Apnea events vs SP02(%); does this sound reasonable?

[AMUW]

Last night's ResScan graphs. Settings: Epr OFF; Auto mode w/pressures 8-12. AHI 2.9. Observation: Better control. Clusters less severe. Pressure bumping max in an apparent effort to curtail clusters but max pressure is apparently inadequate to do the job. Some interruption of sleep due to pressure increases causing slight leaks. Plan to try same setting for a couple more nights before increasing pressure to maybe 9-13. I'll report back after a few days.

Congrats on the better results, I hope they stay that way.
From looking at your Autoset pressure curve, I see no need to bump Pmax upward. It would be different it P kept hugging the max level for extended time. Note how quickly ResMed raises the pressure, trying to beat apneas to the punch. Then, with no apnea, the pressure decreases asymptotically to Pmin ... until another event is sensed. Also note that after sleep onset your P level pretty much hugged the lower limit.
So was it mainly reducing EPR that helped? I've never played with this parameter. What have we learned? If you look at your past flow cessations in greater resolution, were they happening during the inspiratory (flow curve positive) or expiratory (flow curve negative) phase?
My own current flow curves look somewhat better than what you just showed... in that the anomalies show up only a few times during the night, at a lower amplitude and shorter duration, AHI in the 1-5 range. But they still seem to cause enough sleep fragmentation to affect my total subjective quality of sleep. And I'd be back with the clusters if I stopped the nasal decongestants and / or slept on my back; probably a different cause than in your case, but I suspect the same upper airway instability effect.

P.S. you didn't address my qn on humidifier parameters possibly having an effect. Is your Eastern NC sleeping environment rather warm and humid nowadays?

[jonnybee]

Last night's ResScan graphs. Settings: Epr OFF; Auto mode w/pressures 8-12. AHI 2.9. Observation: Better control. Clusters less severe. Pressure bumping max in an apparent effort to curtail clusters but max pressure is apparently inadequate to do the job. Some interruption of sleep due to pressure increases causing slight leaks. Plan to try same setting for a couple more nights before increasing pressure to maybe 9-13. I'll report back after a few days.

If you look at your past flow cessations in greater resolution, were they happening during the inspiratory (flow curve positive) or expiratory (flow curve negative) phase?
snip...........
P.S. you didn't address my qn on humidifier parameters possibly having an effect. Is your Eastern NC sleeping environment rather warm and humid nowadays?

Here is a graph from three nights ago prior to increasing pressure. Maybe you can glean something from it.

As for the humidity, it is warm and humid here in NC now so I ceased using the humidifier a couple of weeks ago.

[Slartybartfast]

Well, what jumps out at me and bites me on the nose is this:

Note that at the event markers correspond with periods where there's no breathing going on. You still have alternating periods of rapid, deep breathing (gasping) alternating with periods of very little breathing (choking). You're alternately choking and gasping. And your Minute Variation trace confirms that's what's happening. Your airway is collapsing, then you're likely waking and gasping, only to have the airway close again. Cycle repeats. That indicates your pressure is too low.

Zoom in to 1 minute scale on your flow graph and let's see the shape of your breath peaks. I'd bet money they are not triangular as they should be if you are sleeping, but likely rounded during your gasping, then becoming more triangular at the end of the gasping period, then flat-lining.

[jonnybee]

Well, what jumps out at me and bites me on the nose is this:

Note that at the event markers correspond with periods where there's no breathing going on. You still have alternating periods of rapid, deep breathing (gasping) alternating with periods of very little breathing (choking). You're alternately choking and gasping. And your Minute Variation trace confirms that's what's happening. Your airway is collapsing, then you're likely waking and gasping, only to have the airway close again. Cycle repeats. That indicates your pressure is too low.

Zoom in to 1 minute scale on your flow graph and let's see the shape of your breath peaks. I'd bet money they are not triangular as they should be if you are sleeping, but likely rounded during your gasping, then becoming more triangular at the end of the gasping period, then flat-lining.

Looks like you hit the nail on the head.

[AMUW]

You may not like three arm chair semi-techs see different things in your data ... but take the best insight for your benefit from the discussion.
Now that you zoomed in to see individual breath cycles, they DO NOT show what Slartybartfast and I were expecting, namely chopped off peaks to indicate flow restriction; neither did you show us any Flow Limitations occurring.
In the small window seen you have a 16 sec obstructive apnea rolling right into an 11 sec apnea ... to me effectively a 27 second flow interruption. And if you now selected a 5 minute detailed window, you'd see no ventilation then hyperventilation at 18 BPM repeating maybe 3 times. It remains to explain what causes them, and why they went away sooner last night vs. the night before.
I may not be seeing the full picture, but I suspect that during these cluster periods Autoset has already driven up the pressure above the minimum. You may be able to see from your curves what it is that precedes and triggers the compensatory pressure rise, even before an apnea is "chalked up": if not a flow limitation or a leak, then is it the first flow restriction?
BTW, on your 1 min range, and during zero flow, can you see the small oscillations ResScan uses to measure airway resistance, i.e. the Forced Oscillation Technique results? you can enhance the vertical scale by dragging up on the left numbers.
Regarding your current hot & humid environment: could it be that your upper airway is reacting to "sauna-like" air? in which case you could plug in the climate control for a cooling pass over the water tub, which reduces the air humidity content.

[jonnybee]

Please remember that the last graph was from three nights ago before I increased the pressure when I was at my worst.

Below are the graphs from last night. I slept soundly for seven hours and I feel noticeably better today. I think we found the right pressure setting. I fully realize that I can still expect bad days but it looks like, with the help of all that contributed, that we have hit on a combination of pressures that are very close to optimum. I plan to leave everything as is for a few days and see if the results remain good. Again, I really appreciate time and effort spent by all that contributed in order to help me nail this thing down. This is another example of a lab titration unreliable. Not really blaming the lab itself; just pointing out that the conditions under which the lab conducts the tests are totally artificial and are more likely to be inaccurate than not. In my case, the lab titration was off by a good 5cm.

Take care all.

[greg-g]

Its really good to see your getting on top of your settings, It shows the power of understanding and making your own adjustments.
We all learn from these discussions.
I haven't changed my settings for months, but I'm continually amazed by the nightly variations in pressures and events.
I think there was a brief mention somewhere, but you can change the graph ranges to better display your own data by adjusting the values in the
Tools / Options / Preferences menu Graph settings.
I use a pressure setting scale for instance of 6 - 15 rather than the default 0 - 25

[Pugsy]

Looking good on that last report especially since you are reporting feeling better.

The whole idea is to limit the events and flow limitations so that you can feel better. It doesn't really matter when they occur or what causes them. They are all treated the same. They need to be prevented. You know the biggest change was turning EPR off. Funny how that made such a remarkable difference. I think that since EPR reduced overall pressure during exhale (which is roughly 50 percent of the night) by 3 cm that it just allowed more events to slip by the defenses. This sometimes happens with EPR and sometimes no difference at all.
Then the tiny increase in minimum helped even more.

I may be a bit over simplistic in my thinking but I don't see the need to dissect every breath in minute detail unless there are significant problems that are going unresolved. Or maybe you just like looking at the teeny tiny minute details, that is okay too.

The whole goal is to prevent the majority of events and while doing so allow you to sleep well and get some restful restorative sleep. Yes, we will all have some bad nights on occasion. Given your new understanding of how things are trending and what to look for and how you feel, then yes, give this a bit more time to see how it settles in.

My only concern is if the pressure variations (which may even settle down a bit now) mess with your sleep. Only you can judge that but now you know how to try to work that out also if it becomes a problem.

I think you now have a good handle on things, new confidence and now know what to look for. Does it hurt to have 3 cooks in this kitchen? Not really. All of us were wanting the same thing for you and pretty much basic suggestions were given, we just might have a little different explanation for some of the things we see on the reports. Extra caution never hurts.
I look at general patterns and don't delve into the minute breath by breath stuff because I figure it all has to be treated anyway. Now if weird stuff going on or problems seem to be unable to be resolved, different story. I figure take the easy way first and not make it difficult unless a reason warrants it. Just my own way of doing things. Everyone has their own way of looking at things and doing things.

Keep us posted on how you feel.

[Slartybartfast]

Looks like you hit the nail on the head.

My kids keep saying that I'm smarter than I look. I wonder what they mean by that . . .

There we have what 'cha call a respiratory-related arousal, or RRA. Your airway is closing up, you're choking, and to keep from dying in your sleep, your brain kicks you awake and you start breathing. You may not remember awakening, but you are doing so. Those round-topped flow peaks are indicative of an awakening. Watch what happens as you scan that flow trace to the right, and you'll see those rounded peaks shrink and slowly morph into a sawtooth shape, whch happens when you resume sleeping. Then you'll have another obstructive apnea and you'll get kicked awake again. It's very hard to get any rest when you're constantly being awakened like that. And that's why so many people complain of not getting restful sleep.

[Pugsy]

My kids keep saying that I'm smarter than I look. I wonder what they mean by that . . .

I saw that graph and your previous comments and was going to ask you what brand of crystal ball you were using because I wanted one. Good call.

[Lizistired]

Wow, big improvement. I bet you feel better!
I want your leak line!
Here is the link to Dreamdivers Rescan tutorial, if you haven't seen it. Lots of good tips for making the viewing easier.
http://montfordhouse.com/cpap/resscan_tutorial/

BTW, I finally used the LT last night. Huge difference over the FX! I got to sleep with my big pillow and even slept on my stomach! I made a top clip for it and really like having the hose over my head and out of the way. Thanks a bunch!

[Slartybartfast]

Aw shucks!

That's the power we have when we have access to a fully data capable machine AND have the software to analyze what's going on. I think software should be included with the machine.

My sleep doc said, when I showed him my data last time, "With all this data, you could just about do a sleep study yourself. It has most of the capability of what we do here in the lab." He was remarking on all the features of the software. I don't think he had ever seen it before, though he prescribes S9 Elites all the time. He relies on data from the lab and it appeared he had no idea Resmed had software available. And his techs do the compliance monitoring.

I only wish that the vendors would take a hard look at what a motivated patient can do with their software and perhaps offer regional training classes, or perhaps webinars or videos that can be downloaded from the internet that go beyond simply setting up and using the software. (ARE YOU LISTENING DEVILBISS?) It seems to me a lot of people are missing out on understanding what is going on. And it's not rocket surgery, as you can see. It's just a matter of looking into the data.

Glad you're FEELING better. Reducing the obstructive apneas means reducing your RRAs, which means you're sleeping more efficiently.

That said, it IS puzzling that you don't show any evidence of flow limitation. Seems your airway just slams shut and has to be opened by waking. Of course, raising the pressure will eventually keep it open, but , at least in my case, I can see when I'm on the edge of not having enough pressure because my flow peaks will flat-top which ResScan picks up on and shows in the form of the Flow Limitation chart.

[jonnybee]

Thanks to all again!!! I can't tell you just how much better I feel today after almost seven uninterrupted hours of restful sleep.

Liz, hope you can use the LT. That's what I use in conjunction with one of the Puresom ruby chin straps and tape. Sounds overkill, but it holds my chin up and seals my lips. BTW, I wear the chin strap a little more forward so that it pulls more upward. I find that works better for me. Wearing it forward causes the bottom straps to fit over my ears but that is not bothersome for me. I've tried most everything and this combo works best for me as shown on the leak line.

Take care everyone.

John

[AMUW]

jonnybee, congratulations again. This time your curves look like my good nights. If I may bring back my analogy:

Dynamic stability interpretation: to me the repeating apneas felt like a race car going over very rough repeating bumps and turns (like they show SFO hill chases in the movies), or a helicopter sustaining damage to a blade, or a skier not knowing how to negotiate the moguls... taking a long time to compensate. And the cumulative arousals and sleep fragmentation led to daytime sleepiness.

Your system has now found the compensatory trick: like a new car suspension system, or special mogul skis with different vibration and damping characteristics.
I still have relapses, am not yet where I'd like to be.
In the end may I suggest that -- for later reference and before you forget -- you make a careful list of the conditions and changes which caused the worsening in the first place, and the resolution thereafter: therapeutic settings, environmental factors, related bodily functions. I heard you mention Autoset pressure range, EPR (I find eliminating the 3 cmH2O relief quite uncomfortable), chinstraps (I have learned to sleep on my side with head up).

Re the value of zooming in on the detail: if EPR was the critical change, then you should be able to confirm in your past flow curves (maybe at 5 min time scale resolution) that the apnea starts during the expiratory phase of your breath. My neurologist - sleep doctor has a theory about the interaction between O2 - CO2 exchange linked to neural control of the breathing muscles and nasal reaction ... including timing (phase) differences during a breath cycle.

Finally, I see in your flow curves maybe a 10 minute long sleep onset duration. Have you tried eliminating the initial ramp?

[Slartybartfast]

Hey John,

Now that you've taken the cure, not to get too personal or anything, but how are your nighttime urinary habits?

Reason I ask is that most of us guys need to relive ourselves at least once/night, and once you're on CPAP, your more efficient sleeping usually causes the heart to lower its output of ANP (atrial natriuretic peptide) http://en.wikipedia.org/wiki/Atrial_natriuretic_peptide which causes the kidneys to dump sodium to the urine, requiring more frequent urination. Usually, starting on CPAP reduces ANP levels, and the need for nighttime urination.

I've managed to get two friends to try CPAP again, after giving up on it years ago, by mentioning that factoid to them. One of them said, after about a week on the hose, that that benefit alone was worth the price of admission.

Here's a better explanation:

From “Ask the Doctor” column of American Sleep Apnea Association Newsletter:

Why does sleep apnea sometimes lead to frequent urination at night?
Nocturia, or nocturnal urination, is sometimes a symptom of sleep apnea. In fact, nocturia in younger adults-who are less likely to have other medical causes of nocturia-is a strong indicator of sleep apnea. While the precise relationship has not been thoroughly studied, it appears that the most likely reason patients with untreated sleep apnea have more frequent urination at night is related to the increased pressure in the right side of the heart. This increased pressure is usually the result of low oxygen levels in the bloodstream caused by the apnea events: when oxygen levels fall, the heart works harder to get oxygen to the brain.

An increased pressure in the heart is a sign that there is too much liquid in the body: when the heart receives the stimulus of the increased pressure, higher levels of a hormone called atrial natriuretic peptide (ANP) are secreted from the heart. ANP is a diuretic that is associated with the increased need to urinate.

When sleep apnea is effectively treated, nighttime urination can be dramatically reduced. Studies have shown that ANP levels in patients with untreated sleep apnea are increased and levels reduced in patients using CPAP effectively. Remember, not all causes of frequent urination are related to untreated sleep apnea; prostrate problems, for example, may cause increased need for urination. Discuss any concerns you may have with your doctor. Dr. Patrick Strollo, Jr., MD is the Medical Director of the Pulmonary Sleep Evaluation Laboratory at the University of Pittsburgh Medical School. August-September 1996 from: http://www.ecomagic.org/apnea/NoctThyroidAllergies.html