Why would straight CPAP be preferred over auto?

[Mosquitobait]

Had my titration yesterday and don't see the sleep doc for another 10 days. The sleep tech and I were both surprised that the doc ordered titration as a single best pressure rather than a range. I'm wondering what would be the advantage of a straight pressure? I have few apneas but some hypopneas and plenty of RERAs, especially during REM. I also have bradycardia (oxygen averages in the low 90s, but drops for long periods to low 80s). I switch between back and side sleeping, which he already knew.

Yes, I know I could wait for my appointment but enquiring minds wanna know now!

[under pressure]

There may be other reasons in addition to this that someone might address in a later reply, but first thing that comes to my mind is that some individuals are very sensitive to the pressure changes on an auto machine. In some cases the change in pressure will cause these individuals to be arroused or woken by the pressure change itself.

One solution to this issue is to use the auto machine with a very tight pressure range to keep from having big pressure swings. My pressure range is only 3 cm from lower to upper, many people begin to tighten up the range after gaining more experience with their auto results.

You might also see if you can get the Airsense 10 AutoSet in the "For Her" model which has a more gentle pressure response that is less disruptive to female breathing patterns and will be less likely to cause an arousal with a pressure change. So ask about that model and see if you can get your Doctor to write the script for that machine.

[vsheline]

Had my titration yesterday and don't see the sleep doc for another 10 days. The sleep tech and I were both surprised that the doc ordered titration as a single best pressure rather than a range. I'm wondering what would be the advantage of a straight pressure? I have few apneas but some hypopneas and plenty of RERAs, especially during REM.

Hi Mosquitobait,

It is clearly better to have an APAP machine, even if operated in fixed-pressure CPAP mode. Any doc worth his salt would see the value in being able to switch to the Auto therapy mode at least occasionally to supplement the data taken at a fixed pressure, and to adjust the fixed-pressure prescription as needed, without the expense and all the other possible issues of a new overnight titration study (very limited test duration, strange environment, different sleep positions than usual, uncomfortable, unable to sleep normally, it is known from patient comments on this and other online forums that titration studies sometimes result in pressure prescriptions which are way too high or way too low).

Maybe the doc is thinking that APAP machines (if left at their default pressure settings of 4 to 20) start at too low a pressure and may go to too high a pressure, and he does not want that. Solution: Don't leave the machine in its default pressure settings, and, if desired, operate in a fairly narrow pressure range.

I think you will need to ask the doctor for a small pressure range, even if the range is only 1 cmH2O, with the single pressure from the titration as the Min Pressure, and one cmH2O higher for the Max Pressure which the machine will use only if it determines you need it. I think you will need to insist upon this, or it will not happen, and you will be "given" (actually, of course, you and your insurance company are paying for this) a fixed-pressure machine.

You can assure him that if in your case the data during a limited period in APAP therapy mode shows it is better to operate in fixed-pressure therapy mode, you would of course be happy to do this, but only after the machine's data clearly indicates this would be best in your case.

If the doc will not work with you and claims that the data from the machines is unreliable and cannot be trusted and if he indicates that the only results which he will be using in prescribing treatment pressures are the 100% reliable results obtained by the trained professionals in the overnight sleep lab (in which he may just happen to be an investor) then he is certainly not like the average good doctor and might not be educable and you may need to refuse to go along (and may need to change doctors).

By the way, the only ResMed machine which reports RERAs is the AirSense 10 AutoSet For Her model. It reports RERA events in all three of its therapy modes, including standard CPAP mode, legacy AutoSet mode and the new more gentle AutoSet For Her therapy mode (which, if it had also been available on the standard A10 AutoSet machine, may have become the preferred choice of most men, too). No other AirSense 10 or older ResMed machine reports RERA events.

Nearly all fully data-capable Philips Respironics System One models report RERA events, I think.

Take care,
--- Vaughn

[krelvin]

I'm curious as to why the tech talked to you at all? In both of my tests there was no discussion with the tech of anything other than basic process... nothing about what they would be doing the test on or how.

The purpose of the test is to find the optimal pressure to overcome the condition you have. This will typically cover a range of pressures with results for each level as their are tested. That information will show up on the sleep study.

In both of my sleep studies it is clear they started at the bottom at straight CPAP mode and moved up in to BiLevel etc.. increasing the range as they go. The report then showed the results of various different pressure settings in both CPAP and Bilevel mode and which modes and settings responded best for my condition. I basically slept through the whole thing, having no clue what they were doing throughout the process. The second time, they didn't even bother with CPAP since I had already been using a Bilevel for 9 years. But it still showed the levels they tried, the results etc...

When I got up, the tech basically said it was a good test and that was it. Specifics showed up on the report and when I talked to the doctor. Speculation before seeing the resport was 100% speculation.

When you see the doctor is the time to talk about the machine they are going to recommend. Being prepared knowing what is available out there, and what codes they use for billing purposes will put you in the driver seat as to what type of machine you get.

[macbob]

Regarding the pressure changes causing arousals by under pressure and the Airsense 10 Autoset for Her reporting RERAs by vsheline: I have an A10 Autoset For Her, and have tested it in both APAP and Autoset for Her modes.

The difference in the modes appears to be the straight APAP mode ramps up in larger increments, and then decreases pressure quicker. The For Her increments in smaller amounts, and then decreases pressure more gradually.

Because the straight APAP mode was dropping pressure quicker it was reaching a level where I started having flow limitations quicker, and it would jack the pressure back up a little, and then it would start decreasing again. The Autoset for Her mode provided a much smoother/less jagged pressure graph.

I found the straight APAP mode was causing more arousals than the Autoset for Her mode, and I wasn't sleeping as well (though my AHI #s were similar in both modes)..

[Mosquitobait]

I'm curious as to why the tech talked to you at all? In both of my tests there was no discussion with the tech of anything other than basic process... nothing about what they would be doing the test on or how.

Much of it came up when I told her that I just started using the Resmed S9 and Wisp nasal pillows the night before. She knew I had seen my sleep report, and agreed that the range suggested here (6-12) was reasonably conservative. It was pretty clear from her response that an order for fixed rate was unusual. Anyway, I'm glad I mentioned it because she switched from the original nasal mask to a nasal pillow mask. No leaks. I was able to take what I learned home and only had one brief leak last night.

I intend to get the Airsense 10 For Her model as it has been mentioned in other threads to cover RERAs. Other than the swivel on the top instead of the side, I don't see that Respironics 60 series has any real advantage over the other model. They are subtly different, but it seems there really is no way to know which machine would be better for the individual patient unless you actually tried both machines and that isn't likely to happen according to the DME. So, I will stick with what I want.

[vsheline]

I have an A10 Autoset For Her, and have tested it in both APAP and Autoset for Her modes.

The difference in the modes appears to be the straight APAP mode ramps up in larger increments, and then decreases pressure quicker. The For Her increments in smaller amounts, and then decreases pressure more gradually.

Having the Min Pressure too low is a common problem with APAP settings. ResMed machines treat the Min Pressure as a target which they are always slowly trying to return to, with a "time constant" of about 20 minutes for the legacy AutoSet algorithm.

In the new AutoSet For Her algorithm, if the Min Pressure is obviously too low the machine will increase the Min Pressure for the remainder of the night.

From the AirSense 10 Clinical Guide:

The AutoSet for Her is similar to ResMed’s AutoSet algorithm with the following modifications:
 Reduced rate of pressure increments designed to help prevent arousals.
 Slower pressure decays.
 Treats apneas up to 12 cm H2O and continues to respond to flow limitation and snore up to 20 cm H2O.
 Minimum pressure (Min. Pressure) that adjusts according to the frequency of apneas:
If two apneas occur within a minute, the pressure reached in response to the second apnea will
become the new minimum treatment pressure until the next treatment session.

Offering a separate For Her machine with a friendlier look is fine, but because ResMed does not include the For Her treatment algorithm as one of the therapy options included in the standard A10 AutoSet model, I think ResMed is doing a disservice to its customers who buy the standard A10 AutoSet model not realizing that they are getting significantly less with regard to treatment options.

[Sleep well]

Hi
My Dr Was adamant that I used fixed pressure due to my blood pressure fluctuating as hr said it was better to have high blood pressure all night than to have it fluctating. I have polycythemia as well and have had a blood clot in my brain. He is the dr that did the work with resmed in Australia on the for her new resmed model. He said time will tell if it is of real benifit or not.
I gues your dr has the all over picture of your health in mind

Sleepwell

[Riven]

By the way, the only ResMed machine which reports RERAs is the AirSense 10 AutoSet For Her model. It reports RERA events in all three of its therapy modes, including standard CPAP mode, legacy AutoSet mode and the new more gentle AutoSet For Her therapy mode (which, if it had also been available on the standard A10 AutoSet machine, may have become the preferred choice of most men, too). No other AirSense 10 or older ResMed machine reports RERA events.

My ResMed AirSense 10 AutoSet (for him) reports RERAs. They show up in both ResScan and SleepyHead. Did you mean to say - The AutoSet A10 for Her is not the only A10 to report RERA events.

[under pressure]

By the way, the only ResMed machine which reports RERAs is the AirSense 10 AutoSet For Her model. It reports RERA events in all three of its therapy modes, including standard CPAP mode, legacy AutoSet mode and the new more gentle AutoSet For Her therapy mode (which, if it had also been available on the standard A10 AutoSet machine, may have become the preferred choice of most men, too). No other AirSense 10 or older ResMed machine reports RERA events.

My ResMed AirSense 10 AutoSet (for him) reports RERAs. They show up in both ResScan and SleepyHead. Did you mean to say - The AutoSet A10 for Her is not the only A10 to report RERA events.

There is some confusion on this point. ResMed's own literature indicates RERA reporting is only available in the "For Her" model, yet I have now heard, and or seen three people that have the regulat Airsense AutoSet that is reporting RERA.

I suspect that the ResMed literature may be incorrect on the RERA reporting only being available on the For Her model. I have found one other mistake in their literature concerning the auto climate control function. Sometimes when a new machine comes out there will inevitably be some minor changes that don't get communicated to the marketing folks.

The image below is a current publication of the Airsense feature line-up with RERA reporting listed as only available in the For Her Model