New guy looking for BiPAP recommendations

[gw812]

Did some searching in the topics and found some information, but it seems easier to just ask...

New guy here, did second sleep study last week and, after prying it out of them, have found out that the doc has prescribed me a biPAP. Doc has been quite good with me but I think the overall company is more interested in extracting $$$. They wanted me to come in for a follow-up visit. I ask, "What will be done during it?" Person on the phone tells me it's to discuss my 'treatment options' and I counter by stating that the doc has already prescribed the biPAP so what is the need for the office visit (a county and a half away)? After a bit of debate they tell me that if I'm already comfortable with a machine they'll just push out my appointment to the 6 week mark to evaluate its effectiveness. There's an extra $200.00 I won't need to pay. Anyway...

Been looking at biPAP machine options and, after having a couple of Scotches to help cope with the prices, am trying to find the best one for me. Definitely need a travel-friendly one so smaller is better. What do you guys recommend in this case, and what makes a 'good' biPAP 'good''? I'm a medical professional so I can speak the language but would really value some personal experience. Thanks!

[robysue]

Been looking at biPAP machine options and, after having a couple of Scotches to help cope with the prices, am trying to find the best one for me. Definitely need a travel-friendly one so smaller is better. What do you guys recommend in this case, and what makes a 'good' biPAP 'good''? I'm a medical professional so I can speak the language but would really value some personal experience. Thanks!

Assuming the prescription is for an ordinary bi-level or an auto bi-level, the two most common choices are the Resmed VPAP Auto and the Philips Respironics BiPAP Auto or Pro. The PR System One BiPAP Pro is the only non-auto adjusting of these three machines.

Here's something I wrote a while back when CatherineF was asking this same basic question.

I have to choose one of these Bipap's and I would like to know forum members opinions about them. I have moderate sleep apnea, lots of RERA'S and few centrals emerged during BiPAP titration (my doc said it should resolve over time). I couldn't tolerate straight CPAP, nor AutoPAP, that's why BiPAP.

Both the Resmed S9 VPAP Auto and the PR System One BiPAP Auto are nice machines. There are differences between them.

The three big categories of differences, in my humble opinion are:

• The comfort features
• The on-board data, the recorded data, and the software choices
• The auto algorithm itself

Which machine to chose may depend on your own needs and preferences in each of these categories.

The Comfort Features
The S9 has the ClimateLine heated hose as an option. And its anti-rainout system is based on the ClimateLine hose. The System One's anti-rainout is based in how the humidifier takes the room's relative humidity and temperature into account in how hot it heats the water and how much water it allows to evaporate into the air going into the tube.

The System One has Bi-Flex as an exhalation relief system. Bi-Flex will provide a small bit of additional pressure drop beyond that provided by simply going from the IPAP to EPAP settings. In other words, if IPAP = 15 and EPAP = 10, at the start of the exhalation, the pressure will actually drop a bit below 10 cm and then the machine will increase the pressure back up to 10cm before the exhalation is complete. (But if Bi-Flex drives you nuts, it can be turned completely off.) I believe the S9 VPAP does not have any additional pressure relief: The transition between IPAP and EPAP and back to IPAP is already a modified version of the EPR system in the S9 Elite/AutoSet. What I mean by "modified" is that in the S9 VPAP, the pressure drop at the beginning of the exhale obviously not limited to a max of 3 cm. And there is a very slight difference between how and when the VPAP and the Elite/AutoSet increase pressure back up at the end of the exhale or start of the inhale. There's an very old thread that gives a lot of details about this. You can read it by clicking here. (The thread is still there, but the wonderful images by -SWS on pages 2, 3, and 4 seem to have disappeared. )

On-board data, the software choices, and the data recorded
The on-board data on the System One is very, very limited. The AHI is only 7 and 30 day rolling averages and is not broken down at all by event type. And the System One's on-screen "Percent time spent in Large Leak" data are virtually meaningless: Not only is 1% of seven nights of data a very long time, but also PR doesn't seem to define or describe what constitutes a Large Leak anywhere. And there's the annoying fact that the System One updates its data at noon Greenwich Meridian Time. And that you can't change this. And that you can't change the clock setting---even in the clinical menu.

The on-board data on the S9 VPAP is excellent: You get nightly, weekly, and 30 AHI numbers broken down by type of event. You get 95% unintentional leak rate figures. And there's a mask-fit feature that may be useful. The overnight data is available within a minute of turning the machine off. But you do have to view the overnight data before noon local time. And you can set the clock through the clinician's menu.


As for the software: SleepyHead can be used for either of the machines, although it's still a bit buggy with the S9 VPAP Auto if I understand correctly. The newest version of ResScan should work with the S9 VPAP. Encore Viewer and Encore Pro will both work with the System One BiPAP Auto. Both machines record the following data on the SD cards:

• AHI broken down by types
• time of each event
• leak rate data
• wave form data---i.e. you can see each breath you took all night long
• some form of flow limitation data
• some form of snoring data
• pressure setting data

In addition to the above data, the S9 also records information about minute ventilation and respiratory rate. But JediMark has backwards engineered a way of recovering this data from the PR System One's flow data. So in SH you get good approximate data for these things even if you are using a PR machine.

In addition to the above information, the System One BiPAP Auto scores what it believes are RERAs. The S9 VPAP does not try to score RERAs. The problem with accurate detection of RERAs, of course, is that neither machine has an EEG for measuring the sleep state and a RERA requires an EEG arousal. The PR RERA algorithm has to be based on statistical analysis. My guess is they've identified changes in the flow wave shape that statistically correspond to the shapes of RERAs scored on PSGs. How good the PR System One algorithm is at scoring RERAs is a good question. Clearly Philips believes the algorithm is good enough to include in their commercially released products.

The System One BiPAP also flags what it believes to be periodic breathing, including Cheyne-Stoakes breathing patterns. The S9 VPAP Auto does not flag these areas of the flow wave.

The leak data on the System One is total leak---i.e. it includes the expected leak built into the mask. The S9 reports unintentional leaks---i.e. the S9 subtracts off the expected leak rate for the type mask you are using at the pressure you are using and reports any excess leak.

The S9 VPAP Auto presents the flow limitation data as a continuous graph with respect to time. In other words, it does not record "flow limitation events" as tick marks on the flow wave graph. Rather flow limitations are a separate graph. This has both advantages and disadvantages to it. The System One BiPAP Auto records flow limitations as discrete events with tick marks. But the System One BiPAP Auto records flow limitations only when it is running in Auto Mode. If you use the System One in fixed BiPAP mode, the machine simply doesn't record the flow limitation tick marks. (Editorial Comment: It seems like a really stupid decision on PR's part to suppress the Flow Limitation data when the machine is running in fixed mode. It's an even dumber decision to report FLI = 0.0 day after day in Encore Viewer.)

The snoring data is presented quite differently on the two platforms.

• The S9 VPAP Auto presents the snoring data as a continuous graph with respect to time. The scale seems to be a 0 (no scoring) to 3 (Loud snoring), but exactly what the scale is measuring, nobody knows.
• The System One BiPAP Auto records snoring data in two different ways, although this was not known to users until JediMark released an early version of SleepyHead. In Encore Viewer, the snoring data is all lumped together as tick marks on the Events table and there is a "VSI" number. Although exactly what that number is, I have not been able to determine. (Editorial comment: Given the snore "counts" available in SH, it's clear that VSI is NOT equal to (# of snores)/(time machine was on) *sigh*) In Encore Pro, the snore data is split between the snores that pop up on the Events table and those that pop up as tick marks superimposed on the wave form. In SH, the snores that show up on the wave form are called VSs. The snores that show up only in the Events table are called VS2's.
  
  And like flow limitations, the VS snores are recorded only when the machine is in Auto mode. (Editorial note: This too is a dumb decision on PR's part.) In SH, JediMark has restricted the VSnore index to VSs; unfortunately that means that users of PR machines run in fixed pressure mode see a VSnore index of 0.0 night after nigh regardless of the loudness or persistence of their snoring. JediMark is aware of this problem and I think he means to change it to NA or not report it at all in some future release of the software.
  
  JediMark has also discovered that the System One does record enough snore data for SleepyHead to provide a snore graph as well as the tick marks. The SH snore graph is based on the VS2 data, if I recall correctly. What the vertical scale measures is not known, but in general, the higher the number, the more intense the snoring seems to be. But I have no idea what "level" corresponds to "freight train" snoring and what "level" corresponds to "cat purr snoring".
  
  JediMark does present the VS2 snore data as ticks in the Event table as well as the snore graph that he draws based on that data.

The Auto Algorithms
The Auto Algorithms used by the Resmed S9 VPAP and the PR System One BiPAP auto are NOT the same. And the differences may be important to you in the sense of how it feels to use the machine all night long. And which algorithm would feel best to you may be hard to predict.

That said, here is my understanding of the differences between the two Auto algorithms:

Both the Resmed S9 VPAP Auto and the PR S1 BiPAP Auto have algorithms that automatically adjust the IPAP and EPAP pressures in response to the various events detected by the machine. But the two companies have taken quite different approaches in their algorithms. Informally this difference can be described as follows:

• The Resmed S9 VPAP adjusts BOTH the EPAP and IPAP by the same amount in response to OAs, hypopneas, snoring, and flow limitations. Like the S9 AutoSet, the VPAP tends to respond quickly to clusters of events and then slowly reduces both pressures back down at the same rate until more events occur.
• The PR S1 BiPAP Auto adjusts EPAP and IPAP independently of each other: EPAP is increased in response to OAs and snoring, and IPAP Is increased in response to hypopneas, flow limitations, and RERAs. In addition to these things, the PR S1 also uses the same "hunt and peck" algorithm that the PR S1 Auto uses to test whether the shape of the wave flow data improves with a slight increase in pressure. The hunt and peck algorithm is only applied to the IPAP pressure for increasing pressure. After events that trigger an increase in IPAP or EPAP are resolved, the S1 does a reverse hunt and peck to find out how far it can lower the pressure: As long as the flow wave remains stable, the PR keeps lowering the appropriate pressure, but if the flow wave becomes more ragged, the S1 will raise that pressure back up to the last level where the flow wave was stable

To make the some of the differences between the two machines' auto algorithms clearer, we need to introduce a setting that only Auto Bi-level PAP machines have---the PS (pressure support setting). Loosely PS is the difference between IPAP and EPAP and the value of the PS setting affects the way the EPAP and IPAP pressures are adjusted. The way PS is implemented on the S1 and the VPAP is quite different however:

• On the S1 BiPAP Auto, the PS setting is the maximum allowable value for IPAP - EPAP. And the minimum value the S1 will allow for IPAP - EPAP is 2. The upshot of this is that whenever 2 < IPAP - EPAP < PS, the IPAP and the EPAP are allowed to vary independently of each other. But when IPAP - EPAP = 2 or IPAP - EPAP = PS, there are some constraints on how the pressures are increased or decreased. In other words:
  
  • When 2 < IPAP - EPAP < PS:
    • If the IPAP needs to be increased, only the IPAP will be increased, the EPAP stays the same.
    • If the IPAP needs to be decreased, only the IPAP will be decreased, the EPAP stays the same.
    • If the EPAP needs to be increased, only the EPAP will be increased, the IPAP stays the same.
    • If the EPAP needs to be decreased, only the EPAP will be decreased, the EPAP stays the same.
  • When IPAP - EPAP = PS:
    • if the IPAP needs to be increased, then both IPAP and EPAP will increase at the same rate.
    • If the IPAP needs to be decreased, only the IPAP will be decreased, the EPAP stays the same.
    • If the EPAP needs to be increased, only the EPAP will be increased, the IPAP stays the same.
    • if the EPAP needs to be decreased, then both IPAP and EPAP will decrease at the same rate
  • When IPAP - EPAP = 2:
    • If the IPAP needs to be increased, only the IPAP will be increased, the EPAP stays the same.
    • if the IPAP needs to be decreased, then both IPAP and EPAP will decrease at the same rate.
    • if the EPAP needs to be increased, then both IPAP and EPAP will increase at the same rate.
    • If the EPAP needs to be decreased, only the EPAP will be decreased, the EPAP stays the same.
  • And at the start of the night, EPAP = min EPAP and IPAP =min EPAP + 2.
• On the VPAP, the PS setting is the fixed value for IPAP - EPAP. Hence IPAP and EPAP are always increased together on the VPAP. (And that's why the ResScan reports for VPAP mahcines can show the pressure info with only one curve.) At the start of the night EPAP = min EPAP and IPAP = min EPAP + PS.
• So the net result of all this is that on each machine, we get the following ranges for pressure settings:
  • PR System One BiPAP Auto:
    • min(EPAP) <= EPAP <= max(IPAP) - 2
      min(EPAP) + 2 <= IPAP <= max(IPAP)
      2 <= (IPAP - EPAP) <= PS
    Resmed VPAP Auto:
    • min(EPAP) <= EPAP <= max(IPAP) - PS
      min(EPAP) + PS <= IPAP <= max(IPAP)
      IPAP - EPAP = PS

Of course the big questions are: Which system is more effective? and Which system is more comfortable? As a mere patient, I haven't the foggiest if one of these systems is inherently better at treating apnea. And obviously both machines have been run through the full range of efficacy testing required by the government. But it's easy to believe that some folks might respond better to one of the two algorithms than the other.

In my case, I am rather glad (in retrospect) that I was forced to get the System One because the S9 VPAP Auto was not yet on the market at the time I was switched to bi-level. The reason I say this? It's because of my own patterns of pressure increases. On my S1, the most common reason either the IPAP or EPAP is increased is the machine detecting flow limitations and the hunt-and-peck algorithm that picks up very subtle flow limitations. Both of these only increase my IPAP. And so I start the night off at 6/4, but tend to spend significant chunks of time at 7/4 and 8/4 most nights. My EPAP rarely goes above 5cm these days. Since my old S9 AutoSet also increased pressure in response to flow limitations, I would strongly suspect that if I were using a S9 AutoSet, my EPAP would not remain at 4cm for most of the night and my guess is that it would regularly be above 5cm. And for me, aerophagia problems were a major reason for trying biPAP, and it's keeping that EPAP as low as possible that helps with the aerophagia problems. (Those rare nights I snore enough to have the machine increase my EPAP to 6cm are strongly correlated to my worst aerophagia issues.)

Pugsy, on the other hand, is bothered by the fact that when you first turn the BiPAP Auto on the PS =2 in Auto mode. And there's no way to increase that starting PS in Auto mode. She prefers to have her PS = 4 when she's lying in bed awake and the PR Auto algorithm just doesn't allow her to set it that way. So she either uses the PR BiPAP Auto in fixed pressure mode (with IPAP - EPAP = 4) or she uses a VPAP Auto with PS = 4.

So it's not that one machine's algorithm is inherently better. It's how it fits an individual's needs: I don't mind only a 2cm difference in IPAP and EPAP at the beginning of the night, but every increase in EPAP comes with a risk of triggering aerophagia. Pugsy is not bothered by increases in her EPAP, but strongly prefers being able to start the night off with IPAP-EPAP = 4. Hence, I'm better off with the PR System One's Auto mode and Pugsy is better off with the Resmed S9 VPAP's Auto mode.


Additional issues/concerns you highlight are important to you

I need quite high pressure to improve my RERA'S and hypopneas numbers (17/12 BIPAP). I've rea that PR BiPAP is better at scoring RERA'S but is this possible to score them?

The PR will at least attempt to score the RERAs. And so if you want some kind of visual confirmation that the machine is positively addressing them, the RERA data may be of interest to you. Scoring them is a bit controversial, but if you look at the wave form data in SH, you should develop a sense of when you think the machine flagged something suspicious and when it didn't.

Is this machine comfortable for someone with very sensitive nervous system?

I'm a highly sensitive individual myself. I washed out of straight CPAP @ 9cm after two weeks. I lasted for about two months on APAP @ 4--8cm before the PA suggested the Bi-level titration and it was another month of misery before I was able to get my System One BiPAP Auto. Getting the BiPAP didn't immediately fix the sensory overload problems I endured night after night during my adjustment period. But it did take the edge off of them enough to let me focus on fighting an all out War on the CPAP-Induced Insomnia. (See this post for the latest update on the War on the Insomnia). And after the Insomnia began to be reined in, slowly but surely my body began to be able to start ignoring a lot of the sensory stuff.

Eighteen months into therapy I have no desire to go back to CPAP or APAP. Running in BiPAP Auto Mode works for me and I am now comfortable with sleeping with the BiPAP---provided I get to sleep within 15 minutes or so of lying down. Any longer than that, and I tend to start noticing bothersome sensory stuff. And if I can't stop my body from complaining about the air being pushed down my throat, I'll get up out of bed for about 15--30 minutes and then try again when I'm good and sleepy. I don't often have to do that anymore.

As to your highly sensitive nervous system and your prescribed IPAP=17, EPAP=12 settings. If you use the machine in fixed pressure mode, you might not be able to tell much difference between the way the two machines feel. But:

If you are sensitive to pressure swings, both machines might be problematic. Or both machines might be fine. Or you may strongly prefer one over the other. It all depends on how well the machine's way of adjusting the pressure suits your breathing style. If you feel as though your current CPAP/APAP is forcing you to breath "funny", then you may find the other machine's algorithm for tracking breaths will fit you better. Most people find the EasyBreath pressure pattern for the S9 machines comfortable to breath with. I found it kept rushing my inhalations. On the PR BiPAP Auto, I don't feel this way. But plenty of other people will tell you that the PR System One didn't follow their breathing all that well.

The Resmed S9 is a bit quieter and hums at a higher frequency. The PR System One is a bit noisier and hums at a lower frequency. But in practice, both machines are virtually silent. Most of the noise tends to be conducted noise---often the sound of your own breathing being both conducted and magnified by the six foot hose attached to your nose.

If a heated hose is a priority, you may be much more comfortable with the Resmed S9.

And if you use Auto bi-level mode, you might very well have some additonal sensory issues with either machine. And the issues may be machine-dependent:

• If aerophagia has been an issue, you may be more comfortable with the PR System One since it will leave your EPAP alone as it increases IPAP pressure to deal with the flow limitations, RERAs, and hypopneas.
• If exhaling against your current pressure has been an issue, you may be more comfortable with the Resmed S9 because of the exhale relief created by being able to set your PS = 5 right from the start of therapy. In other words, you may find the System One's 2cm difference between IPAP and EPAP at the start of the night does not provide you with enough exhalation relief.
• How the two machine's auto algorithms respond to events bears a strong family resemblance to how the APAPs in the same family behave. The S9 responds rather rapidly with sharp increases in both IPAP and EPAP and then almost immediately starts to lower the pressure. The System One is slower to respond to events (except, it seems to snoring) but also proactively increases the IPAP by 2cm to test whether the increase in IPAP makes the wave flow's overall shape better. The System One is slower to decrease pressure after a set of events: Basically it waits until it is time to do a reverse hunt-and-peck. And so if the Auto algorithm of the APAP you have used drove you nuts with how it chose to respond (or not respond) to your particular events, then switching platforms may help you tolerate the auto algorithm better.

What is the risk of CA that can not resolve over time, i am 23 years old only, non obese and don't have any problems with my health other than extreme fatigue and sleepiness and brain fog.

That's a question for your sleep doc. But if CAs are a significant issue in your failure to adjust to CPAP then it's a question well worth asking the sleep doc. And multiple times if need be. If the BiPAP/VPAP doesn't work for you, the next step up is either a BiPAP/VPAP ST with a "T"-mode, as in a "timed-back up mode" or an ASV machine. The BiPAP/VPAP ST machines and the ASV machines can be set to act as non-invasive ventilators---and when set up this way, they can and will try to make you breathe when you have not inhaled for a set period of time or if your inhalations are not meeting a target minute volume. These machines are much more expensive and require a specialized titration study to get everything set up correctly. And judging from the posts by the ASV users, such machines can be a lot more difficult to sleep with, but are godsends to the folks with persistent CA problems that don't resolve on the lesser machines.

For now, however, I'd focus on giving a BiPAP/VPAP Auto a nice long trial---as in several months----before you declare it a failure. You need to give your highly sensitive nervous system a chance to get used to the new new.