Contrasting experience with PR One 560 vs A10

[Dafod]

Just re-reading the thread I started I realise I am still confused. Thanks to many posters mentioning the AFLEX but the confusion I have is I thought that was for exhalation not inhalation. I am finding, even with the AFLEX at "1" the inhalation being prematurely cut short by the 560. Is this what people are talking about?

I will now go an read more about AFLEX as, again, I thought it was only application on the exhalation.

[vsheline]

Just re-reading the thread I started I realise I am still confused. Thanks to many posters mentioning the AFLEX but the confusion I have is I thought that was for exhalation not inhalation. I am finding, even with the AFLEX at "1" the inhalation being prematurely cut short by the 560. Is this what people are talking about?

I will now go an read more about AFLEX as, again, I thought it was only application on the exhalation.

Hi Dafod,

My comments were based on Figure 1 in this study, which shows that the larger the A-Flex setting, the sooner the pressure starts dropping near the end of inhalation:

http://www.ncbi.nlm.nih.gov/pmc/articles...8.1083.pdf

I am assuming that the figure published in the study report is accurate.

[PoolQ]

Interesting, I am guessing I am glad to have not used the 560 type of product. I am on the aircurve and it turns out that I had to increase the time the machine allows me to complete an inhale. Default is 2 seconds, I tried 3 seconds and I could fall asleep fine, but would wake later in the night. I changed to 3.4 seconds and all was good. It felt like right at the end of my inhale someone was putting their hand over my mouth cutting off my air. I am guessing that I inhale quite slowly and even slower when asleep.

[Dafod]

Interesting Vsheline,
When I look at figure 1 I don't really see the end of inhalation phase impacted in such a way that would cause the inhalation to become more difficult or really vary with different AFLEX settings in a material way - yes the pressure does drop but I would assume that would be in response to the 560 sensing the exhalation. I could be misreading the diagram though. Maybe I inhale too slowly for the algorithm? I guess it depends whether the drop in pressure is based on an algorithmic timing or the user. I haven't noticed anything akin with the A10.

The reason why I am currently using the 560 is its algorithm does seem a bit softer such that while my AHI is higher (2-3 vs 0.1- 1-5) on the 560, my mouth leaks are virtually none-existent with the lower average pressure the machine tends to treat on compared to the A10. On my A10 I have noted that many of my leaks are when it aggressively ramps up in response to a perceived apnea. I don't have this on the 560 but it does seem that it makes the inhalation shorter.

[RonP]

Regarding Aflex settings, I used 3 for a long time because it seemed to be the recommended setting by most people. I was experiencing a LOT of pain with my the muscles in my chest. It was so bad that it would wake me up. I realized that the pain was worse when I inhaled. It was like I was trying to suck air through a straw or something. I changed Aflex to 1 and had almost immediate relief from that pain. I was sore for a few days but after several weeks now, I no longer have that issue.

--
Ron

[vsheline]

- yes the pressure does drop but I would assume that would be in response to the 560 sensing the exhalation.

I think the reduction in pressure toward the end of inhalation would be in response to the reduction in Flow, as the rate of our inhalation is tapering off.

"Flow" is the estimated rate of airflow into (positive) or out of (negative) our lungs.

During exhalation, a portion of the pressure relief depends on the rate (strength) of our exhalation; the higher the rate of the outward Flow, the lower the pressure drops. As the rate of our exhalation tapers off, the portion of pressure relief which is based on the Flow gradually goes away and the pressure rises part way, even though we are still trying to finish exhaling, and this effect is more pronounced when the A-Flex setting is larger.

During inhalation, similarly, judging from the figure it looks like a portion of the pressure boost depends on the rate (strength) of our inhalation. A high rate of inward Flow keeps the pressure higher, so, as our rate of inhalation tapers off, part of the pressure boost during inhalation goes away, even though we are still trying to finish inhaling, and this effect is more pronounced when the A-Flex setting is larger.

I think slow breathers would experience less pressure relief (drop) during exhalation and less pressure support (boost) during inhalation, than the average user. So I suppose the ResMed style of EPR may be more comfortable for users who breathe in or out less strongly than users who inhale and exhale with average strength.

[vsheline]

Hi RonP, welcome to Apnea Board and the forum.