No Answers Yet For Problems With ASV

[Paper_Nanny]

However, if the tests are the same ones NotMuffy recommends, done with the proper equipment, and administered as competently as he would perform them (tall order, that!) the wait will pay off in giving you a solid start in finding out What Needs Fixing Before Trying To "Fix" It.

So, NotMuffy, how's about I come to where you are, or you come to where I am, or we meet somewhere in between, and you do the tests. That way, I will get all the ones you are recommending, done with proper equipment, and administered competently.

Deborah

[dsm]

Deborah,

Again, the following story is in sympathy - When self 1st went on cpap it was with a Respironics Remstar Auto recommended to me by Rested Gal. It was IMHO probably the best cpap type machine on the market at the time. This was back in 2005. The sleep specialist I saw had opined before my sleep study that he doubted I had OSA after his 1st examination. But on seeing him again he said 'wrong - you have an ahi of 40'. In fact in 1989, had done a sleep study at this same hospital & been told 'no OSA'.

At the time I got the machine the hospital, in conjunction with the Respironics agent for the country, were doing a study of 100 people, 50 who were to be given an intro to cpap therapy at a series of 3 meetings where spouses were invited to attend, and 50 who were handed their cpap & given no intro. They wanted cpap data so for the next 4 weeks the machine although an auto, was set as a cpap.

At 1st it seemed beneficial also after 4 weeks switched to auto mode & set in range of approx 8-15. Wife then began commenting that self was resisting the machine. "The machine whirs, you stop breathing, I push you & all gets back to normal". Daytime drowsiness at work was right back to as before. Self was feeling a bit desperate as the issue that began to scare me was remaining employed at a well paid job that requires lots of brain work. That feeling of fear re keeping alert was also depressing especially as the cpap/auto whilst it seemed great for the 1st 8 weeks, was going nowhere.

With some level of rising anxiety self obtained a very sophisticated Knightstar PB330 Bilevel 'ventilator' machine that had S/T support & thus had a backup rate which would ensure that stopping breathing would be dealt with & was able to get back to an acceptable level of daytime wakefulness. Was starting to believe the situation was under control. Did a whole lot of experimenting over 6 months & with the help of folk here at cpaptalk, was able to tune the machine. In 2007 went back in for another sleep study & the specialist said stay with your Bilevel as you seem to have it set up ok & it is working.

But this PB330 BiLevel didn't have nightly data & self was really 'flying blind' & so then obtained a Resmed VPAP III S/T & at the same time a Respironics Bipap Pro 2 (followed by a Respironics Bipap S/T). Both the Respironics Pro 2 & S/T had a quirk whereby my shallow nasal breathing was messing up the tracking & it would repeatedly try to switch from breathing out to breathing in before I was ready. Very frustrating. Intolerable in fact. The Resmed Vpap III machines characteristically had a horrible high-pitched whine that didn't bother self as much as wife. It was so irritating to her that she would inevitably go sleep in another room anytime I used those Vpap III machines but they had fantastic nightly data. Next self got a Respironics Bipap Auto but it didn't have backup rate & that proved problematic again. Then came across a Bipap AutoSV & whilst expecting it to have the same tracking problem experienced with the Bipap Pro 2 & S/T, it worked like a dream. For the next 6 months it seemed to be a gift from the gods. Then self got an opportunity to buy a very low priced Vpap AdaptSV. Out of curiosity, tried it & was horrified at how much it tried to control breathing rate. The mask leaked & squeaked & it was hard to get any deep sleep. The Bipap Auto SV by comparison became my 'dream machine'.

Had the story of daytime drowsiness & foggy headedness ended there all would have been well. But it returned - no amount of tuning the Bipap Auto SV prevented this and, along with that came the panicky feeling that not even the best machine available was doing any good. Out of sheer desperation, got a better mask (quattro - just released at the time) & again tried the 'horribly controlling' Vpap Adapt SV. The daytimes improved but using the machine had serious ups & downs. When it was good it was very very good but when it was bad it was horrid. For a time it was a case of switching between it and the Bipap AutoSV. Then as mentioned in an earlier post - got a pad-a-cheek anti-leak strap & suddenly the Vpap Adapt SV kicked in with decent sleep & behavior. 18 months later self has *no* fear of becoming employable from cpap related fogginess. There is now none of the repeating patterns of deep drowsiness & foggy headedness that followed switches between the earlier type machines. Today, some can occur mildly but not for more than a day or so & it seems more related to other factors such as lifestyle activities.

Point of the above story is again to paint a picture of a journey and discovery. Again as mentioned in earlier posts, there were several realizations that these machines are not perfect but are evolving at a very rapid pace. The whole SDB story is evolving. It is only in recent times that Complex SA has become understood. It seems quite likely that more such discoveries will be made of complications arising from particular xPap modalities (Cpap <=> AutoCpap <=> Bilevel <=> Auto Bilevel <=> ASV <=> ASV with Varying Epap for OSA <=> future modalities ).

In 2005 few machines delivered nightly data. It was a feature of the Auto machines had as they needed to analyze a persons breathing in order to decide when to adjust the pressure. It was a simple step to add the ability to download that nightly data & put it into reports. Also in 2005 many clinics were leery of Autos & my RT & the hospital (then the leading Sleep Clinic in the country) all warned against using them until they were 'proved'.

So if we take a snapshot of that year, not that many people had AutoCpaps let alone machines that provided nightly data. In fact at that time the only real source of nightly data was from sleep studies. Even for those of us who obtained the software when we could get it, trying to make sense of it was very difficult. That was and remains one of the great value propositions offered to us participants at cpaptalk because here we had people who could help us interpret the data and learn what it meant. So since 2005 more & more cpap users have insisted they have a machine that provides nightly data or reports & more folk are able to make sense of it. This in turn has put pressure on RTs & Doctors to better understand the data because a lot of folk who spent time here learning, were able to go back to their RTs & Docs & tell them things they didn't know or didn't full appreciate. The manufacturers have built more reporting into the displays of the machines. That trend of analyzing the nights data & offering interpretations via the display can be expected to continue for a long time into the future. We users will drive that.

This whole cpap therapy scene is evolving in many ways. The clinics are getting more sophisticated & good RTs & specialist are learning more about field use of these machines due to the growing volume of reports & data becoming available and the growing awareness of the information by us actual users.

This is a journey and it does have light at the end of the tunnel even if at times that light is only a gap in the tunnel not the end of it.

Cheers

DSM

[dsm]

Following on the prior post - it has always seemed to me that my experience plus that I have read from many other folk (including your recent comments Deborah) that many of us seem to go through a 'honeymoon period' with our new cpap machine but some of us find our selves quickly back where we started.

I would love to see some studies carried out on if this is an identifiable 'syndrome'. Is it something that can be identified and a cause put forward to describe why & how it happens. Question being - "Do some people have respiration patterns that can override the benefit of airway stenting, or bilevel support or ASV pressure support ?" (perhaps there is a simpler question).

Speaking for myself, had it just occurred with one mode of machine, I might lean towards the cause being just mode related, But having seen it & experienced it across multiple modes (but to greatly varying degrees), am thinking it must be related to some other respiratory factors.

Is it possible we get used to a particular mode then revert to 'bad/negative' breathing habits or patterns ?

Wife has *often* commented that she was sure self was in a struggle with the machine & in the early days self was winning. For me, being asleep makes it hard to see this (if it is feasible) as a 'conscious' (knowing struggle) activity.

DSM

[NotMuffy]

And how about a NIF?? Only if it is ordered separately. And, even then... Well, it's hard to explain, she said. They don't actually have a NIF Testing Machine. They sort of improvised one. Well, not all of them, pretty much just Ki did. It is accurate, but it's something Ki made out of a pneumometer.

First of all, you need to get

a set of Maximum Inspiratory and Expiratory Pressures.

Just about everybody "rigs up" the mouthpiece, don't worry about that. As long as they know what they're doing and the meter is accurate it'll be fine.

By "knowing what they're doing", there is a fairly specific technique:

Determinations of respiratory muscle pressures are a quick and noninvasive means of assessing respiratory muscle strength.

•MIP: Patients breathe through a flanged mouthpiece with nose clips in place. Patients are instructed to exhale to RV. At RV, a valve or shutter is closed and the patient is coached to inhale as forcefully as possible. Maximum pull should be maintained for 1-2 seconds. A standardized leak must be present in the measurement system to eliminate significant overstatement of MIP by allowing the cheek muscles to contribute to the measured pressures. Initial maximum negative pressures that cannot be maintained for 1 full second are ignored.

•MEP: Patients breathe through a flanged mouthpiece with nose clips in place. Patients are instructed to inhale to TLC. At TLC, a valve or shutter is closed and the patient is coached to exhale as forcefully as possible. Maximum push should be maintained for 1-2 seconds. Initial maximum positive pressures that cannot be maintained for 1 full second are ignored.

So if the instructions are "Here, suck in on this" wave the instructions at them.

[NotMuffy]

The PFT parameters are fine. Looks like they're going to toss you in the booth to measure lung volumes. Quite accurate. As you previously noted, this is a baseline test that you'll need for comparison should respiratory symptoms appear later. However, MIP and MEP are probably more sensitive to monitor this. Diffusion and FRC may offer insight to some of the bizarre machine response.

You could ask to do some supine measuremenets, but that's probably pushing it.

[dsm]

So back to being existential, the graphs look scary but its not necessarily as bad as it looks. Reminds me of being moved to Namibia, Africa when I was 10 years old. I should have been entering 5th grade. They tested me and then set me back a full grade for not being up to level in the language Afrikaans. Metaphorically, the ASV is scoring you very heavily for erratic breathing. But, despite the poor test scores, you are getting some sleep with this assistance. If you have a while to wait before getting the tests NotMuffy suggested; which mode (BIPAP or ASV) is giving the better oximetry? I would try that for the time being and not worry too much about the EncoreViewer graphs. In other words try not to be too anxious about the graphs from either mode. Both seem to be giving you some sleep and that is far better than none.

@DSM and NotMuffy: I had no idea that spinal fluid played a role in CO2 respiration regulation. This is fantastically interesting.

Mr Bill

Is this link along the lines of your comment re spinal fluid & respiration ?
http://www.nda.ox.ac.uk/wfsa/html/u02/u02_011.htm

This is an area way outside my expertise but right in NotMuffy's domain.

Cheers DSM

EXTRACT:

Afferent Supply

(1) Central chemoreceptors. Chemoreceptors are cells that respond to chemical stimuli. There are cells in the floor of the fourth ventricle (part of the brain stem) that respond to the acidity of the cerebrospinal fluid (CSF) and the output from these cells influences breathing. The acidity of any fluid is measured by the pH; this is related to the number of hydrogen ions in the solution. The normal pH of the body is 7.4; values higher than this represent alkaline conditions in the body, with a lower hydrogen ion concentration, and values of pH less than 7.4 represent acidic conditions, with a higher hydrogen ion concentration. The cells in the floor of the fourth ventricle respond to the pH of the CSF. An acidic CSF causes hyperventilation this is the reason for dyspnoea with conditions such as diabetic ketoacidosis. An alkaline CSF inhibits the respiratory centre. Carbon dioxide in the blood can rapidly diffuse across into the CSF, and there is a balance between the level of carbon dioxide, hydrogen ion and bicarbonate ion in the CSF. If the carbon dioxide in the blood increases (eg following exercise), then the carbon dioxide, hydrogen ion and bicarbonate ion concentrations increase correspondingly in the CSF. This increase in CSF acidity causes hyperventilation which lowers the carbon dioxide concentration in the blood. A low blood carbon dioxide level (hypocarbia) has the opposite effect and may occur, for example, following controlled ventilation during anaesthesia. This may delay the return of spontaneous breathing at the end of surgery.

[rested gal]

before I go further, I need to make a momentary digression. When Husband and I went to get our marriage certificate, the woman filling out the forms asked Husband where his mother was born. Husband replied, "In Nebraska." Form woman looked annoyed and said, "Well where was it?" Husband said, "I'm not sure exactly where, but it was in Nebraska." Form woman looked quite irritated and shrieked, "In a basket? She was born in a basket? Well, where was the basket?"

followed by the way you slipped this in...

No, no, there's nothing like that. It's all done in a box.
In a basket?
No, in a box!! If you want, I can give you the phone number for the department where the testing will be done. Maybe they can explain it to you.

I burst out laughing. Have I said I love your sense of humor?

Whether you actually said, "In a basket?" to the person on the phone .... perfect timing!

[rested gal]

Also chuckling at some unintended funny stuff:

viewtopic.php?p=613767#p613767

I don't think this self has ever seen another self refer to himself as "self" as many times as that self does.

[dsm]

Also chuckling at some unintended funny stuff:

viewtopic.php?p=613767#p613767

I don't think this self has ever seen another self refer to himself as "self" as many times as that self does.

RG

Glad you got a good laugh

You look nice when you smile

D

[NotMuffy]

What do I want? I want my sleep to be the way it was on the best nights after I got my ASV. I slept well. Deeply. Dreaming. I woke up feeling refreshed, chipper, perky, energetic. And I loved that feeling!! On those nights, my patient triggered breath percentage was high, my AHI was low. I seem to recall that being the way it was for the first 8- 10 weeks.

Interestingly, resolution of the sleep-related breathing instability associated with CompSAS usually occurs after about a month, so this seems quite the reverse of what should be happening.

Your sleep architecture on both sleep studies appear to be heavily influenced by medication effect. Do you have a medication list and a timeline of everything back to the first sleep study?

[NotMuffy]

You could ask to do some supine measurements, but that's probably pushing it.

Let's see if phpBB will pick up all the wingdings:

Pulmonary function in multiple sclerosis without any respiratory complaints
Ayse Altintasa, Tuncalp Demirb, Hande Demirel Ikitimurb, Nurhayat Yildirimb

Abstract

Objectives
Pulmonary complications in severe multiple sclerosis (MS) are often seen secondary to respiratory muscle dysfunction. The development of respiratory muscle dysfunction and its association with disability during the course of MS is unknown. In our study, we investigated the predictive value of respiratory muscle functions and the change in forced vital capacity (Δforced vital capacity [FVC]; FVC upright−FVC supine) to detect deterioration of respiratory muscle functions in the early phase of MS.

Patients and Methods
Twenty-one MS patients with a median age of 34.5±9.45 years were enrolled. Fourteen cases were relapsing-remitting, six were secondary progressive, one was primary progressive type. The mean duration of disease was 10.76±6.6 years. Seventeen healthy subjects with a median age of 40.7±7.6 years were chosen as a control group. Smoking habit was similar in both groups. Pulmonary function tests (PFT), lung volumes, diffusion, respiratory muscle function (, ), mouth occlusion pressure, and indirect sign of respiratory center function (P0.1) tests were performed. PFT were repeated in supine and upright positions.

Results
Our results in the MS group and the control group, respectively, were: diffusion (DLCO: 18.8±4.2 vs. 26.4±7.3mL/mmHg/min), (82.1±26.3 vs. 109.1±23.3cmH2O), (119.2±42 vs. 171.8±50.2cmH2O), P0.1 (2.6±0.7 vs. 4.2±0.7). All parameters were lower in the MS group compared with the control group (p<0.05). In the MS group, FVC values in the upright position were higher than FVC values in the supine position. The difference in FVC values in MS patients between the upright and supine positions (ΔFVC) was also found to be significantly higher than in the control group (ΔFVC 262.3±247.6 (MS), 98.8±179.1mL (CONTROL)) (p<0.01).

Conclusion
Our results indicate the presence of pulmonary dysfunction in MS even in the absence of any respiratory symptoms.

Altintas A, Demir T, Ikitimur H, Yildirim N. Pulmonary function in multiple sclerosis without any respiratory complaints. Clin Neurol Neurosurg. 2007;109:242-246

[NotMuffy]

So, NotMuffy, how's about ...we meet somewhere in between, and you do the tests.

Sure! We'll just load up all the stuff in the Muffenstein pick-up:



and I'll see you in the aforementioned Nebraska!

I've always wanted to see Nebraska!

Probably about as much as I wanted to be dragged up a flight of stairs by the teeth with a pair of Vise-Grips.

[Paper_Nanny]

Interestingly, resolution of the sleep-related breathing instability associated with CompSAS usually occurs after about a month, so this seems quite the reverse of what should be happening.

Yes, it does. <another big sigh> At one time, I was one of those people who systemactically disobeyed the unspoken rules of social behaviour. If someone had been watching me at that time in my life, the observer would have said, "How interesting! What she is doing seems quite the reverse of what should be happening." I wonder now if I went so far with that that on some deep, subconscious level, I decided This Is The Way To Be. And now, my body itself does things that seem quite the reverse of what should be happening.

[I wish I could embed little sound clips into my posts. "I don't know how to stop, no I don't know how to stop" Peter Gabriel, No Self Control...]

Seriously, though... This isn't the first time medical issues, drug reactions, etc. have been labelled as seemingly quite the reverse of what should be happening. I don't know why.

Your sleep architecture on both sleep studies appear to be heavily influenced by medication effect. Do you have a medication list and a timeline of everything back to the first sleep study?

MSD and my neurologist both concluded that drug effect was not an issue. However, I am not sure I trust their opinions on this one. During the appointment with Kurt the Neurologist to discuss just this issue, he said, "I don't know anything about MS that you couldn't find out on your own" and "If you have a sophisticated patient with access to the internet, they could find out more than I could about this, given the limited amount of time available." That was after making me wait for fifteen minutes while he discussed paint colours with the building maintenance people.

Yes, I do have a medication list and timeline from back when both studies were done. I will post it if that would be helpful to you.

Deborah

[Paper_Nanny]

Just about everybody "rigs up" the mouthpiece, don't worry about that. As long as they know what they're doing and the meter is accurate it'll be fine.

By "knowing what they're doing", there is a fairly specific technique:

<snip>

So if the instructions are "Here, suck in on this" wave the instructions at them.

Thank you! I will be printing off those directions and taking them with me, to wave at them, if necessary.

You could ask to do some supine measurements, but that's probably pushing it.

How difficult is it to do supine measurements? Would I need separate Physician's Orders for that or could Simply Asking be enough?

So, NotMuffy, how's about ...we meet somewhere in between, and you do the tests.

Sure! We'll just load up all the stuff in the Muffenstein pick-up <snip> and I'll see you in the aforementioned Nebraska!

I have never been to Nebraska. My youngest sister spent a lot of time in Nebraska when she was a toddler. My brother and I thought it was great fun to put her in Nebraska and push her around the house. My mother put an end to that when she need to put the dirty clothes in Nebraska so could do laundry. That's what she said at the time, anyway. Years later, I realized she may have been using that as an excuse. It is possible she wanted to put an end to the game when my brother and I got a bunch of blankets, got them padded up around my sister, and were preparing to push her down the stairs.

[NotMuffy]

Your sleep architecture on both sleep studies appear to be heavily influenced by medication effect. Do you have a medication list and a timeline of everything back to the first sleep study?

MSD and my neurologist both concluded that drug effect was not an issue.

Your sleep architecture shows 75% of your REM periods missing with severely prolonged REM Latency:





About the only way you can do that trick is with REM-suppressant medications (like SSRIs).

OTOH, I suppose it depends what your definition of "issue" is.

Yes, I do have a medication list and timeline from back when both studies were done. I will post it if that would be helpful to you.

Can't hurt. I think that's the next logical place to search for an explanation.