Sierra

I notice spikes in my flow rate throughout the night and am wondering if these are disturbing my sleep. Any thoughts are appreciated.

It is kind of a chicken and egg thing. Do the flow disturbances cause an arousal, or does an arousal cause the flow disturbance? Hard to say. You may gain a little more insight if you expand those events a little more. You may be able to see whether the event while not flagged is an obstructive event or central event. After 4 seconds of flow interruption the machine tries to cycle the flow up and down quite fast. If the pressure goes up and down more, it concluded it is an obstructive event, and if it lasts for 10 seconds it gets flagged as obstructive. If pressure does not go up and down as much with the flow oscillation, it concludes it is a central event. You can tell the difference best if you can find a CA and OA event real close together and expand them up to see the difference.

As far as if it is disturbing your sleep if the flow goes back to normal and regular quickly that would suggest you have not really woken up or have recovered from it quite fast. If there are further events and irregular breathing that would suggest your sleep has been disturbed.

The chart for that period would indicate the machine was not operating. Yes, the ResMed has an auto stop and auto start feature providing it is turned on. The SleepStation may have the same.

If the dominant component of the AHI is central apnea is a dental appliance really going to help?

I think it is certainly worth discussing it with a heart specialist. When blood flow is lower than it should be, it can be a contributor to central apnea. Studies have found that "ASV therapy is contraindicated in patients with chronic, symptomatic heart failure (NYHA 2-4) with reduced left ventricular ejection fraction (LVEF ≤ 45%) and moderate to severe predominant central sleep apnoea." If your LVEF is > 45% you would still be a candidate for ASV.

I would also discuss with your sleep doctor the option of using the simple APAP mode with no Flex, and a reduced maximum pressure. The idea is to keep reducing the maximum pressure until the obstructive apnea starts to become a a bigger issue than the central apnea. There may be a happy spot for maximum pressure that keeps both obstructive apnea and central apnea at a low point. What is your current ratio of CA to OA events? The idea would be to reduce pressure until they are closer together.

The acceptable treatment standard for apnea is an AHI less than 5. I would suggest that is an average, and occasionally going over 5 is not a big concern. However if you are averaging over 5 that suggests a change in treatment should be considered. If the dominant part of your AHI is clear airway, that can be problematic. Clear airway is another name for central apnea. Central apnea is when you don't try to breath, whereas obstructive apnea is when you try but the airway is blocked.

Central apnea can be a sign of an underlying cardiovascular issue. I would talk to your doctor or heart specialist about the central apnea and if there is a need for treatment of a heart condition. Medications, like sedatives, especially opiods can also be a cause of central apnea.

I think there are kind of two ways to go with using CPAP for mixed or complex apnea (both CA and OA). The first approach is to minimize pressure used. That is best done with eliminating the use of Flex on a DreamStation, and also limiting the maximum pressure. The lowest possible pressure that controls the obstructive apnea part of the AHI is often the best solution. Once that pressure is found, then it can work well to just have the CPAP set at that pressure.

The second method is to try to assist the breathing by cycling the pressure up and down as you inhale and exhale. That is usually what a BiPap is used for. However, the problem is that it can result in a higher overall pressure and cause more central apnea, not less.

If central apnea cannot be addressed in any of those ways, then it may be necessary to consider an ASV (Adaptive Servo Ventilation) version of the CPAP. It acts somewhat like a BiPap to assist breathing, but changes pressure on a breath by breath basis to assist your breathing. The ResMed AirCurve 10 ASV is one example. They are quite expensive, and you need to have a special heart function test done before they will be prescribed. Those who use them report exceptionally low AHI numbers, often less than 1.

Hope that helps some,

One of the differences between a home test and a lab test is that the home test does not know when you are sleeping. When they calculate AHI they divide the number of events by the time in bed. The time in bed is a larger number than actual sleeping time, so it can understate the AHI. However your results are the opposite, so that does not explain it. The lab test is considered to be the gold standard, so, one would have to give it more weight in being right.

Does your lab sleep study report a RHI number? That includes the number of RERA or respiratory effort related arousal events. They are not counted in an AHI but can contribute to sleep disruption. Unfortunately not all insurance companies will use to RHI to approve a CPAP, but some do. If your RHI is high, you might want to try that route to get a CPAP.

I am not familiar with them, other than I am aware of some devices which make it hard to exhale causing the pressure to go up. They apparently help a little in prevent apnea. Have you looked around at pricing for a CPAP on line. Have a look at Second Wind CPAP. They have new and used machines. I would suggest the ResMed AirSense AutoSet is a good machine, and their older S9 Auto machines are pretty good too. The DreamStation Auto is also a good machine. You should be able to get one for well under $1000.

That layout is much better. I tend not to find the cumulative AHI to be that useful, unless you are having clumps of events at certain times of the night. But, even then, the event flags pretty much tell the same story. Pressure, Flow Rate, and Leak Rate are important ones. Snore can be too, but it does not seem to be a problem for you. The other one I look at on a ResMed is the Minute Ventilation. It can help identify central apnea and periodic breathing issues. Not sure if the DreamStation supplies it as a graph.

What stands out in your report and machine settings is that it appears the machine is set to Auto mode, but the minimum and maximum pressure are set to the same value - 11 cm. This makes the machine operate as a fixed pressure CPAP machine, which may not be all that bad. However, if it were me, I would be tempted to set or ask to have the minimum pressure set lower -- perhaps around 8-9 cm. This would allow the machine to have some auto control, but still limit the maximum to 11 cm. This would let you see if a lower pressure might be an option for you as you will be able to correlate when events happen with respect to pressure. If most of your central events happen at a higher pressure, it can be an indication that the higher pressure is causing them, and a lower maximum pressure might be beneficial. In short it lets you see what the impact of pressure is on your apnea events. Down the road some you may very well benefit from a fixed pressure. I have an Auto machine and after much experimentation with pressure settings, I have settled on putting it in CPAP mode and setting the pressure at 11 cm.

For local irritation when getting used to a mask, I use 1% hydrocortisone cream, but for no more than a week or so. I put it on in the morning after taking the mask off and getting up.

Hope that helps some. Any questions, just ask...

First of all there are some things you can do to make the screen shots more useful. One is to click on the black triangle beside the current data and suppress the whole month calendar. You can bring it back by clicking again, but when it is open it consumes useful space. Next is to get rid of that pie chart as it is redundant. On a PC you would go to File, Preferences, Appearance, and uncheck the box that says show event breakdown pie chart. Last if you still have the navigation bar on the right side, I believe F10 suppresses that, to give you more screen width. For the vertical direction I find you can click and drag on the graph dividers and scrunch them done quite a bit. I scrunch them until the title of each graph still fits.

As far as your results, your more recent ones are better than what you had a few days before that. The big gap on the Oct 2 report looks like the machine was off for that period of time, or at least did not record anything. The pressure chart indicates that your are pretty much maxing out on pressure at 11 cm. It may be possible you need more pressure. However, your CA or Central Apnea numbers are a bit high. Sometimes more pressure causes CA to go up. I would just watch it for a while more. On a DreamStation there are two traces in the leak rate graph. Ignore the top one. It includes the total leakage including the intentional purge leakage. The bottom curve is the real leakage. It should be under 24 L/min or so. For the most part you are under it, so leaks don't seem to be a big issue. Have you changed anything starting in October? Your results seem to have been better in October than in September, although your usage seems to have gone down.

Sorry to hear about your situation, but it is good that you are now getting CPAP treatment. I am from Canada and not familiar with the driving rules in the US. Is there any possibility of having your sleep doctor write a letter detailing what the condition is, and that you are being effectively treated. The ResMed and DreamStation machines have the ability to transmit your compliance data (AHI and hours used) to your doctor. Perhaps you could ask that your doctor or sleep clinic monitors your compliance and make that part of the letter to support that you are under treatment and are in compliance.