Runaway pressure increase with resmed auto S8

ozij · Post by **ozij** » Tue Jul 24, 2007 10:10 pm

Comparison of three auto-adjusting positive pressure devices in patients with sleep apnoea

Response of Automatic Continuous Positive Airway Pressure Devices to Different Sleep Breathing Patterns

Bench Evaluation of Flow Limitation Detection by Automated Continuous Positive Airway Pressure Devices
Chest. 2006;130:343-349

Abstract

Study objective: Automatic continuous positive airway pressure (CPAP) devices that adjust the pressure delivered to the patient are now available to treat sleep-disordered breathing. Sophisticated auto-CPAP devices can detect and correct flattened inspiratory flow contours (FIFCs) associated with subtle upper airway obstruction. However, evaluations of their performance are made difficult by differences across patients and devices. We performed a bench study of five commercially available auto-CPAP devices using a breath waveform simulator to evaluate sensitivity for detecting flattened inspiratory flow.

Design: Five degrees of FIFC were simulated. In addition, normal and abnormal flow contours from patients published in the literature were evaluated.

Measurements and results: One device showed autotriggering leading to CPAP increases, and another device varied the CPAP level independently from the presence of an FIFC. The three remaining devices differed regarding the detection of FIFCs and the means used to increase CPAP.

Conclusion: Based on the characteristics of each patient, physicians must choose among devices with different thresholds of FIFC detection and different pressure responses to detection. Therefore, physicians need details on the algorithms used in auto-CPAP devices. Manufacturers should supply detailed algorithms

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CPAPopedia Keywords Contained In This Post (Click For Definition): auto

Slinky · Post by **Slinky** » Tue Jul 24, 2007 10:22 pm

I'd sure like to see the full article! In fact, I may just take a run into our hospital's medical library tomorrow to see if they have this journal and the article.

rested gal · Post by **rested gal** » Wed Jul 25, 2007 12:12 am

Well, when people go to read the full article(s), I hope they will also dig into this 12 page thread on this message board:

http://cpaptalk.com/viewtopic.php?t=16570
Jan 15, 2007 subject: An APAP Shootout (sort of) on Academic Journal

If you don't read anything else in that thread, I hope you'll take the time to read at least one post... -SWS's comments on page three of that thread:

Click here for Page 3

And if a person wants to really understand why studies using an artificial breathing machine to try to compare the responses of different brands of autopaps are useless as far as proving anything about how each brand of machine would actually perform with a live person, it wouldn't hurt to read -SWS's further comments in that thread. Here are shortcuts to two more of his posts in that longggg thread:

Click here to go to Page 4

Click here to go to Page 6

ozij · Post by **ozij** » Wed Jul 25, 2007 2:01 am

I agree that using a simulation will not tell you how a machine will react to a person.

However, using a simulation shows that given the same (simulated) breathing patterns various machines will react differenly. And that is the important point of those papers, and that is what should be stated firmly to docs RTs and DMEs who want us to try other brands for their own financial reasons.

On that quoted thread Slinky wrote:No way will they supply a Resmed auto loaner, their philosphy is they "loaned" me a Respironics auto and an auto is an auto. My sleep pulmo didn't script a specific brand of auto and I don't know that that would even be honored since it is a temporary loaner.

That's why we need to know about all these studies - whether simulated or real life.

I would not base my choice of machine on a simulated reaction. But I would do to my best to try more than one kind - especially if the first was not too good for me, and I would try to insist on not switching brands if I tried one that was good - even if it was the first I had tried.

Those studies (some done on patients) show that there is an objective reason why some people do better on some machines.

O.

Slinky · Post by **Slinky** » Wed Jul 25, 2007 5:28 am

We've got, what, 2 major manufacturers of xPAP machines, Respironics and Resmed; and three other manufacturers that I'm aware of, Puritan Bennet, DeVilBiss and Fisher & Paykel.

I'd be delighted to be a guinea pig and spend a week on each manufacturer's comparable autoPAP or even CPAP. But, somehow, I don't see ANY DME supplier going for that idea. Nor do I see any PRACTICING sleep doctor having the slightest inclination to write the necessary orders to allow for it nor the experience w/all five brands much less the various models w/in each manufacturer's line.

Heck, it would seem that many sleep doctors could care less which manufacturer's xPAP is provided by the DME supplier. And most seem not to even care whether the machine provided their patients is even fully data capable or not. Most seem entirely satisfied with their patients being given a compliance data capable only machine. And there seem to be way too many who don't even have any interest in the compliance data, dictate the report and FAX it off to the referring physician to write the order regardless of the referring doctor's knowledge or experience w/xPAP treatment.

The sleep medicine profession has got a long way to go, baby! It would seem the manufacturer's are WAY AHEAD of the "sleep doctors".

GoofyUT · Post by **GoofyUT** » Wed Jul 25, 2007 7:27 am

Slink-

It is OUR confusion, passivity, defeatism and resignation that permits BOTH the manufacturers as well as the DMEs to foist APAPs on us "hit or miss" with NO consideration of which manufacturer's algorithm might suit us best.

Would you deal with a pharmacy that only dispensed penicillin, or a physician who wrote a prescription for "Antibiotic twice daily by mouth (pharmacy can choose which to dispense)"??????

Ever wonder why the manufacturers DON'T feel impelled to develop different APAPs with different algorithms to more closely match the particular needs of individual patients, or even a single machine with different selectable algorithms depending on the patient's presentation and needs? It's because we are weary, sleepless, tired lambs who take what they throw at us with nary a peep of complaint or demand.

Chuck

Slinky · Post by **Slinky** » Wed Jul 25, 2007 8:27 am

*sigh*, yeah, and at that we are in the VAST MINORITY. It seems like the VAST MAJORITY of xPAPpers don't wanna know. Just mindless sheep accepting what they're given, no questions, don't even know their pressure, what machine they have, etc.

How do we beat that?? Sure, I've gotta big mouth and am not bashful about trying to get what I want and even contacting the manufacturers and telling them what I do and don't like but every one of me there are hundreds, probably thousands, of mindless sheep.

Guest · Post by **Guest** » Wed Jul 25, 2007 9:21 am

I used my resmed on auto for 6 months between 6 and 10. it mostly hovered around 7.5 and some days it was 10.2 . it drove me nuts so i set it to cpap mode at 10 where i was diagnosed. Now sleep like a baby and wont go back to auto again

Runaway pressure increase with resmed auto S8

Resignation