A-Flex Pressure Relief - Min Pressure 6

[magicpsn]

Hello everyone!

I have been lurking for the past 6 months and learning a lot by searching past posts. I have noticed that a lot of people on the forum have or have had a low minimum pressure of 4, which is also where my RT originally had set my machine. Almost all of the posts that I read said that 4 was low and in support of all of the people that posted that said that 4 is low, I have come across information from Philips that states to "set minimum pressure at 6 H20 to enable A-Flex". I really don't know if it is required to have it higher to "enable A-Flex", but that is what it says. Here is the link that describes the "A-Flex Reflex Technology" and the minimum setting.
http://www.healthcare.philips.com/main/ ... /aflex.wpd

Rich

[Pugsy]

All it means is that at pressures below 6.0 cm AFlex option is not available. I would assume that there needs to be this amount of pressure for the AFlex do its thing. Since the exhale relief is based on flow and not pressure the relief is not a fixed drop in pressure. The Flex option has to have some wiggle room to be able to function properly.

ResMed machines have a similar feature in that the machine will not drop below 4 cm during exhale. Example would be someone with a pressure setting of 6cm and wanting to use EPR of setting of 3 which is a fixed 3 cm drop of the pressure during exhale. The machine won't go below 4 cm to the 3 cm that one would think would happen.

Pressures below 6 cm are really quite low (my titration sleep study started out at 5 cm) and at such low pressures exhale relief needs should not be an issue.

I think the Devilibiss machines offer a minimum 3 cm pressure setting while ResMed and Respironics have a minimum of 4 cm. Most people will say that those low 4 and 5 cm settings are rather stifling. While technically enough air is moving to prevent suffocation, for some people it just doesn't feel that way though. Now that I am used to my much higher pressures I bet if I tried 6 cm I wouldn't last long because that pressure would feel awfully stifling now.

The PR System One APAP with AFlex is a great machine. Do you have the software to see the inner workings going on? If not, you can find information about your options in my signature line.

[magicpsn]

Thank you for your explanation of the minimum A-Flex pressure settings. It make sense that a drop is not needed since it it so low and that at these low pressures you would not need exhale relief.

I am not sure how to post quotes for your response, but you had asked if I have software. When I purchased my CPAP machine I also purchased the Encore Viewer and downloaded SleepyHead a couple of weeks ago. I feel comfortable with the Encore Viewer, but am still trying to understand and relate to SleepyHead and trying to compare the two against each other.

I probably should start a new thread, as this is now off-topic, but since you asked about the software I will give you a little information about myself. As I mentioned I have been "trying" to use a CPAP for the past 6 months, when my daughter and myself were both diagnosed with sleep apnea. Neither of us went to a lab for a study, but were given a Respironics System One machine to use for a few days and then bring back for them to look at the readings. I had looked at several machines since I have an HSA account and would be paying for our own equipment. Originally I had selected a Resmed machine, based on the reviews that I read, but the RT talked me into the Respironics and even though he said I didn't need the A-Flex he was not against it an wrote the prescription to cover "any machine" and "any facemasks" that I would want. I wanted a full-mask since I have nasal issues, but the RT said to just use the same mask that I used for the test (which the RT let us keep - nasal mask). I tried using this mask, but after a few days it caused sore areas from pressure and at times had difficulty breathing due to nasal passages becoming plugged at night, so I stopped treatment. On the followup visit with the RT (approx 1 mo) I told him that he will see a low compliance and that I wanted to try a full face mask. He recommended that I try nasal pillows and turning up the humidity, which I did with the same results. I went back for a face mask fitting and purchased and tried one but would wake when I laid on my side, as the mask would leak. About a month ago I purchased a Hybrid mask and I LOVE it!!! To me it is much more comfortable than any of the others and with the combination of choices for mask and pillow customization makes for a great fit.

To me, it has taken a long time to get to where I am currently (6 months)...which I feel is really the beginning of my CPAP adventure, since I now have a mask that "works for me" and I can focus on settings.

My original CPAP setting that the RT set was Min 4 and Max 9. I do not know what the RT saw as I do not have that data, but in my current data, for the early period, I saw a lot of days where the <=90% was at my Max of 9. A couple of weeks ago I changed my settings to Min 6 and Max 13. On the daily, I see several days where the <=90% is 11 and some 12s, but the average for the two weeks has been 9.7. Even though I have had a cold this past week, I feel better and more rested. It may be that a week of this was from Christmas to New Years and that I did not have to wake up early and go to work!

I am still trying to figure out how to "interpreting" what the software is showing and what changes would be best.

Well, I guess that's enough rambling from me.

[Pugsy]

SleepyHead software will give you the flow graph showing each individual breath if you wished to view it.
Encore Viewer does not offer this wave form or flow data. New people till they get used to all the terms and how it relates to their therapy will find all the data that SLeepyHead shows over Encore Viewer, or Pro for that matter, quite daunting. With time and use and education you will pick more of it up and understand things better. I have used Encore Viewer, Encore Pro (DME version) and now recently SleepyHead. My preference is SleepyHead but then I had the others for over 2 years to get used to.

The 90% pressure thing is not really all it is cracked up to be sometimes. It is just a number where we spend 90% of the time at that pressure OR below that pressure. Sometimes it happens to coincide with what pressure might be needed if someone wanted to change over to straight cpap mode. Sometimes the 90% pressure number can be elevated if the machine increases the pressure trying to fix the leaks. Sometimes it gets elevated due to a particularly stubborn session of apnea events.

For new people I suggest that they look at AHI and Leak line. Leak line doesn't have to be perfect and as long as we don't spend a huge amount of time in Large leak then we can trust that the AHI shown is accurate. We aren't ever really told an exact line where Large leak comes into play but from past experience it seems to be around 90 L/min when reporting Total Leak (which is what Encore Viewer reports). AHI under 5 and leak under 90L/min....pretty much the basics.

I am working on a SleepyHead tutorial to help explain what it all means. It is pretty rough right now but some questions might be answered if you glance at it now especially some definition of terms.
It is the SleepyHead Tutorial under construction thread on the front page here.

Masks....as you have found out the mask issues are the toughest to solve sometimes. Now that you have found a mask you like then you can move forward and concentrate on making sure your therapy is effective and get the hours of sleep you need.

If you have specific questions about something you see on your reports from either software if you will post a copy of the report with your question then someone can explain things in better detail.