Upgrading from a S8 VPAP Auto 25 bi-level

I've had my S8 VPAP Auto 25 for nearly four years now and have been generally quite happy with it. Before that my machine was an old Respironics Bi-PAP Pro (no data) and I also briefly sampled an early model of the Respironics PR System One. I did not like the PR-S1 because of its lack of adjustments (like trigger sensitivity, timings on inhalation and exhalation, as well as rise and fall rates, etc.), but what I did like about it was its ability (or that of the software) to show the actual time/flow curve at a very fine time-scale. That is, the real-time curve of the airflow, recorded as it occurs, which allows me to tell exactly what has happened during an event of interest. With my current machine I cannot do that and it generally gives me very little data. (I should mention that I did consider the open-source SleepyHead software but it does not support smart-card-based machines.)

I have read here of people using the next generation Respironics - the S9 - being able to view an interesting statistic: flow limitation. If I understand this correctly, this might be the most important parameter for me since that part of my sleep disorders is the one that is not being properly addressed at this time. I do have OSA and that one is taken care of beautifully by the machine: my AHI is around zero, as reported by the machine. However, I have narrow nasal passages and sometimes they close enough to impose such significant flow limitation that it wakes me up completely. I'd like to be able to detect and analyze those, as well as the effects of machine pressures on it. I could tell when there is a flow limitation from the waveforms in Encore but even if the Respironics machines or the ResScan software do not report that, if I had a "flow limitation" parameter, this might be beneficial.

I've also heard that the S9 are better than the S8 in many other ways: compact, lighter, uses standard SD memory cards, and so on. My current machine was prescribed by my ENT/plastic surgeon, who will be performing another turbinate reduction procedure in three weeks. I also have a dedicated sleep doctor, but I find it more difficult to deal with him on this subject. I just called my insurance and they said the period for replacement of a CPAP machine is just three years, so I'm eligible, and there is no need for a sleep study, if the doctor does not feel it's necessary. Should I ask him for a prescription for a new machine? And what machine would be best? For instance, is there a newer ResMed product coming up that I might want to wait for? In fact, when I got my S8, the S9 was just coming out, but I wasn't aware of it, so I missed out on it.

Maybe the most useful information I could expect to get here would be about the differences in reported data between the S8 and the S9, i.e., what the latter has in addition to the former (assuming no functionality is lost). I'd appreciate some informed input.

McSleepy

A data S9 will give you the flow curve to see for yourself.

The home-machine-reported "flow-limitation" data throws some people off in the S9 in much the same way people would get overly excited about the "hypopnea" data reported from the S8s. But whatever the name, the data can be used as trending data, as it was intended, easily enough.

Autos mostly use FL info as indications of impending airway closure, but won't eliminate everyone's FLs by algorithm. Straight CPAP at a higher pressure than an auto is likely to give you might be the best way to knock out less-than-hypopnea near-events. And that can be done according to feel using any machine, with or without data.

Just my non-standard minority opinion here on the matters you mention. Those with the prevailing consensus on this board will be along shortly to give you that.

The S9 VPAP offers separate flags for Centrals, Obstructive Apneas and Hyponeas....so the addition of Centrals is offered in terms of additional AHI data. There's an apnea index and in the apnea index the Centrals and Obstructive apneas are listed as separate events going into the overall AHI.
Along with a snore graph and the FL graph.
It offers a Flow limitation graph separately in both the fixed and auto adjusting pressure modes.
It does allow for the breath by breath analysis of the air flow...both in SleepyHead and ResScan software.
No loss of any functions that I can tell.
You can go to the apnea board and request the provider manual so you can get an idea of the settings that are offered and compare it to your existing machine.
http://www.apneaboard.com/adjust-cpap-p ... tup-manual

Thank you, very much, for the information, it seems like the S9 might be a worthy upgrade. Pugsy, thank you for the effort to list the improvements in data from the S8 to the S9. I have also requested the manual from that other board.

I am looking to identify the flow-limitation-based arousals and separate them from other events. I suspect that with my current treatment I am able to eliminate all obstructive events, but I don't know what to do with FL arousals. On top of everything, it seems like I also tend to have central events (as registered during my last sleep study). For example, recently things were really bad, maybe I had an infection, which constricted my airways, and at one point I tried raising the pressure (to over 20 cm H20), and that registered on the S8 as a significant increase in AHI (well, an AHI of 7 is huge for me, otherwise keeping it well under 1). I suspect those were all centrals, but the S8 does not tag them as obstructional or "clear airway", and I don't think it could have registered them as flow-limited. It seems like the S9 would do all that, and this could be huge in determining the best strategy.

McSleepy

Check your private messages. I sent you some information on using ResScan.