(03-13-2014 07:55 AM)WakeUpTime Wrote: It's either a transitional thing (only 2 mo. of CPAP) or the "Complex" part of CSA (CSA during CPAP). [No significant CSA was detected during the sleep study; only with CPAP.]
I'm just curious how much time to give it before being convinced it's CSA. Perhaps somewhere in a 6-12 month window I suppose. I really seem to be stuck on that 5 CA events/hour number. I don't know if that's the cause of the ongoing crummy sleepless nights on CPAP. (It's not a tolerating thing.) The OSA is down to a low 2, but sleeplessness continues (awake every 1.5 hours last night).
Just how restless are you during the night? Seriously, how much WAKE time while masked up are you talking about? And are the CAs being scored during times that you know or suspect you're not fully asleep?
Wake breathing is much less regular than sleep breathing. We breath deeply for several breaths, and then take longer before the next inhalation. We momentarily hold our breath while concentrating---even on something as simple as turning over in bed. And in some people, machines will sometimes mis-score normal, but ragged wake breathing as CAs. So if many or most of the CAs are scored during times you're likely awake or drifting in and out of a very light sleep, some or all of the CAs may not be real central apneas---if you were in a lab, they would not be scored as an apnea because the EEG says you were awake when they happened.
The transition to sleep also is rougher in some individuals than others. As the CO2 sensitivity trigger for breathing is reset when responsibility for managing the breathing is handed over from the voluntary nervous system to the autonomous nervous system, it's pretty common for a "central" apnea or two to occur. On an in-lab sleep test, these sleep transition apneas are NOT scored as "real CAs" (unless they're so numerous that it's clear they're the cause of the patient not being able to get into real sleep.) So if the centrals are clustering at the points where you are dozing---going in and out of sleep, then another possibility is that they're just normal sleep transition events.
So the answer to "How long should I keep PAPing before I should be convinced that what I'm seeing really is Complex Sleep Apnea (CompSA)?" is "A few weeks after you are sleeping well
with the device, where well
means you're not reporting that the nights are restless and sleepless" As long as your sleep is badly fragmented and you're spending a lot of WAKE time breathing with the mask waiting (or fighting) to get back to sleep, the CAs are likely to be considered part of WAKE breathing or sleep transition breathing by the doc who's treating you.
For now, I'd suggest letting the sleep doc know what you are seeing, but follow his lead about prudent watching of the CAs. And focus on trying to sleep more soundly with the PAP machine. If the CAs don't once you're sleeping more soundly, then you know that there is a real possibility that the CAs are a symptom of CompSA
Quote:The machine's set at a constant 12 at the moment rather than variable, which seems to be the number that almost ends the OSA. The pressure doesn't really bother me, but my stomach each morning is sure ballooned/bloated/cramped.
The stomach would probably profit from a reduction in pressure, but then the question is how high will the obstructive events go? In the long run, you may be better off with a slightly higher AHI and a lower pressure so the stomach is happier and the sleep is more continuous.
Have you reported the aerophagia (the bloating and cramping) to your sleep doc? If not, you need to start there. If you've been dealing with serious aerophagia for two months, it's time to get the sleep doc's attention about this. Until the aerophagia is dealt with, you're not likely to sleep well with the PAP. Until you're sleeping better with the PAP, there's no way to tell if the CAs are a real problem or not.
So focus on doing what you can to minimize the aerophagia.
Standard advice for aerophagia includes:
- Do all the GERD self-help stuff---in particular, try sleeping with the head of the bed raised and don't eat too late.
- If you have Flex turned OFF, turn it on and see if that helps.
- If you have Flex turned ON, play with the settings---don't automatically assume that "more" exhalation relief equals "more" comfort. Some people find a Flex setting of 1 or 2 to be more comfortable and more natural feeling than a setting of 3.
- If you have Flex turned ON, experiment with turning Flex OFF.
- Consider prudent use of the Ramp. On the PR machines, if events start happening during the ramp up period, the machine will raise the pressure by about 1 cm and then continue ramping up to full pressure from there. By prudent use of the ramp, I mean two things:
- Set the starting ramp pressure not too far below your prescribed pressure, and set the ramp time to be reasonable---long enough for you to get to sleep, but not several times longer than it will take you to get to sleep. With a prescribed pressure of 12, I'd suggest a starting ramp pressure of around 8cm if you can tolerate it.
- Hit the ramp button whenever you wake up with your stomach feeling bloated or ballooned. The lower pressure may ease the stomach problems.
- If there's evidence of mouth breathing, the consider using a FFM or a chinstrap or both.
- Experiment with sleeping positions. Sleeping on the right side may make the aerophagia worse than sleeping on the left side---it has to do with the internal arrangement of our organs. Sleeping on your back may make the aerophagia a bit easier. Also consider your head position relative to your chest. Some people find having their chin pointed away from the chest helps prevent the swallowing; others (including me) find that it's better to have the chin pointed down towards the chest.
- Experiment with the humidifier setting and the temp setting on the hose if you use a heated hose. Too much or too little humidity may cause congestion or nasal or mouth dryness that leads to swallowing. Too much or too little heat may also cause discomfort in the sinuses or the mouth, which can lead to swallowing.
If nothing seems to help OR if the aerophagia is really severe, the make sure you call the doctor. For some people the only real solution to aerophagia is to be switched from CPAP/APAP to a bi-level machine. The EPAP on a bi-level machine can sometimes be set lower than the CPAP setting without any statistically important increase in the number of obstructive events, and hence the mean pressure needed to control the OSA can be reduced, and this in turn can lead to real relief of the aerophagia problems.