No events with at-home titration.Why does pressure increase?

I have to wait another five weeks to see my doctor and I'm a bit confused. I know there's a lot of knowledgeable people here so I figured I'd try and post this while I'm waiting.

I've had debilitating fatigue for many years now and recently suspected maybe I had SA. So I got an at-home test done and it came back negative (barely slept that night) and the doctor told me I don't have SA according to the results. But because of my symptoms he said maybe I have UARS and sent me to do a titration. The sleep clinic I went to doesn't do in-lab titrations (seemed odd to me) and they sent me home with an S9 Autoset to sleep one night with and log data (which doesn't seem to be the method usually used to find UARS... don't know how useful that is).

I've done my own research and therefore knew about Sleepyhead and therefore imported the data before I sent the machine back. I slept really poorly again, but the machine's data seems to support that I don't have SA. Got 0.00 score for AHI and RDI. But the pressure still went up while I slept (min. was at 4.0). It seems like every time I nodded off, the pressure would increase to around 10 and wake me. But why would the pressure go up if I wasn't having any events? I read that flow limitation is sometimes looked at to determine UARS but am not sure about that. Can anyone make anything of my data?

Screenshot:
http://i.imgur.com/TqRMzDA.png

jdip wrote: But why would the pressure go up if I wasn't having any events? I read that flow limitation is sometimes looked at to determine UARS but am not sure about that. Can anyone make anything of my data?

Screenshot:
http://i.imgur.com/TqRMzDA.png

flow limitations and snoring drive up the pressure fastest on an autoset, the pressure comes up, you stop having the flow limitations, and the pressure goes back down again, and you get flow limits again, and the pressure goes up.

higher minimum pressure would stop the roller coaster effect.

palerider wrote: flow limitations and snoring drive up the pressure fastest on an autoset, the pressure comes up, you stop having the flow limitations, and the pressure goes back down again, and you get flow limits again, and the pressure goes up.

higher minimum pressure would stop the roller coaster effect.

That makes sense.

If someone didn't have any breathing issues, do you think the machine would just stay at the minimum pressure of 4?

jdip wrote:If someone didn't have any breathing issues, do you think the machine would just stay at the minimum pressure of 4?

Pretty much the pressure stays the same if there is nothing to drive the pressure up.

jdip wrote:

palerider wrote: flow limitations and snoring drive up the pressure fastest on an autoset, the pressure comes up, you stop having the flow limitations, and the pressure goes back down again, and you get flow limits again, and the pressure goes up.

higher minimum pressure would stop the roller coaster effect.

That makes sense.

If someone didn't have any breathing issues, do you think the machine would just stay at the minimum pressure of 4?

The machine has been programmed to think of flow limitations and snoring as breathing issues that warrant a pressure increase.

The rationale: Flow limitations can indicate the airway is partially obstructed and in danger of collapsing in the immediate future. Snoring can indicate the airway is in danger of collapsing AND snoring can create arousals all by itself. Since both flow limitations and snoring can often be "improved" by increasing the pressure, the machine is programmed to increase the pressure, and hence lower the risk that the airway will actually collapse.

In theory, it's great. In practice? Well for many people, ironing out the flow limitations and eliminating the snoring by increasing the pressure works well---they sleep as well or better with the flow limitations and snoring eliminated and the pressure increases don't disturb their sleep. For other people, it's more problematic. Sometimes the pressure increases are more disruptive than the flow limitations and snoring. Sometimes the person's flow limitations are induced by some other anomaly in their respiratory system than a partially collapsed airway, and they never really "even" out no matter how much the machine increases the pressure.

jdip wrote:If someone didn't have any breathing issues, do you think the machine would just stay at the minimum pressure of 4?

yes. as the lady said, better than I could, if there's no snores, flow limitations, apneas or hypopneas, the pressure won't increase. (I'm only responding because it was my comment you responded to )

Thank you all for sharing your thoughts and knowledge. I'm anxious to see what my doctor will say. I'm kind of hoping that I do have UARS or something, so that I can finally know why I feel so tired and do something about it.

Remember also that if the machine increases the pressure as it senses the need...it is doing its job which is "prevention" and what you don't see are any number of airway collapses that were prevented from ever happening.
We don't get a number for the prevented events...we only get a number/flag when the event slips past the defenses and isn't prevented.

My AHI might be 0.5 for last night...but that only tells me what wasn't prevented. I have no clue as to how many airway collapses were prevented.

jdip wrote: I'm kind of hoping that I do have UARS or something, so that I can finally know why I feel so tired and do something about it.

Is it safe to assume you have had thorough workups looking for other issues?

jdip wrote:Thank you all for sharing your thoughts and knowledge. I'm anxious to see what my doctor will say. I'm kind of hoping that I do have UARS or something, so that I can finally know why I feel so tired and do something about it.

Sometimes, you may not get a clear diagnosis, but CPAP still helps. That tends to throw a monkey wrench into the insurance process, though.

Pugsy wrote:Remember also that if the machine increases the pressure as it senses the need...it is doing its job which is "prevention" and what you don't see are any number of airway collapses that were prevented from ever happening.
We don't get a number for the prevented events...we only get a number/flag when the event slips past the defenses and isn't prevented.

My AHI might be 0.5 for last night...but that only tells me what wasn't prevented. I have no clue as to how many airway collapses were prevented.

What you said makes total sense.

ChicagoGranny wrote: Is it safe to assume you have had thorough workups looking for other issues?

Yep... have seen many doctors over the years and done a lot of bloodwork. That's why I'm desperately hoping that it's SA/UARS so that I can finally know what's wrong with me after all of this time.

archangle wrote: Sometimes, you may not get a clear diagnosis, but CPAP still helps. That tends to throw a monkey wrench into the insurance process, though.

Right. I know a lot of insurance companies don't cover UARS because it's still kind of obscure. But in any case, I don't have insurance at the moment so I would be paying out of pocket anyway.

I have fibromyalgia, or chronic fatigue syndrome.. diagnosed long before the SA...no blood or other lab work, no x-rays, etc. needed for the diagnosis. A rheumatologist figured it out in 5 minutes with a very simple hands-on test. I'm still fatigued from that, but with cpap I am finally able to sleep at night, which vastly improved my state of mind, and I'm much happier now because of it. Has any medical professional mentioned fibromyalgia to you?

library lady wrote:I have fibromyalgia, or chronic fatigue syndrome.. diagnosed long before the SA...no blood or other lab work, no x-rays, etc. needed for the diagnosis. A rheumatologist figured it out in 5 minutes with a very simple hands-on test. I'm still fatigued from that, but with cpap I am finally able to sleep at night, which vastly improved my state of mind, and I'm much happier now because of it. Has any medical professional mentioned fibromyalgia to you?

Sorry to hear that you have fibromyalgia and CFS, that sounds very difficult. I'm glad that CPAP is helping you. You said you are still fatigued but has it diminished at least a little bit? From what I know about fibromyalgia, one of the main symptoms is chronic pain, which I do not have and no doctor has brought it up. As for CFS, I'm still investigating avenues (such as SA and UARS), but if the doctors can't figure out what's wrong with me then I guess I may end up with that diagnosis, as I understand it is an exclusionary (of other diseases) diagnosis.

Update:
I finally saw my doctor yesterday and he told me to do a two month trial on a CPAP machine. He said that the titration didn't tell him anything in terms of "diagnosis", but just gave him the pressure that I would need to use (9 cm H2O). It's clear that I don't have sleep apnea, but may still have UARS, which I haven't been tested specifically for. The doc seems to think that it would be easier for me to do the CPAP trial than to wait for a more advanced sleep test to test for UARS. Which I find kind of weird as an approach... but I guess makes some sense because that test would take many months of waiting for (unless I did it with a private establishment, where I'd have to pay $1500 out of pocket).

So I've been calling a bunch of equipment providers today and wow, this stuff is crazy expensive in Canada, even to just rent. I don't have insurance and it seems like it would make a lot of sense financially to get a used machine. What do you guys think of going this route?

jdip wrote:this stuff is crazy expensive in Canada, even to just rent. I don't have insurance and it seems like it would make a lot of sense financially to get a used machine.

These people will ship to Canada - http://www.secondwindcpap.com/

Check out their gently used and new opened box models. I prefer ResMed S9 Autoset.

Make sure you get one of the experts here to give you the lowdown on a machine before you order it. You definitely need to be careful and under no circumstances order a "brick".