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mdboze wrote:

Banned wrote:

dsm wrote:mdboze & banned,
The most trecent settings are looking better but I must admit I would be *very* reluctant to *ever* see my epap set below 9 even if it is being auti titrated.

I agree with you dsm,

Let's get Mdboze back to 'feeling' normal (which is probably EPAP Min 7, EPAP Max 12, PS Min 7, and PS Max 15).

Then I would ask Mdboze to trial EPAP Min 9, EPAP Max 12, PS Min 5, and PS Max 15. These settings would raise his EPAP mildly while maintaining his 'IPAP Min' at 14cm.

Banned

Banned:
On my BiPAP AutoSV Advanced, I tried the settings you suggested: EPAP Min 9, EPAP Max 12, PS Min 5, but with PS Max 13 instead of 15; Since my total pressure Max is set at 23cm, I set PS max = 13, (EPAP Min 9 + PS Max 13 = 22cm), I probably should have set it to 14, so I could at least reach the max pressure if needed while EPAP was at its min 9.

Morning Report:
I slept though the night and feel ok. I just wish I could have slept longer, but its my turn to get up with our 3 year-old and he woke up at 6am. Hmm-mm is there a setting in the machine for that ? lol.
Overall these settings worked ok; I woke up a few times; felt uncomfortable when dozing off every time, as if I was not getting enough air. Or if I held my breath, I didn't feel like it helped "strongly enough", fast enough giving me a slight urge to gasp for air. Possibly this is due to the IPAP-EPAP differece being as low as 5; causing it to take a few auto-breaths to ramp up, to get me the air I needed at a comfortable level.

I also determined that PS Max should not be above 15cm. From the BiPap autoSV reference guide, tritation protocol section: it says to stop increasing IPAP max if it is greater than 15mc above EPAP.

The "PS" setting is the pressure difference from inhalation to exhalation (IPAP to EPAP). They probably know that greater than a 15 cm difference would be too uncomfortable or somehow bad for you.

Just to clarify, in titration they increase PS MAX 'while observing PB & Centrals. If the PB & Centrals are not being adequately dealt with when the SV algorithm kicks in, the clinic will increase PSMax. The PS Max number is used by the Servo Ventilation algorithm, it isn't part of the normal epap-ipap gap. The normal epap-ipap gap is set with PSMin. If no PB or Centrals were to occur your machine would spend the night at epap & normal ipap (epap + PSMin). During the night, if your breathing rate shifts from the current target cycling kicks in (cycling is switching from epap to ipap to epap ...), or your peak average flow looks like it won't reach the current target, SV kicks in & increases the nominal epap-ipap gap for each breath that SV activity remains active. If both rate target and Av Peak Flow target are below the current targets, the machine does both cycling and activating SV pressure support.

On the advanced Auto SV there are two very important algorithms, the epap auto titrating algorithm (very slow acting - takes minutes to raise the epap pressure in response to detected osa events), and the SV algorithm, which can boost ipap by 3 CMs in a single breath in response to PB & Centrals events. SV being raised & lowered quickly & by a big gap, is very acceptable when it is being used to overcome centrals (& PB).

As I have said before, your EpapMin is rather low & thus that plus PSMin have you breathing at a very low pair of epap/ipap settings. You are relying on the slow auto titration algorithm to fix that but it takes minutes to raise epap. The SV algorithm will do it in split seconds. I suspect that setting EpapMIn so low is creating problems of its own for you adjusting to this machine. Again, if it were me, I'd get the SV algorithm running to satisfaction before activating EpapMIN / EpapMAX as that is clearly already skewing what you are experiencing.

My best advice then is deactivate the Epap Auto titration by setting EpapMin = EpapMax = whatever your clinic previously recommended as your 'normal' epap setting. I believe it was around 9 ?. By taking slow acting epap auto titration out of the procedure, you can concentrate on adapting to the machine as a bilevel with SV (fast acting). The Epap auto titration adds too many complexities at a time you are learning to get used to the machine. You can very easily activate it later. My main point - epap auto titration takes minutes to raise epap & if you have it as low as 7 or 8, you are undermining the SV algorithm.

I just realized that since the sleep study, I've lost about 10 pounds (now at 180, down from 190 lbs); With less soft tissue (ie. fat) to cause OSAs, this is probably why a EPAP Min = 7 works for me; possibly lower EPAP Min setting could work as well, while leaving the EPAP max =12 to let it auto-titrate if needed.
(from document 1032940_BiPAPautoSV_RefGd_EnglishA4.pdf)

Learning more about this every day.

Good luck with this and yes - there is so much to learn - what a journey

dsm wrote: As I have said before, your EpapMin is rather low & thus that plus PSMin have you breathing at a very low pair of epap/ipap settings. You are relying on the slow auto titration algorithm to fix that but it takes minutes to raise epap. The SV algorithm will do it in split seconds. I suspect that setting EpapMIn so low is creating problems of its own for you adjusting to this machine. Again, if it were me, I'd get the SV algorithm running to satisfaction before activating EpapMIN / EpapMAX as that is clearly already skewing what you are experiencing.

My best advice then is deactivate the Epap Auto titration by setting EpapMin = EpapMax = whatever your clinic previously recommended as your 'normal' epap setting. I believe it was around 9 ?. By taking slow acting epap auto titration out of the procedure, you can concentrate on adapting to the machine as a bilevel with SV (fast acting). The Epap auto titration adds too many complexities at a time you are learning to get used to the machine. You can very easily activate it later. My main point - epap auto titration takes minutes to raise epap & if you have it as low as 7 or 8, you are undermining the SV algorithm.

mdboze wrote:Both of these parts can be ordered from this online catalog: (a popular electronics part distributor)
http://mouser.com/catalog/catalogUSD/641/1325.pdf

mdboze wrote:Does anyone know if the smart card reader uses the same 7pin round connector ?

dsm wrote:mdboze

Take a look at this set of posts.

viewtopic.php?p=259935&sid=6120dd045a40 ... 64#p259840

The 1st pic you see is of a Respironics 'SleepLink' - I have one but not the cable. The cable though looks like it may have the connector you mention and is possibly the very cable that plugs into the machine as well.

Further down is another pic showing what Respironics call a 'SleepLink modem system' - that shows how an SpO2 probe can be connected and as per the description, with sleeplink, the RT can download compliance data only or compliance & SpO2 data simultaneously. Am not sure if that is of much use as really what we users want is detailed data + oximetry.

Muffy mentioned the port on the Bipap Auto SV may be an input port - if so it may allow an SpO2 module to be connected to the Bipap Auto SV in some configuration. I suspect this could be the case on my older Bipap Auto SV & the SleepLink card may be where the extra data is held & sent via the serial cable as shown in pic #1.

Cheers

DSM

PS I have some of these (Nonin xPods & iPods) - tried to interface one to a Resmed ResScan module - 3-wire serial interface but I could't get it to work

http://www.nonin.com/documents/ipod%20S ... ations.pdf

Snoredog wrote: Probably only 3 wires in actual use on that cable, tx, rx, and signal ground. Got a scope? take that sucker apart and see what wires are used, I'm sure it traces down to the SIM chip normally found on the card, you can do the same thing with the SmartCard if you know what you are doing, do it wrong and you 99 the SmartCard, but with that interface you bypass that problem.

dsm wrote:My main point - epap auto titration takes minutes to raise epap & if you have it as low as 7 or 8, you are undermining the SV algorithm.

Kiralynx wrote:

dsm wrote:My main point - epap auto titration takes minutes to raise epap & if you have it as low as 7 or 8, you are undermining the SV algorithm.

DSM,

While I don't pretend to understand many of the terms you and Banned are throwing around, EPAP of 9 is not necessarily low.

Please recall that my settings were originally EPAP=10, MinIPAP=10 and MaxIPAP=14. I remember you commenting that I ought to find that quite comfortable.

I didn't.

I struggled with that EPAP of ten for more than a week, fighting to breathe out again it. Many times, I choked and coughed because I could not swallow against it.

After noting that I kept waking up, and that I had event clusters at the time of awakening, I called my RT, and explained that I felt too high an EPAP was causing centrals. She agreed. My prescription was changed to the one I'm using now. EPAP=6, MinIPAP=10 and MaxIPAP=14. The apneas went away. I have a few hypopneas now and again, but otherwise, my therapy seems to be going well.

Remember -- there's no such thing as too low or too high a pressure. It's whatever works to keep an individual's throat open without causing centrals.

dsm wrote:mdboze & banned,

The most trecent settings are looking better but I must admit I would be *very* reluctant to *ever* see my epap set below 9 on a Bipap Auto SV even if it is being auto titrated (EpapMin set below EpapMax).
One characteristic of the Bipaps I have not dwelt on here, is that the CMs numbers are typically overstated by approx 1 CMs.

By this I am saying that measued with a dial manometer, the pressure at the mask is typically 1 CMs below what the LCD on the machine says. Whereas, the Vpap Adapt SV is accurate at both the mask & machine (difference is because the vpap adapt sv samples pressure at the mask).

So, when the Bipap Auto SV says 9 CMs it is pretty well for sure the actual pressure is 8. 1 CMs can be a big difference when playing around down in the epap zone. I am offering caution on trusting the epap titration at this earlyb stage. I'd get the other values (base epap, ipap & SV PS support) working smoothly 1st & then start exploring how low I can set EpapMin below EpapMax & trust it. My real point here is am instinctly nervous at the thought of epap being set so low - even if it will adjust up if OSA events are detected.
Good luck

DSM

Remember -- there's no such thing as too low or too high a pressure. It's whatever works to keep an individual's throat open without causing centrals.

dsm wrote:Ozij
DSM
(Maybe I'll stick to PM such advice as what I passed on to mdboze re that auto titrating epap challenge - but one time I did PM someone you (Ozij) specifically asked that we keep communications in the open )

dsm wrote:

dsm wrote:My main point - epap auto titration takes minutes to raise epap & if you have it as low as 7 or 8, you are undermining the SV algorithm.

And

dsm wrote: The most trecent settings are looking better but I must admit I would be *very* reluctant to *ever* see my epap set below 9 on a Bipap Auto SV even if it is being auto titrated (EpapMin set below EpapMax).

dsm wrote:I would also ask Kiralynx if I ever told her to set her epap to a particular value ? (unless I or we were being asked to suggest it) - I make a practice of not doing that if the person concerned has a sleep doctor or clinic & if I did I need to correct what I said.

I may well have & probably still will, express an opinion about epaps around 6 CMs as seeming to bevery low. BUT, I would never want to challenge a sleep clinic or a sleep doctor who has titrated someone to such an epap value.

mdboze wrote:Is the receptacle on your Sleep Link card, exactly the same as the communications port on the back of a BiPap AutoSV ?
If it is, it should look like this:

mdboze wrote: Pressure Max 23, EPAP Max9, EPAP Min9, PS Max15, PS Min6
....Good night all