(06-04-2014, 02:52 PM)ShelaghDB Wrote:
So to do a Titration when you don't know where to begin for someone, is done, how?
I think the idea is that you gather the oximeter data at the same time that you're titrating on the AutoSet. SleepyHead can import the data from both devices.
Where to start? For simplicity I wouldn't really bother with the oximeter right now. It's another piece of equipment to buy and use.
If hubby is willing to try PAP and you can get your hands on an AutoSet (or a PR System One AUTO), then here's how you can start doing the titration:
Start with the machine pretty wide open, but with the min pressure high enough to be comfortable for hubby. I'd suggest setting that min pressure at 5 or 6 since he had no trouble falling asleep at 5 cm with the mask in the lab. Leave the top pressure open for the first week or so.
Look at the data everyday. The major thing you're looking for is whether or not you see the same kind of trend that is apparent in the sleep lab's data: If hubby's AHI goes UP when the pressure is above 9 or 10 cm, then you know there's some kind of problem using higher pressure settings. If hubby's AHI does NOT go up when the pressure is above 9, you'll know that the night in the lab was some kind of freaky outlier.
After a week or so you want to look at the following data pretty carefully:
The median and 95% pressure levels.
The median and 95% leak numbers.
Also look at the graphs for each of the seven days.
If his AHI does NOT seem to get worse when the pressure is at or above 9cm, then you can pretty much conclude that his pressure needs are probably pretty close to that 95% pressure setting. And you can then reset the min pressure setting to be about 1-2 cm below that 95% pressure setting and the max setting to be about 1-2 cm above that pressure setting. And run the machine with the new settings for a week or two. If the AHI by the end of that time is pretty consistently well below 5 and hubby is feeling better, you know you've found a good setting.
The sticky thing is: What to do if the AutoSet numbers look like the in-lab titration numbers?
In other words, the hard thing you might face is what to do if hubby's AHI remains high after a week of autotitration? Or what if hubby starts having significant numbers of events everytime the S9 raises the pressure above 9 or 10 cm? And that's another whole can of worms. If that happens, then you're basically back to square one and you need to consult with a sleep doc. And if hubby's untreated OSA really is mild, but PAP therapy is triggering enough additional (presumably central)
events to push him into the moderate sleep apnea category, then hubby may very well be better off doing the serious work to lose the necessary weight and keep it off. And be retested without
a PAP about six months after he's taken the weight off and kept it off to see if the weight loss was really all he needed to do.
Quote:And once you determine the area of pressure that is right for him......you then bring an oximeter into it?
Ive not been told that myself by anyone else yet so I am at present not even sure what that means.......how much it costs OR, what makes that, make this S9 AutoSet a complete sleep study, whereas without this oximeter, it doesn't?
No. Adding the oximeter to the AutoSet does NOT make using an AutoSet "a complete" sleep study. But it does give additional information about whether the person is continuing to have significant O2 desaturations while sleeping. And on an in-lab sleep test, that O2 data is used to help score real hypopneas, which require more than just a decrease in airflow that lasts 10 seconds. There either needs to be an associate O2 drop or an EEG arousal for a hypopnea to be scored on a sleep test. To have a full sleep study, there has to be ways to track the following data:
- Effort to breath. During an in-lab sleep test, that's what the belts are for. While the S9 can use its FOT algorithm as a proxy for determining the difference between CAs and OAs, it is important to remember that it is a proxy algorithm. From what I've been able to learn, the S9 FOT CA/OA detection algorithm is reasonably decent in the sense that if an event is scored as a CA, it probably was a real central apnea. But if a person is having a lot of real central apneas, then some of those apneas are likely to be mis-scored as OAs or Hs by the S9's Auto algorithm. And since hubby's AHI increased rather than decreased when he was put on PAP, you have to be at least a bit concerned that he may be sensitive to pressure and have problems with pressure induced centrals. And you can't rely totally on the S9 to tell you that the additional events are Central Apneas or Central Hypopneas.
- EEG data and muscle movement detection around eyes and jaw. This data is used to determine when the patient is asleep and when the patient is awake. This data also is critical for determining the sleep stage. And microarousals. It looks like hubby's titration study used Rule 4B for scoring the hypopneas; that means that an O2 desat was NOT required for a hypopnea to be scored; an associated EEG arousal was all that was needed. Now, as long as hubby sleeps reasonably well with mask, you can kind of assume that he's asleep most of the time the machine is on. Hence you can assume that most of the events are indeed real. But you can't determine when he's in REM vs non-REM and you have no way to measure arousals that are not related to respiratory events picked up by the AutoSet.
Quote:So I will assume no one is able to make out IF he has sleep apnea or not? LOL
You need to request the copy of the diagnostic sleep study. The titration study is not the same thing.
And here's the thing: The AHI = 5 is in some sense an artificial line drawn in the sand to determine which patients get diagnosed and which don't. But for people right near the border? Some nights their untreated AHI may be as high as 6 or 7 and some nights their untreated AHI may be as low as 3 or 4. It's not uncommon for the AHI to fluctuate a bit from day to day. And so whether they wind up with an official diagnosis after the first test may depend (strongly) on what night the test was done.
To draw an analogy: OSA is kind of like high blood pressure. Some people clearly have high blood pressure because their (untreated) readings are ALWAYS high. Some people clearly don't have high blood pressure because their blood pressures are NEVER high. And some people are in the middle with "borderline" high blood pressure problems---sometimes it's a bit too high and sometimes it's just below the "cut-off" for high blood pressure. And whether to treat a particular individual who has "borderline" high blood pressure is ultimately a decision that is made on an individual basis.
The same thing is true for folks who are on the borderline of an OSA diagnosis; the decision whether to treat or not treat is not as simple as you might expect, and it needs to be tailored to the particular borderline OSA patient's full medical history: If the person has symptoms, then many docs and insurance companies will be willing to let the person try PAP if they want to. If the person is NOT symptomatic, though, the docs are not as likely to push the person into PAP as you might think. And the rationale for not pushing PAP onto a borderline OSA patient who has no symptoms is not silly: PAP can be highly disruptive of some patient's sleep, is a rather expensive therapy to pursue, and for people with very mild OSA
and no daytime symptoms
there are no scientific studies that show any real medical benefit to using PAP.
But there ARE studies that show that if a person with very mild sleep apnea has daytime symptoms
, then PAP will do a good job of reducing or eliminating the daytime symptoms---if a quality titration can be done and appropriate pressure level can be determined. And ultimately that's why many sleep docs leave the choice of whether to PAP up to the patient when the patient has been diagnosed with borderline OSA.
Quote:In any event he does not have an AutoSet.
So a self-titration (for now) is kind of a moot point?