Sierra

Actually unless the leak is very large, the machine is quite capable of keeping up with the leakage flow. If you look at the blue mask pressure graph you can see it is not affected by the leaks. The problem the machine has is that it does a rapid cycle of the air flow once an event is detected, and from that it also looks at what impact that has on pressure. If it is an obstructive event then a flow cycle causes a larger pressure cycle. With an open airway or central event it does not impact pressure much at all. That is how the machine distinguishes between an obstructive event and an open airway event. Then it decides based on the type of event whether or not to increase pressure in response to the event. With an obstructive event it increase pressure to open the airway. When the airway is already open then it is of no value to increase the pressure. And since increased pressure can cause more frequent open airway events, it is actually counter productive to increase pressure. When the leakage is high, the machine apparently cannot detect the impact of flow on pressure so it simply ignores them. So you may be having events during a high leakage event, but you will not know about it. The solution of course is to solve the high leakage cause. . She tried mouth taping for a while, but does not like it. She told me that women are smart enough to learn to keep their mouth closed... I am smart enough to not contest that one! I do remind her when she is having significant events and sometimes she makes improvements by adjusting her mask. Overall her long term average of AHI is less than 0.5, so I don't think it is having a significant impact to her overall AHI. My AHI is about 0.8 and higher so I am in no position to tell her that she has to improve!

OSCAR works with ResMed machines that have an SD card, and also I believe the DreamStation and DreamStation 2. It may not work with some very basic CPAP machines that do not have auto mode or even a SD card slot. To use it, you need a PC or Mac, and a SD card reader to transfer the data from the card to your computer. And of course you need the SD card in the machine. Some clinics pull a bit of a dirty trick and remove the SD card so the machine does not capture data. I have no idea why, because when you don't capture the data on a SD card the data is lost permanently. If there is no card, then any SD card less than 32 GB should work.

My wife and I both use a CPAP and I track the results with a freeware program called OSCAR. It lets you see when there are excessive leaks and displays them as grayed out areas on the data graphs. These are times when the leak rate goes above the 24 L/min red line (at least on our ResMed machines). My understanding is that the leaks from an open mouth tend to be flat topped in shape. I mouth tape and generally do not have leaks above the red line. My wife does not mouth tape, and does have more leaks, and some of which I suspect are mouth leaks. See the graph below. Some of the leak periods have flat tops and perhaps are mouth leaks, while one other is ramping up and perhaps is the mask not sealing on the face. She uses a Brevida nasal pillow mask. You will also see there are no events recorded during the grayed out high leak periods of time.

As far as the impact on AHI, large leaks above the red line on the ResMed (and I think DreamStation is similar) suppresses the reporting of apnea events. If it is a marginal event sometimes they can be reported as unidentified events. The high leak prevents the machine from determining what type it is. But in general events get suppressed during high leaks and as a result reduces the frequency of events and AHI. You could be still having them, but they are not reported. I agree with your thoughts that your machine is likely under reporting events during large leaks.

Hope that helps some,

CPAP can take some getting used to. Getting the machine set up properly and finding a mask that works for you are the keys to success. Assuming you have a machine like the ResMed or DreamStation that captures data on a SD card, it is worthwhile downloading it and viewing it with a freeware program called OSCAR. That will let you know how well the CPAP is working for you and what adjustments may be needed.

I use a CPAP but have no TMJ issues. My wife also uses both a CPAP and a TMJ splint made by the dentist. The combination seems to work for her.

About all I can say is that you should not be seeing O2 drop significantly below 95% during sleep. Drops below that suggest apnea events which may be central or obstructive.

The issue with CPAP clinics is that most do not want to take the time to look at your detailed sleep data. Some of us look at our own data using OSCAR which is a freeware program that runs on a Mac or PC. You download the data from your CPAP SD card with a card reader. It can be very helpful in figuring out what is going on while you are sleeping, or trying to sleep. Many sleep clinics do not fine tune the CPAP settings based on the detailed data. They just set a wide range between minimum and maximum pressures and put the machine in Auto.

The other big issue with CPAPs is the mask. There are many different types and one pretty much has to try them to find the one that works best for you.

As for heartburn, I just take one or two Tums before bedtime and the issue pretty much goes away. I also attribute them to my good bone density tests.

It would be helpful to see your mask pressure chart as well. I would try setting Your minimum pressure at 8 cm, with a ramp start pressure of 8 cm also. I like to use the Ramp Time set to Auto. And set the EPR to 3 cm (that is the max) and also to Full Time. That will start you out with an IPAP of 8 cm, and EPAP of 5 cm. When the machine detects you are asleep it will switch to auto and increase pressure as needed above 8 cm.

So far I have never run into an airline that charges for bringing a CPAP on board in the cabin. They are classed as medical equipment and I believe they are obligated to allow them at no charge. You do have to open the bag and allow an inspection of them when you go through security. The later ResMed bags have convenient straps that attach them to the vertical bars on a carry on bag with wheels.

What kind of CPAP do you have? Are you using EPR (ResMed) or Flex (DreamStation)? The pressure seems to be on the low side. You might find some benefit in a higher pressure and using EPR if you are not already.

After saying that I have not had any CSR for over a year, I got a full session of it last night. No idea what may have triggered it other than it has been on the warm side for the last couple of days. But, I did get a restful sleep. The night before my AHI was 0.15, and now here I am over 3.0. Can't recall when that has happened before.

I think the advantage of the bisoprolol is that it is longer acting than the metoprolol, and only needs to be taken once a day and is said to have a more uniform effect throughout the day. I take my 2.5 mg once a day in the morning, and potentially it is having less of an impact during sleep. I have not heard that metformin is an issue. I take 500 mg x4 times a day. Apparently there are social media stories circulating that metformin prevents cancer and makes you live longer! I take it for diabetes, and expect no more than better BG control.

I think the breathing control issue is much like a cruise control on a vehicle that is not working well. Everything is fine until you come to a hill, and then the vehicle slows down too much, despite asking for more and more gas. Then at the top of the hill or just beyond it goes too fast, and tries to slow down. For me an event like a "hill" starts the cyclic breathing off and it can take some time to stop. The image below is typical. But, for reasons I don't quite understand things have been better over the last year. OSCAR reports 0% over the year. Before I was getting an event about once a month. I have had chronically low hemoglobin for years, and over the past year I started taking a prenatal vitamin with extra iron, and I have gotten my hemoglobin up somewhat, but it is at least within the lower part of the normal range. Perhaps the higher hemoglobin has had some effect on my O2 transport response.

Another thing you may want to do is discuss the use of an ASV instead of an APAP with your respirologist. See this link. I am quite sure it would reduce your CA frequency and CSR, but they are expensive. https://document.resmed.com/documents/products/machine/aircurve-series/product-guide/1017631_aircurve10-asv-prod-guide_amer_eng.pdf