A ResMed Funded Test of APAP Machines

[sptrout]

I highly recommend that any one interested on how well different brands of APAP machines adjust their pressure through the night based on sleeping patterns watch the video at the link below. I know many people on this Board do not like "Uncle Nick" from SleepHQ for some reason, but in this video he is the messenger, and teacher, of a study funded by ResMed (link to the actual study contained in the show notes). Surprising results and may make you think twice if you are setting your APAP pressure ranges correctly. ResMed may have wished that they spent their research money elsewhere.

https://www.youtube.com/watch?v=v6_NHkXgSRU

[chunkyfrog]

No test is necessary--and I refuse to watch a video.
Would you terribly mind writing a summary?

[babydinosnoreless]

Wow that guy is obnoxious. I only watched a little bit before I got disgusted at his claiming a 4.0 ahi night was good sleep. I'll stick with my resmed sledgehammer thanks.

[Rubicon]

Would you terribly mind writing a summary?

https://journals.plos.org/plosone/artic ... ne.0151530

[Rubicon]

I know many people on this Board do not like "Uncle Nick" from SleepHQ for some reason...

Actually, it's him that don't like us:



but that's OK. Gets the blood moving.

[MrPaapoo]

do not throw out the baby with the bathwater...
OP's mistake was to put the link to the video, which is not very interesting, and makes hasty and random conclusions as usual. That said, the study itself is worth reading. You learn a lot about how the machines work, and what the differences are between them.
Here is the link, without comments to distort them. https://journals.plos.org/plosone/artic ... ne.0151530

[zonker]

do people NOT read the whole thread before replying?

[Pugsy]

do people NOT read the whole thread before replying?

Heck, most of the time I wonder if people bother to read the whole first post before replying.
I already know they don't bother reading what others say.

I find uncle nicko highly annoying...the say the least. I don't bother with his videos.
Maybe later I will read the research paper...or maybe I won't.

[chunkyfrog]

I will not--unwilling to accept cookies, (if flavors unknown.)

[sptrout]

I find Uncle Nick's videos both entertaining and very informative. For example, one recent video he compared the recommended parts (air filters, hoses, etc.) replacement schedule for the exact same device, but one from the USA Manual the other from the Aussie Manual. The recommended replacement schedule were very different; the USA being much more aggressive in replacements than the Aussie version. Why??? Could it be that the USA Manual was just matching the Medicare Guidelines? Anyway......

The video that I linked to was of Nick describing the Study, its methods, devices used, and the test results of each device. The Study was published on March 16, 2016 (as usual for med studies, must have been buried), and compared the test results of ten APAP machines. All except ResMed had just one device tested; ResMed had two; the AirSense 10 & AirSense 10 for Her (Nick noted that the new 11 Model would be the same since the 10 & 11 are basically the same thing except for user interface). ResMed funded the study (actually per the Study Notes just paid the salaries of the authors, but had no other involvement with the Study); I am sure much to ResMed's regret after seeing the results.

The Study was designed to test the APAP proprietary algorithms of each device to see if they were successful in accurately diagnosing and correcting various SA events. The methods used are described in detail in the study and explained in more easy to understand terms in Nick's video discussion. The paper is rather complicated and it really helps to get a good understanding of all the details from Nick's video.

As already mentioned, 10 machines were tested with ResMed getting two entries into the Study. If you look at page 5 of the Study, the two ResMed machines are labeled A & B (the machine vs. letter assignments are shown elsewhere in the Study). I assume the majority of the members of this Board use either of the two ResMed devices, so their results are likely the most important, but the other machines are of interest also.

If you look at the ResMed graphs on page 5 you will see a very disturbing pattern. (BTW - - All machines in the Study were set "wide-open" 4-20). Both patterns look like the blade from your favorite saw; sharp vertical rises followed by a rather fast decline. The levels are far above what was necessary to correctly respond to any detected breathing change and could easily cause sleep disruption from either the sharp rise in pressure in the user's face, or the increased likelihood of leak problems. Note that the "for Her" model was better than the standard model, but still poor, or really just plain bad. The other brands of APAPs had their own problems, but 2 or 3 did fairly well.

One other item that I found interesting was the APAPs reaction to the first 50 minutes of each test. The first fifty minutes simulates the user being awake and breathing normally, therefore, the APAP machines should just sit at 4ccH2O waiting for the user to fall asleep and start having breathing problems. On the 10 graphs this 50 minute "awake" time is easily seen on the left side of each plot; a straight line at pressure level 4. If a machine is responding correctly it should be doing nothing except providing a level 4 pressure. However, look at the various machines, some go straight to a very high pressure and others climb but not as high. Most of the machines try to start correcting a non-problem; a couple remained at or near 4. As Nick mentions in his video if using one of the machines with fast rising pressure you may want to use the "ramp" feature to help control these rockets.

Since most of us all already have a specific brand of of APAP machine, you may want to look closely at the results of your machine's test.

I have two main takeaways from this Study.
1. Make sure that you control the "awake" pressure since this could be reoccurring each night and even maybe multiple times per night if you wake for one reason or another and have to restart your machine.
2. Do Not leave your APAP machine pressure set to "wide-open" unless you absolutely have to due to severe SA issues. If you do leave it wide-open you can see what happens with your machine. I have 4 ResMed 10 machines and I have seen the sawtooth pattern many times before I reduced the maximum pressure considerably. I now have my machine set for a low of 6 (could be lower I expect) with a high of 9. My AHI is nearly always less than 1, mostly between 0 - .5. each night (from OSCAR; my 30 day AHI average as of this morning is .32). Before I reduced the maximum pressure from I believe it was 15, I was having several CAs each night; almost certainly caused by excessive pressure. I seldom have CAs at the reduced pressure. I hate to say this: But, according to Nick's recommendation the maximum pressure does not need to be much more than the "95% Pressure" as shown on the OSCAR Statistics page. I use the "7 day 95% Pressure" reading of 8.94 to set my max pressure to 9.0. As I mentioned already, the results are great. Low AHI, no sleep interruptions from unnecessary high pressure, and no leaks.

[sptrout]

"Actually, it's him that don't like us:"

Not true. He has never mentioned this Board or even referred to this Board or any other SA Board. He was just pointing out that some scumbag (my words not his) was posting false information and using new IDs each time to avoid detection. I never read any of these bomb posts that I know of. Not surprising there are so many posts each day that I cannot keep up with them all. I am sure that no one on this Board would want someone posting false information just to stir-up trouble.

The SleepHQ Board is growing rapidly and has members from all over the world, but mainly from the US. Many mention that they have tried to find help elsewhere but were unsuccessful. I guess they do not know how to use Uncle Google or I think that this Board, and others, would show-up in the search results. Not too surprising since it is obvious that many posters on SleepHQ, and maybe here, have very little computer experience.

[chunkyfrog]

Testing efficacy while the machine is set WIDE OPEN (4-20)
sounds like somebody ASSumed those settings work . . .
"Don't quit your day job--voluntarily."

[robysue1]

Would you terribly mind writing a summary?

https://journals.plos.org/plosone/artic ... ne.0151530

It's worth pointing out that the study is not about making APAPs better at treating apnea. The study is about finding a better way of a sleep apnea patient's breathing to evaluate whether an APAP is adjusting the pressure appropriately and flagging events correctly: The paper's title is Novel Approach to Simulate Sleep Apnea Patients for Evaluating Positive Pressure Therapy Devices.

In other words, it doesn't really tell us patients any more than we already know about how our machines actually track our real, non-simulated breathing and how they respond to what's going on in our real, non-simulated breathing.

But I will admit: It's good that Resmed (and presumably other manufacturers) are interested in figuring out good ways of testing these devices while the device is still in the design stage and they're not ready to do a study using real patients in a real sleep lab.

[sptrout]

Testing efficacy while the machine is set WIDE OPEN (4-20)
sounds like somebody ASSumed those settings work . . .
"Don't quit your day job--voluntarily."

The pressure each machine went upto never reached 20, 15 I believe was the highest. I have seen mention somewhere in the past that it was okay, even recommended, that the APAP pressure be left at factory default 4-20. I am sure that poor folks that get their machines from a dumb DME with and even dumber sleep doctor (I have one of those, dumb as a stump) have their machines set at default and never know that they are setting themselves up to fail and want to trash CPAP/APAP therapy because of hating the high pressures.

[chunkyfrog]

No doubt the biggest reason so many apaps end up in a closet.