New Machine - Numbers Don't Match

[Hydrangea]

My numbers are different on ResMed vs DreamStation, but I feel the same. It's weird to me. All I can figure is a difference in how it measures things.

[Aardvark08]

Now that I think about it, I did have a rainout preoblem last night.  I had set the humidifier to 8 (I had kept it at 5 before) and I was awakened by a kind of thump, thump, thump at the front of the Mirage FX.  I had to shake the mask out, and tried to shake the hose, but was still having a little thumping as I went back to sleep.  As I don't know how these machines come up with these numbers, maybe that had something to do with the high numbers.  I'll study tomorrow how to make a copy of SleepyHead.   Thanks so much for all your help!

[Reznik]

Resmed and Respironics use two totally different methodologies for doing their automatic adjustments. I've read papers on how both work and, at least on paper, the Respironics methodology looks more sensible to me. Your experience seems to bear that out.

Having said that, I'm new here. I only own the ResMed Airsense 10 for Her. I'm very unhappy with its Autoset feature and have stopped using the Autoset feature. I've never owned or tried a Respironics.

[Sleeprider]

Resmed and Respironics use two totally different methodologies for doing their automatic adjustments.  I've read papers on how both work and, at least on paper, the Respironics methodology looks more sensible to me.  Your experience seems to bear that out.

Having said that, I'm new here.  I only own the ResMed Airsense 10 for Her.  I'm very unhappy with its Autoset feature and have stopped using the Autoset feature.  I've never owned or tried a Respironics.

For simple obstructive apnea, the Resmed Autoset algorithm is hands-down more aggressive and effective in preventing obstructive apnea, and preventing most hypopnea.  For individuals with borderline or actual complex apnea, it is pure hell including the EPR feature.  We could get into a lot of analysis here, but for its intended purpose the Resmed algorithms win over Respironics CPAP Auto and Flex especially when pressures are not closely optimized.  In cases where limited pressure change and Flex/EPR is desirable, either machine can produce fixed CPAP pressure, but for those individuals with complex apnea characteristics, most would benefit form a different (bilevel or ASV) technology rather than CPAP anyway.

[Aardvark08]

Thank you for the comment about Resmed and OA.  My apnea does seem to be complex.  Higher pressures tend to bring on central apneas and hypopnea to my observation. My absolutely best numbers have been produced with fixed bi-level at 8/10 PS 3, which I obviously can't do on the new Resmed.  
Oh, and I should mention that I live in the mountains of Mexico, and don't have have ready access to a sleep specialist.

[Aardvark08]

Sorry, I don't think PS 3 has to do with fixed bi-level.

[Sleeprider]

The Resmed Airsense 10 Autoset can mimic a BiPAP auto. If you used a minimum EPAP pressure of 8.0 and maximum EPAP of 10 with 3-cm of pressure support, the Autoset would be setup with a minimum pressure of 11.0 and maximum pressure 13.0 cm with EPR at 3. This would give you pressures of 11/8 to 13/10.

[Aardvark08]

I may have found the answer to my original question. I found a 2016 NCBI report of a study of the effect of the inclusion of various relaxation schemes on AHI with APAP. The long and the short as I understand it, is that use of EPR 3 on the Air Sense Auto Sense 10 makes little difference on bench measured AHI, as compared to C
PAP. but a whopping difference, 9 points or so in reported AHI. I think this is my voila: Don't trust what the machine is reporting as AHI if using EPR 3 in auto mode. Trust the outcome based on the physiological symptomology, but you can't verify. This was my suspicion all along when trying to compare results with two other machines.
Here is a link to the cogent table, which also contains a link to the entire paper. Please let me know if I am missing something: https://www.ncbi.nlm.nih.gov/pmc/article.../table/T3/

And thank you all for your input!

[Sleeprider]

The article you cite https://www.ncbi.nlm.nih.gov/pmc/article...MC4773618/ intended to compare the use of pressure relief schemes in CPAPs and APAPs of both Philips and Resmed. There are serious flaws in the method used to assess this impact, and they are the exact flaws that I described in post #9 of this thread. If the drop in therapy pressure is not compensated, by increasing the minimum pressure, then increased events will likely occur. It is however possible to use the pressure relief in the Auto CPAPs and retain efficacy.

The study set the auto CPAPs to full-range pressure rather than the titrated pressure requirement. This would mean the exhale pressure of the Resmed would not increase above 4 cm until the IPAP pressure reached 7.0 cm. The devices were set to APAP mode with open pressure range (4–20 cmH2O), and subjected to a long obstructive apneas sequence with pressure-relief features enabled. The long breathing sequence lasted 4.2 h, including a 6-min normal breathing session at the beginning, which was considered as a baseline. A 20-sec obstructive apnea occurred every minute and thus the total AHI was 58.6/h.

This would be the worst case for a real person, and we do see people arrive at the Forum with open pressure (4-20) and pressure relieve enabled. We quickly coach them to an effective minimum pressure and appropriate pressure relief which can create efficacy better than fixed CPAP. If one uses a tool improperly, it may not function as intended, and this "study" compared titrated optimized CPAP vs open settings with pressure relief. Talk about driving a nail backwards! What this study shows is that doctors and clinics should issue auto CPAPs with appropriate minimum pressure settings taking into account the patient needs and use of pressure relief. Or, patients self titrating should be instructed in how pressure relief must be compensated for by setting higher minimum pressures.

This does not explain your problem. Your issue could be resolved very easily, but it might mean actually helping us to find your therapeutic needs by producing your machine data. If you set your machine up like this mindless study, then it would surely fail. Again, read post #9.

BTW, the authors of the study do acknowledge that APAP can work with pressure relief if the autotitration pressure is "enhanced". In other words, you do have to know what you're doing if you use these features.

Similarly, in the case of APAP our findings could be relevant if the pressure range over which autotitration was allowed to occur had an upper limit that was set close to the effective (95th or 90th centile) pressure prior to activation of pressure relief. Thus, the treatment efficacy can be ensured by increasing the device pressure in fixed CPAP or by enhancing the full range of pressure in APAP. In the latter case, a well-functioning autotitration algorithm is indispensable. In addition, the pressure-relief features allocated for therapy should be enabled prior to the titration process. It should also be noted that the device-reported pressure in pressure-relief APAP is not comparable to that without pressure relief.

[Walla Walla]

I  have been cruising for years with a Respironics System One Bipap with AHI's consistently under 5 with occasional pop to 7/8. When I thought it had died, I bought a PR 60 APAP, Respironics as I did not have coverage at the time for a new Bipap. Same heavenly results, same numbers as with the BiPap. Bipap was miraculously repaired by some serious techs, and for the last year, same consistent results compared on Sleepyhead.  Enter Resmed Autoset 10 (new coverage). Bang, numbers all over the place during the last month.  Same pressures 8-15 with a 2 EPR (compared to BiPap/Apap 8-10 floating to 15) I'm. using the same masks, ditched the narrow tubing and changed the setting in the Resmed, just to compare apples to apples.  I had a 31.8 this morning, for instance! Sleepyhead showed lots of OA.  I have never seen a number like that in the last 8 years.  Resmed is onsistently showing 11-17. I'm rested, I am not suffering unusual awakenings, no open mouth dry gape syndromes. My nights feel the same as the Respironics but the numbers are telling a different story on Resmed. Any idea what's up?  I would appreciate your help. (Oh, and I live at 7200' if that may be significant)  Thanks

If I'm reading this right, here is what I Understand. Was using a BIPAP:  EPAP 8 PS 2 IPAP max 15. Went to a Airsense 10  Sets pressure 8 to 15 with EPR of 2. That would put the EPAP at 6cm. That's 2cm below what he was using on the BIPAP. Starting off 2cm lower could be enough to  collect those extra events.