transitional sleep apnea

Hi. The problem is nobody has heard about sleep onset apnea . It is not the characteristic obstructive sleep apnea. On doing research I have learnt Tha such an apnea can be central and not obstructive. Or it can be both. The gasping at the beginning of the sleep cycle leads to constant awakenings. My medical aid wont cover a cpap machine because I would have to be classified a moderate sufferer. How accurate cam these tests be. I took a sleeping pill on the night of the test and that helps you pass through the first phase of sleep when I was suppose to show where my gasping occurs. If I know for sure a cpap can help me than I will have to buy it. Would not an automatic cpap machine be better so that no ajustments would need to be made?

If you do a search here for sleep onset apnea, I suspect you will find a few threads. I recall it being discussed some time ago, but not recently until you posted. Many people post a few times but then do not come back to update. It is the nature of forums...

In the US there seems to be a progressive route that is prescribed I think mainly by medicaid and insurance companies. They like to give you a fixed pressure CPAP, and if that does not work, then an APAP, and if that does not work then a BiPAP. For the most problematic cases of central apnea an ASV machine is prescribed. My thoughts are that the only machine that has real significant treatment benefits for central apnea is the ASV. The others are pretty much the same, although certain types of BiPAP machines may behave a bit more like an ASV.

The basic treatment for central apnea is to avoid pressure. For someone that has both obstructive apnea and central apnea that is a problem, because of course obstructive apnea is corrected by pressure and centrals are aggravated by pressure. So where many end up is with a compromise pressure that is high enough to reduce obstructive, but low enough to minimize the centrals. I have a ResMed APAP machine, but I have found that I can control that compromise pressure best by setting it to fixed CPAP mode. For that reason I don't think an APAP is an obvious advantage. However it covers all bases as you can use it in either mode, and starting out in auto mode can help you find the compromise pressure sooner.

Essentially all the BiPAP does is increase the differential between inhale and exhale pressure. The CPAP and APAP are limited to 3 cm differential, but BiPAPs can go up to 10 or more. The problem is that this differential is a double edged sword. It makes the overall pressure higher, and can aggravate centrals, but at the same time it can simulate a breathing assistance effect which can reduce centrals. Certain machines can detect lack of effort to breathe and will trigger a backup cycle rate to assist breathing.

The ASV monitors every breath, and helps assist breathing on a breath by breath basis. It is the most sophisticated of them all, and often is the most effective with problematic central apnea.

This all said, you may not have central apnea at all. The normal way to measure it is in a lab sleep test. A trial APAP machine that detects central and obstructive apnea is often used as a confirmation method.

One thing to keep in mind is that when a lab sleep test is being done you are not being "treated" with pressure. They are just monitoring your breathing etc and looking for apnea and hypopnea events. The other lab test is a titration test where they do essentially put a CPAP machine on you and use pressure to determine how much you need to stop obstructive apnea without causing central apnea. Not 100% sure but I believe they can start with a higher pressure to see if that prevents sleep onset apnea.

Also it is kind of the same with a home APAP. You can start with any pressure up to your minimum set pressure. or fixed CPAP pressure. If that pressure is effective, you will not experience sleep onset apnea. And with SleepyHead you will see if there is an apnea event or not. Same with an in lab titration test. The graph below is an example of my SleepyHead report from a few nights ago. You can see each breath, with the mask pressure cycling up and down with each breath (9cm on inhale, and 6 cm on exhale), until the machine detects I am asleep, and then it ramps up to my fixed CPAP set pressure of 11 cm on inhale and exhale. There is a bit of a disturbance in flow rate just after it switches to the fixed 11 cm where the green vertical line is, but no real apnea. If there was, you would see it. An apnea is 10 seconds or more with no flow.

No, I don't have any further information. There are a lot of people coming and going on the forum. One would like to think that most stay until they have solved their issues, and then leave. However, there are probably some that don't solve their issues and still leave. I think CPAP statistics overall are not that good. From memory 30-50% abandon the treatment. Lots of unused machines sitting in closets somewhere.