Respironics PR System One REMstar Auto w/A-Flex vs. ResMed S

General Discussion on any topic relating to CPAP and/or Sleep Apnea.
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Respironics PR System One REMstar Auto w/A-Flex vs. ResMed S

Post by __z0rk » Sun Jun 05, 2011 10:38 pm

I am currently leasing a REMstar with the option to buy, but I've been eyeing the ResMed. Any thoughts? PROS or CONS? or is it just a matter of personal preference?
Polysomnogram study results:
AHI = 31.6
RDI = 20.2

Dx: Severe obstructive sleep apnea
Started CPAP: 06/02/2011

Pressure: 5-20 cm H2O
Ramp time: auto

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Re: Respironics PR System One REMstar Auto w/A-Flex vs. ResMed S

Post by codinqueen » Sun Jun 05, 2011 10:59 pm

I have a ResMed S9 auto CPAP with the H51 Humidifier and Climateline hose, and I like this machine. It is data capable and you don't need to buy a special card-reader for it. Only thing I don't like is that the hose comes out of the back of the machine instead of the front, so the way it needs to sit on my nightstand makes reading the screen difficult, since it is upside down in that position from my bed. I don't know about the other machine so wouldn't know how that hose attaches. It is quiet in its' operation and spouse's sleep is not disturbed while I use this machine. The machine I had 10 years ago was noisy and kept both of us up all night and I couldn't get used to it, but I don't remember the name of it. This S9 and the Swift FX mask allowed me to acclimate to CPAP very quickly.

Machine: S9 AutoSet™ CPAP Machine
Mask: Swift™ FX For Her Nasal Pillow CPAP Mask with Headgear
Humidifier: S9™ Series H5i™ Heated Humidifier with Climate Control
Additional Comments: Clear by Pur-Sleep to keep nose open at night, Cozy Hose-Boss by Pur-Sleep
Pressure 6-10 cm

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Re: Respironics PR System One REMstar Auto w/A-Flex vs. ResMed S

Post by DougVK » Mon Jun 06, 2011 1:52 am

__z0rk wrote:I am currently leasing a REMstar with the option to buy, but I've been eyeing the ResMed. Any thoughts? PROS or CONS? or is it just a matter of personal preference?
Is your insurance paying for the machine at all?

If you are going to have to spend hundreds more on the s9 it probably isn't worth it. If the s9 is only going to cost you slightly more or nothing more than get the s9, I hear it has a few benefits over the System One.


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Re: Respironics PR System One REMstar Auto w/A-Flex vs. ResMed S

Post by cowlypso » Mon Jun 06, 2011 6:29 am

It seems like it's pretty much a toss-up. At my DME, the RT I saw for my initial set-up said that he prefers the System One because the C-flex is better than the EPR on the S9, and he thinks it's better on auto than the S9. I saw the other RT a few days later, and she said that she prefers the S9.

The S9 does give more on-screen data, but they both record the same stuff. Since I download my data every morning anyway, I never look at the screen so the lack of the data displayed there doesn't bother me. Also, the S9 has a "prettier" screen.

As was mentioned above, a big pro of the System One is that the hose comes out of the top of the humidifier, which results in less wear and tear on the hose.

Another difference between the two machines is how the patient can adjust the ramp without going into the clinician's menu. On the System One, the ramp starting pressure is easily adjusted, but to change the ramp time you have to use the clinician's menu. On the S9, the ramp time is easily adjusted, but to change the starting pressure you have to use the clinician's menu.

It seems like it's really just a personal choice. They are both good machines.

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Re: Respironics PR System One REMstar Auto w/A-Flex vs. ResMed S

Post by robysue » Mon Jun 06, 2011 7:40 am

I've used both the S9 AutoSet and the PR System One BiPAP Auto.

The most noticeable differences from the user's point of view are:
  • Where the hose come out of the machine: On the S9 it comes out the back of the humidifier; On the System One, it comes out the top on a rotating cuff. The System One's placement is easier on the hose, but a bit uglier to look at.
  • On-board data: The S9's is really great and provides enough detail where you don't need to download the data to the computer every single day just to see a good snapshot of what's going on. The System One's on-board data is pathetic.
  • Software: ResScan can be downloaded for free by finding a post by Uncle_Bob. EncoreViewer can be purcased for $99 from our host and EncorePro can be downloaded from various torrent sites. EncorePro is much harder to install and slower to run. You can get around purchasing EncoreViewer if you're willing to use the alpha version of SleepyHead or Onkor. SleepyHead's author says he plans to add support for the S9 at some point in the future. ResScan's presentation of the detailed data is a bit harder to use than either EncoreViewer/Pro or SleepyHead. There's no flow data available in EncoreViewer, but the flow data is easily viewed in EncorePro, SleepyHead, or Onkor. SleepyHead and Onkor do as good of a job displaying flow data as ResScan. The flow data in EncorePro is static (no zooming) and is shown in five minute intervals over several pages.
  • Exhalation relief: EPR and Flex do not work the same. For most people the slight differences probably don't matter. But if you are really sensitive to pressure changes, you may well develop a strong preference for one or the other system. My personal take on the two systems is this:
    • PR Flex systems: The increase back up to full pressure occurs about halfway through the exhale---well before the inhale starts. The amount of pressure relief varies from breath to breath and is based on how forcibly you are exaling: The stronger the exhale, the more pressure relief there is. Personally I do not like Flex because I feel that increase in pressure and it makes me feel like the machine is trying to force me to inhale again. Fortunately Flex is easy to turn off.
    • ResMed's EPR: The increase back up to full pressure occurs much later in the exhale. The exact same level of pressure relief is delivered on every single exhale and the amount corresponds to the EPR setting. Some folks say that the S9 with EPR turned on behaves like a bi-level wit IPAP-EPAP restricted to 1, 2, or 3cm and that the increase doesn't start until you start inhaling. But that's not what it felt like to me. In my normal breathing pattern there is a slight pause between the bulk of the exhale and the start of the inhale when there is very little air moving out (or into) my lungs. Psychologically I regard this pause as part of my exhale. The EPR system starts to increase the pressure during that pause---or so it seemed to me. So I felt like the machine is trying to make me inhale sooner than I wanted to on most breaths. But even so, the EPR system felt less abnormal to me than BiFlex on my current machine does. (So I don't use BiFlex because I'm getting all the pressure relief I need just from having the bi-level machine in the first place.)
  • Ramp: As someone else pointed out, on the S9 the user can control the ramp time, but the starting ramp pressure can be changed only through the clinician's menu. On the System One, the user controls the starting ramp pressure, but changing the ramp time can be done only trough the clinician's menu. Both systems are stupid in restricting the user to only part of the ramp settings.
  • Humidifier and rainout prevention systems. On the S9, the humidifier can be adusted in half steps giving the user something like 10 different settings. Rainout prevention is only available if you use the fancier, more expensive, and possibly more delicate ClimateLine hose. On the SystemOne, the humidifier as two modes (classic and the default fancier "anti-rainout" mode) with 5 settings in each system. The default "anti-rainout" mode works by adjusting the amount of provided heat & humidity based on sensors sampling the room air. The rainout mode works with any hose.
  • Auto algorithms. Both machines respond to OAs, flow limitations, and snoring by increasing pressure. The System One also raies pressure for hypopneas and machine-scored RERAs. The S9 doesn't attempt to score RERAs and I believe that the S9 does not respond to hypopneas. Somebody with an S9 Auto PLEASE TELL ME IF I NEED TO CORRECT THIS!. Neither machine increases pressure when the machine detects a CA. The System One has a hunt-and-peck algorithm where it periodically raises the pressure by a cm or two looking for improvement in the wave form data. If it sees no improvement, it then lowers the pressure back down to the original level. This is what gives the pressure graph is characteristic sawtooth bumps in Encore. After raising pressure in response to events, once the wave form data is nice and stable, the System One does a hunt-and-peck in reverse for lowering pressure. The S9, on the other hand, prefers to aggressively respond to events by quickly raising pressure until the point where the events resolve and the wave form is stable. Then the S9 starts to slowly decrease pressure until either more events start or the min pressure is reached. Both systems can cause problems for people sensitive to increasing pressure. Which is best depends largely on comfort. And for most people, I don't think they'll be able to tell the difference.
  • Method for detecting CAs vs. OAs. The System One uses pressure pulses (PP) to determine the patency of the airway. These are short "puffs" of air on top of the current pressure setting. Tey show up as little red boxes in the wave form when you look at it in EncorePro or SleepyHead. The S9 uses a forced oscillation techinque (FOT) to determine the patency. The FOT consists of many short low amplitude oscillations in pressure over a 6 second period (if I recall). The FOT starts about 4 to 6 seconds after the machine detects the airflow has dropped to 0. People sensitive to pressure changes can easily be bothered by the PPs or the FOTs. Which one will bother a person more depends on the particular person. When I was switched to the PR S1 BiPAP I was actually worried about the PPs since the S9's FOTs did bother me. However, my body has either become less sensitive to such things or the PP's don't last long enough to bother me because I personally find the PPs bother me less than the FOTs did.
  • Traveling case. The S9's parts must be disconnected to pack them in the travel bag. The System One's do not. Of course both require that there be no water in the humidifier before being packed. I personally find the shape of the System One bag to be very, very awkward since it is not "flattish" in any direction. The S9's travel bag was much more flat and easier to deal with.
  • Sound levels: The S9 seems to be a bit quieter, although both machines are very quiet.

Machine: DreamStation BiPAP® Auto Machine
Mask: Swift™ FX Nasal Pillow CPAP Mask with Headgear
Additional Comments: PR System DreamStation and Humidifier. Max IPAP = 9, Min EPAP=4, Rise time setting = 3, minPS = 3, maxPS=5

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Re: Respironics PR System One REMstar Auto w/A-Flex vs. ResMed S

Post by __z0rk » Mon Jun 06, 2011 9:22 am

Thank you so much for all your feedback. This detailed information is really useful and informative.
Polysomnogram study results:
AHI = 31.6
RDI = 20.2

Dx: Severe obstructive sleep apnea
Started CPAP: 06/02/2011

Pressure: 5-20 cm H2O
Ramp time: auto


Re: Respironics PR System One REMstar Auto w/A-Flex vs. ResMed S

Post by guest6of6 » Sun Jun 12, 2011 12:53 am

I have a "S1" and "S9" setup in my bedroom right now. Both are CPAP and *not* APAP. I'm a new CPAP user (two months)...

I find the S9 superior in almost every way. I see people admire the S1 for its hose swivel, power input swivel, ability to see water level from the front (?!?!)... like any of that *really* matters.

For me, the S9 is a diamond while the S1 is chipped glass.

The S9 is much more quite than the S1. This is my opinion and my spouses. Not only is the S9 quieter, but the noise that it produces is less annoying. The S1 produces motor (wining) noise while the S9 noise is simply the sound of air. Both machines are set to maximum exhale relief (I believe I already said I'm a new CPAP user).

I like humidity and my S1 always runs dry (actually, it always has about 30ml left in the tank; the heat plate is too small). The S9 never runs dry and provides excellent humidity (I'm using SlimLine tubing only and *not* the ClimateLine heated tubing). I also like the S9 humidifier preheat function.

Exhale Relief:
I find the S1 pressure to "race" back to quickly. I'm half exhaled and it jumps to full pressure providing no exhale relief at all. The S9 exhale relief is far more like real breathing (for me) as it increases pressure with the inhale.

I could mention more things (I'll mention the YouTube video of a S1 sales rep. claiming/lying about their machine measuring humidity temperature at the mask because they know how much temperature is lost through the tubing... BS!!).

Obviously, I prefer the S9 in every way that *I* think matters. Unlike some others, I will say that I'm not affiliated or will profit from the sales of either machine.

I hope the above helps some folks that have searched so hard (as I did about two months ago).


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Re: Respironics PR System One REMstar Auto w/A-Flex vs. ResMed S

Post by rested gal » Sun Jun 12, 2011 3:58 pm

I had an opportunity to try both a Philips Respironics System One REMstar Auto, and a ResMed S9 Autoset.

My personal preference (bear in my I'd been happily using Respironics machines for seven years) after trying out both machines for one night each: the ResMed S9.
S9 VPAP Auto - S9 Auto - BiPAP Auto - 420E auto - Everest 2. ResScan, EncPro & SL3.
Humidifier: F&P HC 150, Aussie heated hose.
Mask: Aeiomed Headrest/homemade straps.
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Re: Respironics PR System One REMstar Auto w/A-Flex vs. ResMed S

Post by ellis66 » Thu Jun 16, 2011 11:29 pm


I have the same hesitation and want to hear if you already decided which machine to buy. Anyway, love to share from you.