Sierra

If they set the machine at 4 cm min and 5 cm max, then it can't raise pressure above 5 cm. The machine can't go below 4 cm, and shouldn't raise pressure unless it sees obstructive apnea, hypopnea, flow limitations or snoring. The hope would be that this is high enough to control the OA without causing more CA events. Have your AHI numbers continued to decline with your fixed pressure of 5 cm?

Yes it could be your chest movement due to a strong heartbeat. I suspect the machine has more difficulty at low pressure maintaining a constant pressure. At higher pressures there is the stored energy effect of a compressed gas that potentially makes the machine more responsive, at least in the more flow, more pressure, direction.

Some things to consider. The sleep technician is going to spend some time with you to fit you with the best type of mask for you, and ensure it fits you well without leaks. The test is normally started with the lowest pressure, and then over the night it is increased to find out at what point your hypopnea is normalized. My expectation would be that you will not go to very high pressure as you are not experiencing full apnea, but there is nothing real predictable about CPAP so you never know for sure. And as far as the suffocating feeling, you are more likely to find it easier to breathe with the low to intermediate pressures. I consider the pressure my friend! They need you to be asleep to monitor apnea events, so the pressure is going to be increased when you are asleep and you are very unlikely to notice it, unless you wake up. I presume then, they will back pressure down and wait for you to go to sleep again.

I find the main issue with wearing a CPAP is the comfort factor of having to find a place on the pillow where the mask is not going to be dislodged, and a location for the hose that is not in your way, and you are not sleeping on top of it. You have to be able to change sleeping positions with some ease. And, of course they know all that, so they will help you get that sorted out.

I would focus on just relaxing and getting as good a sleep as possible under the circumstances.

1) Is there any way to know if these hypopneas are central or obstructive, since the report does not tell about it? The doctor was fairly confident that these are obstructive in nature , since I don't have underlying conditions for a central.

One would have to look at the breath by breath flow charts to see what is happening. In my experience looking at results on SleepyHead a hypopnea can be either central or obstructive. If you are getting a waxing and waning of breathing depth in a smooth cycle that does end in a full apnea, then that would suggest a central event. And I would think during the sleep test they would monitor not only the flow but your effort to breathe. Central apnea is basically a reduction in effort to breathe. Perhaps the doctor has looked at that when making the opinion.

They should be able to tell during the titration test though. If increasing pressure does not resolve the hypopnea then that suggests they are central in nature.

2) What to expect during a CPAP titration test , since I am quite apprehensive about it?

If you had an in lab sleep test it should be very similar to that. They will just increase the pressure over the night and find out what is required to resolve your hypopnea. They will also be checking for any indication that increasing pressure causes central apnea events.

3) What kind of CPAP device will be best suited for my condition ?

If pressure resolves your hypopnea, then the two obvious choices would be a fixed pressure CPAP, or an APAP. I push as much as you can for an APAP that saves detailed data to the SD card. You don't want to get stuck with a fixed pressure "brick" that gives you no data to monitory your results. I would push for the ResMed AirSense 10 AutoSet.

Now if the pressure does not resolve your hypopnea because it is central in nature, then an APAP may not work that well. The other choices would be a BiLevel machine or ASV. Probably a bit premature to be considering them at this point though.

Sounds good. I would try to convince them to set it up with no EPR, 4 cm minimum and 5 cm maximum pressure, and see what that does. And make sure they don't pull the SD card out of it on you too. I believe every machine comes with one, and it is only "missing" when they pull it out. With this machine you should be able to see what is happening during the night, what type of events you are having, and what impact pressure has on the frequency of event. I have to admit I am a bit skeptical based on what you have said so far that an APAP or CPAP is going to solve your central apnea issues, if that is what it turns out to be. That said the AutoSet will at least let you and them gather the data they need to figure out what to do next if it doesn't work.

I did a little more research on the different tapes that 3M makes. From what I can gather the blue Nexcare Sensitive Skin tape sometimes called Kind Removal Silicone tape may be easier on your skin when you remove it. It uses a different adhesive than the while paper tape. I have not tried it, so can't say if it is sticky enough to keep your mouth closed. May be worth a try if you can find it.

Nexcare Sensitive Skin Tape

SleepyHead should quickly tell you if you have a serious problem with the machine or not. Historical data should be stored on your SD card that you can go back to and determine when things changed (if they changed).

If the more detailed sleep report is not enabled on your machine, you can do that by going into the Clinical Menu. Just hold the Home key and round set button down together for 5 seconds. This will bring up the Clinical Menu. It works much like the standard menu. Go into settings and scroll down to the Options section and to the Essentials item. Push it to select the options. Change the selection from On to Plus. Then use the Home key to back out to the User Menu. That should give you a more detailed sleep report including your leak rate, over the interval you select.

Here are the links for SleepyHead.

SleepyHead Download

SleepyHead Basic Manual

This was my response to your post in another thread on the aerophagia issue.

"I have not suffered from this air swallowing thing which is referred to as aerophagia. This link on the causes and possible resolution may be of help.

Aerophgia Causes and Resolution

The issue of letting air escape out of my mouth is one I do suffer from. The best resolution I have found is to use mouth taping. I tried a couple of full face masks, but found I was mouth breathing and would wake up with a sore throat. So I have gone back to a nasal mask and tape. It is not as awful as it sounds. Here is a link to a video on the technique. I am not sure if it would help the aerophagia or not.

How to Mouth Tape for a Better Sleep"

Mouth Taping with the nasal mask may be worth a try. I found I needed to use a chin strap as well as mouth taping to keep my mouth closed. I don't know if it would stop the air swallowing or not though, as I said, I have not had that issue. I use the Nexcare 1" gentle paper tape from 3M.

As far as getting the best out of your ASV machine, have you considered using SleepyHead? If you have a PC or a Mac and a SD card reader you can transfer the detailed data to your computer and view the results over time. It gives you a very detailed picture of what is happening overnight. I certainly would be interested in seeing the results you are getting with the ASV. At one point I was thinking an ASV was in my future to control central apnea. However, for now I seem to be able to get my AHI down to the 2-3 range with the AirSense 10 AutoSet machine.

I have not suffered from this air swallowing thing which is referred to as aerophagia. This link on the causes and possible resolution may be of help.

Aerophgia Causes and Resolution

The issue of letting air escape out of my mouth is one I do suffer from. The best resolution I have found is to use mouth taping. I tried a couple of full face masks, but found I was mouth breathing and would wake up with a sore throat. So I have gone back to a nasal mask and tape. It is not as awful as it sounds. Here is a link to a video on the technique. I am not sure if it would help the aerophagia or not.

How to Mouth Tape for a Better Sleep

I'm from Canada and don't fully understand how the doctor, sleep doctor, DME provider system works. I do know from forums that others do get full Auto data capable machines out of the DME. Your main problem right now is that the CPAP has potentially made your apnea worse, not better, and you have no access to the data to figure out what is going on. Seems like that is a pretty good argument to get a better machine. Perhaps you have to go back to your medical doctor for help/support. If you can establish that your apnea is all central, then make sure to follow the other potential causes, such as medications which may be causing it, or heart and lung issues.