the mask pressure wave (the lower of the two shorter waves, also in green -- .5 cmH20). They are entirely different in character.
• EDIT: This data is derived from two .edf files from my S9 and viewed using the EDFBrowser. Stuff in red, yellow and green are my additions. The *BRB.edf files include both flow and pressure at mask. The *EVE.edf files contain event data.

... I only experience the pulse if I haven't breathed in roughly 10 seconds. I am only conscious of it when I am awake. When I am asleep, I don't seem to notice it.
...

I will see if I can post some "traces" later on today.

You are indeed fortunate. I guess a lot of people really don't notice it. That's probably why so few people actually notice FOT on the S9.

Try a post on binarysleep.com if you don't find any additional info.... maybe some of the other more experience tech's on that site have more knowledge about the Omnilab.

I'll check it out. Thanks.

DD, you _sure_ you don't want to try out that 420E?

By the way, stupid question: are both Resmed and Respironics now using the FOT method to do "clear airway" detection?

No idea if what Respironics is doing is considered FOT. The S9 is using FOT according to the ResMed site. Respironics' method is definitely a 'hammer' compared to the 'bell' used in the S9. Also S9 clearly states that it is detecting central apnea, even if it should be called 'clear airway' apnea according to some. And you're right - they do seem to have that much confidence it its accuracy. I'd love to find out what the exact accuracy rate is supposed to be as compared with the 420E.

Some random info I found, may be interesting in light of the 'sensitivity' issue...

Thanks for the link. I'll definitely check it out too.

I have never felt the pulses sent out by my PR1. I only know they happen because I see them on the waveform report. In my case, they only happen when I am asleep and usually only about 2-3 times per night. I'm running the PR1 in CPAP mode.flow = 10 and Cflex+ = 3.

As with park_ridge_dave, you too are fortunate. Thank you for the well wishes.

DD, as promised, here is a snippet of my results from last night. Note the pulses usually stop after I am asleep unless I have an episode of Periodic breathing or a CA event.

Thanks for this park_ridge_dave. I wonder - is it possible to view the waves any closer at higher magnification? (Not just blowing up the pdf - but rather - higher resolution?)

[park_ridge_dave]

DD

I don't think there is any way to crank up the resolution on the report. It appears to put out the PDF only at one resolution. And as you stated, zooming in an a PDF doesn't "cut it"

I am using EP 2.2 to get the displays so maybe someone else has a "secret" that would enable more resolution on the data.

The pulse could well be some series of quick "puffs" but it feels like a sustained pulse to me.

Sorry I can't be of more help.

Dave

[DreamDiver]

...The pulse could well be some series of quick "puffs" but it feels like a sustained pulse to me.

Sorry I can't be of more help.

Dave

park_ridge_dave,

Actually, it's been very helpful. From the six-minute epochs on your image, we can imply that each pulse is indeed on the order of one to three seconds long.

Cheers!

[-SWS]

What a nice graphical comparison from DD:



For newcomers-- we are comparing Resmed and Respironics central-apnea detection techniques:
1) the green Respironics mask-pressure pulse (labeled "Respironics 'clear airway apnea' detection...") is being compared with
2) the Resmed mask-pressure oscillations (labeled ".5cm H2O average")

You can see by the steep difference in amplitude or height, how DD found the Respironics pressure probe to be much more noticeable.

I don't think the method Respironics employs to detect "clear airway" apneas is really FOT. Rather, they source a coarser 2 cm pulse and measure whether mass flow occurs or not---very basic. By contrast Resmed uses oscillations to calculate a complex airway impedance that can approximate degree of airway closure.


Again, DD's sensitive response to that taller Respironics pressure pulse seems to be the rare exception rather than the rule. DD were sleep-onset problems or PSG-recorded spontaneous arousals ever a problem for you? I'm wondering if you and your doctor need to put your heads together to experiment with ways to get your arousal threshold higher. I know you don't really favor pharmaceutical solutions...

[dsm]

park_ridge_dave

Interesting data chart you posted. Which version of Encore Pro are you viewing/printing that with ?

It has more detail in it than I have seen before from Encore Pro.

DSM

(always learning something new)

[DreamDiver]

... DD were sleep-onset problems or PSG-recorded spontaneous arousals ever a problem for you? I'm wondering if you and your doctor need to put your heads together to experiment with ways to get your arousal threshold higher. I know you don't really favor pharmaceutical solutions...

It's a good question - I don't know enough to read between the lines from what they say on a PSG report. What other than 'spontaneous arousal' would I look for? I have atypical reactions to a lot of pharmaceuticals. It forces me to be cautious, but perhaps I should revisit the idea. Understanding that none of us are doctors - what have others found useful for this kind of hyper-awareness/sensitivity?

Which version of Encore Pro are you viewing/printing that with ?

It's EP 2.2. This kind of data only shows up with the System One Elite/Auto and apparently the omnilab advanced and bipap autosv advanced, etc.

[-SWS]

... DD were sleep-onset problems or PSG-recorded spontaneous arousals ever a problem for you? I'm wondering if you and your doctor need to put your heads together to experiment with ways to get your arousal threshold higher. I know you don't really favor pharmaceutical solutions...

It's a good question - I don't know enough to read between the lines from what they say on a PSG report. What other than 'spontaneous arousal' would I look for? I have atypical reactions to a lot of pharmaceuticals. It forces me to be cautious, but perhaps I should revisit the idea. Understanding that none of us are doctors - what have others found useful for this kind of hyper-awareness/sensitivity?

Well, you're undoubtedly going to be seeing your doctor soon to discuss your recent Omnilab Advanced experience. I'd use your atypical sensitivity to the 2 cm pressure probe as an inroad to explore the entire concept of sleep arousals with your doctor:

1) Was spontaneous-arousal scoring even part of the methodology employed by your past PSG studies?
2) If so, did you sleep long enough to record any?
3) Did arousals seem to affect your sleep architecture during any of your titration studies?


We're going to get a dedicated thread w/poll going real soon about the topic. I want to wait until Sleeping Ugly returns to pick her clinical ideas about the topic as well...

[park_ridge_dave]

DD et al,

From a strictly controls engineering perspective, the ResMed unit has it all over my PR System One. The sampling rate on the software seems much better and the algorithm used to "compute" the apnea events seems much more sensitive. As I said, however, I am lucky as the pressure pulse doesn't seems to cause me to wake up.

DD you have my sympathy good luck.

Cheers,

Dave

[echo]

... DD were sleep-onset problems or PSG-recorded spontaneous arousals ever a problem for you? I'm wondering if you and your doctor need to put your heads together to experiment with ways to get your arousal threshold higher. I know you don't really favor pharmaceutical solutions...

It's a good question - I don't know enough to read between the lines from what they say on a PSG report. What other than 'spontaneous arousal' would I look for? I have atypical reactions to a lot of pharmaceuticals. It forces me to be cautious, but perhaps I should revisit the idea. Understanding that none of us are doctors - what have others found useful for this kind of hyper-awareness/sensitivity?

Well, you're undoubtedly going to be seeing your doctor soon to discuss your recent Omnilab Advanced experience. I'd use your atypical sensitivity to the 2 cm pressure probe as an inroad to explore the entire concept of sleep arousals with your doctor:

1) Was spontaneous-arousal scoring even part of the methodology employed by your past PSG studies?
2) If so, did you sleep long enough to record any?
3) Did arousals seem to affect your sleep architecture during any of your titration studies?


We're going to get a dedicated thread w/poll going real soon about the topic. I want to wait until Sleeping Ugly returns to pick her clinical ideas about the topic as well...

DD, for me the biggest reduction in hypersensitivity occured as a combination of the following (and I don't know which has the largest effect, I only give a list in temporal order from oldest to most recent):
- Staying away from wheat (and then all the other food intolerances that have subsequently developed)
- Finding my sweat spot pressure of 10.5 cm, anything lower is no good, anything higher causes way too many central's (or i can't breathe against it), and APAP just drives me batty (mostly because it keeps the pressure too low, unless I set it to 10.5, in which case I'm better off in CPAP mode, but also because the changes in pressure sometimes wake me up)
- Pretending like I'm hypoglycemic and avoiding sugar spikes (I tested negative for diabetes but who knows)
- Sleeping enough. I need 9-10 hours. Any less and I'm cranky. Who knows if I'm still paying off "sleep debt".
- Hypothyroid treatment

I would be interested in knowing other ways to reduce the sensitivity too!

I know you asked DD these questions -SWS but I'm going to answer anyway
For what it's worth.... I remember that from my sleep study we conjectured (translation issues) that I also had a lot of spontaneous arousals. I also have a high breaths-per-minute (will that be on the poll too -SWS?) but only at night (I think). During my titration I had only 202 minutes of sleep time including 14 minutes of REM, and AHI of 11, but 30 arousals+awake index, with 28 changes in sleep state and 3 min in Stage 1 sleep. During my initial PSG I had slightly more arousals+awake (38) than AHI (35), and most of my AHI are actually H's and those are mostly in non-REM sleep.

I think there are a lot of interesting parallels between our two cases, DD, especially looking at the food intolerances. Mine are (have been) mostly grains (wheat/corn), or nightshade plants, but also nuts, and even for a while pork. They tend to come and go and change quite a bit.

Waiting for -SWS's poll on the edge of my seat

[dsm]

Thinking out loud re the sensitivity to pressure changes problem ...

I have long wondered if those of us who have underlying UARS issues (such as chronic or severe nasal congestion) are going to be far more affected by the sensitivity of some brands of bilevel to the ipap to epap cycling. Having UARS and OSA together also seems a probability for some people. I believe it is commonly accepted that UARS eventually leads to OSA.

This is an issue that has cropped up often in that certain of us would feel that particular bilevels kept cycling too early. I am certain that anyone with UARS would be more susceptible to such an issue. Reason I stay with a F/F mask is that despite Nasonex, my breathing varies between nose & mouth. So someone with UARS may be prone to hypopneas which in the new 'Advanced' machines, is going to trigger airway probing.

It seems logical to me that any sudden pressure change such as 2-3 second 2 CMs spike, could also be uncomfortable to some UARS sufferers as well as any people with pressure sensitivity from some other cause.

Again, just mulling over the issues.

DSM

[Muse-Inc]

2 cmH20 ! OMG, I'd never have fallen asleep!!! That's a horrifically large change. DD, makes me wonder if you and I and it sounds like a bunch of us have this hypersensiticy thing going on that's compromising restful sleep. Lousy sleep study! At least they know they've got equipment that compromises falling asleep for at least some people. I think they owe you another study using equipment that won't pulse 2 cmH2O; the one you had was useless in identifying what was occurring when you sleep.

-SWS start the poll & thread..maybe collectively we can share ideas and come up with some things to try to help each other.

I'm hypersensitive to light, sound, touch (circulating air. wind), scents (when I'm not congested). I have hyper-reactive skin too, easily irritated. Have always been easily awakened 'cept w untreated apnea, then I slept like the dead hahahaha (not so funny actually). Also have a strong startle reflex, even fainted a few times as a teenager. Had parasomias as a child (talked & walked when sleep). No siblings, had an imaginary friend for about 2 years. I had food allergies as a child, now just sensitive to grains, esp wheat which tends to congest mu nose. Tendency to be hyper, wired all the time...challenging for me to be calm & quiet...serene has seldom been used to describe me this past decade as I've danced with apnea. Sound familiar?

Oximeter...dam# it, lost last night's data, got distracted and hit the wrong button....irritates the he## outta me when I do that, esp last night 'cause the SpO2 alarm went off quite a few times. I usually ck the LED and sure enough at least once I was <88%. Wonder how many of the other times it went off last night when I didn't ck and I was desatting and not just 'cause I broke contact for a sec? *sigh* AHI=0.5 all hypops; median pressure in mid 8s, 95centile was 10, max 11 all typical; leak lower than usual. Things I've noticed: after hypops my pressure often increases a bit. I had a 14 sec apnea when I had been bumping the top of the scale on SpO2 so maybe a central...had enough O2 and didn't need to breathe...maybe? I seldom have apneas and when I do they're usually 10-11 secs...sure wish I knew how long my hypops actually lasted, that little mark can't be time in ResScan 3.7. Haven't noticed a pattern yet between SpO2 & hypops. Pulse will sometimes increase for no apparent reason, not sure that that is...REM maybe? My SpO2 stays mostly in the mid-high 90s (daytime goes down to 92 when I start focusing & breathing slows & gets shallow ( I tend to slump when I focus)...hypoventilation of obesity maybe? Will continue to collect data, will post when I have more data.

[DreamDiver]

...I'm hypersensitive to light, sound, touch (circulating air. wind), scents (when I'm not congested). I have hyper-reactive skin too, easily irritated. ... Also have a strong startle reflex, even fainted a few times as a teenager. Had parasomias as a child (talked & walked when sleep). No siblings, had an imaginary friend for about 2 years. I had food allergies as a child, now just sensitive to grains, esp wheat which tends to congest mu nose. Tendency to be hyper, wired all the time...challenging for me to be calm & quiet...serene has seldom been used to describe me this past decade as I've danced with apnea. Sound familiar?

Light sensitivity is pretty normal - I like my sunglasses on sunny days. Sound sensitivity is pretty high. Startle reflex is high, but no fainting. I sometimes startle out of sleep for no apparent reason. No imaginary friends. Tactile sensitivity is a big one. I guess one of the good things about that is I can feel even tiny ticks crawling on me before they usually get a chance to bite. Most bandaids and sticky tape used in hospitals causes redness and irritation - including their so-called 'hypo-allergenic' tape. Oddly, the eeg sticky gels don't. 3M Nexcare bandages seem okay too. I used to find alternative ways through department stores before they stopped attacking passers-by with the cologne department. Food sensitivities are always an interesting challenge. I've been described as 'intense'. I don't have the energy to be wired.

[DreamDiver]

...
- Staying away from wheat (and then all the other food intolerances that have subsequently developed)
- Finding my sweat spot pressure of 10.5 cm, anything lower is no good, anything higher causes way too many central's (or i can't breathe against it), and APAP just drives me batty (mostly because it keeps the pressure too low, unless I set it to 10.5, in which case I'm better off in CPAP mode, but also because the changes in pressure sometimes wake me up)
- Pretending like I'm hypoglycemic and avoiding sugar spikes (I tested negative for diabetes but who knows)
- Sleeping enough. I need 9-10 hours. Any less and I'm cranky. Who knows if I'm still paying off "sleep debt".
- Hypothyroid treatment

I would be interested in knowing other ways to reduce the sensitivity too! ...

Wheat intolerance seems to be growing at a rate similar to that of peanut intolerance in the general population. Ever notice how many elementary schools no longer serve anything with peanut ingredients in them, let alone allow students to bring peanut products to school? I suspect it has something to do with GMO foods.

As to the centrals -- even though the study seems to have been somewhat flawed, it does make me question for myself whether I've self-titrated too high. The problem is, AHI ordinarily increases as I move away from my current sweet spot of 10.4. But AHI isn't the only factor. I'm going to continue looking at Spo2 as an indicator too.

It's nearly impossible to find even simple canned vegetables without sugar, or worse, high fructose corn syrup in them. Look for kidney beans, black beans, etc., in the canned vegetable aisle. How many brands can you find with no form of added sugar in them? It's often among the first listed ingredients, indicating that the amount is fairly high. It's hidden even in the least processed of our prepared foods.

I would love to be able to sleep longer, but it seems like I only get naps. I'll get about five hours, and I'm done. So I wake up, do some stuff and go back to sleep for a couple hours. Trying the sleep hygiene thing where I force myself to go to bed at a specific time only forces me to lie there all night. I'm done with that. All it does is make the wheels spin in my mind. I go to sleep when I'm tired. I really would like to be able to sleep through the night like I used to.

Hypothyroidism seems to have been a recurring theme recently on the forum that has gotten my attention again. I ruled it out a few years ago prior to starting CPAP because the docs said I didn't have it. Now I'm not so sure. I think this avenue is again definitely worth exploring. There seems to be a lot of cross-over between fibromyalgia-like pain and other symptoms with hypothyroidism, diabetes and sleep apnea.

[dsm]

DD

I kind of identify with you - symptoms & analytics.
Very interesting posts & no slouch when it comes to details.

Cheers

DSM