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AHI is getting worse. Having more centrals
Please get the ASV! Your problem does not need ST.

This is important, and I want you to understand the difference. ST means spontaneously/timed, so it cycles from EPAP to IPAP spontaneously (when you breathe), and on a timed basis when you don't. It has a fixed pressure support, so if you need 10 cm to make you breath with centrals, you get 10 cm all the time. It is mostly for people with restrictive lung disease and hypoventilation. The ST uses a fixed pressure support and fixed EPAP. You set a EPAP and Pressure Support, and a breaths per minute.

The ASV has a variable pressure support and EPAP. With the Resmed Aircurve 10 ASV you set a minimum EPAP, maximum EPAP, Maximum IPAP and a minimum and maximum PS. So you could have an auto adjusting EPAP starting at 4 and increasing automatically to resolve obstructive apnea. When you spontaneously breathe, the machine only provides the minimum PS, or will increase PS if you have a lower volume like hypopnea or flow limitation. If you have a central apnea, the machine will use up to the maximum PS to cause you to breath, before returning to EPAP. It uses the last half-hour of your breathing to determine the pace and volume of your breathing, and maintains that.

In other words, the ASV is for complex apnea and will feel natural and comfortable as it treats both obstructive and central apnea and hypopnea. The ST will feel like a robot imposing pressure whether you need it or not. If you had emphysema this would be the right solution...you don't.
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So would it be safe to say that the ST is to ASV like a Cpap is to Apap? Would the prescription for a ST work for a ASV or would it have to be a different prescription because they are different machines? It looks like the price is the same for either. Should I tell the dr that I would like the ASV not the ST machine? I looked at Supplier#10, Supplier#29 and Supplier#30. #10 had a much better price than #30. Has anyone had any experience with any of the three suppliers? I am thinking I might go with #10.
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The ST and its variants are highly suited to individuals with restrictive lung disease that need both pressure support and a backup rate for breathing. It is a technology that is being replaced by the more contemporary ASV because it can do so much more intelligently. The ST is a very limited capability bilevel that offers a fixed EPAP, IPAP and a backup rate. It does not offer variable pressure or pressure support. Very few of these machines are prescribed precisely because they don't have much of a mission, compared to more modern intelligent AVAPS and ASV. Whenever I see a ST machine in the hands of a new user, I immediately assume a mistake...yes, it's that bad.
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An ST machine did not work for me. I had my worst numbers ever using an ST machine.

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So if the dr wants to put me on a ST, how should I go about convincing him that I would do better on a ASV? Is the titration study different or the same for either machine?
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Change doctors. Seriously, tell him to do some research. Do a google search "Efficacy of ASV VS ST (spontaneous/ Timed"). ST won't even come up, but you will get lots of positive information of why ASV is the right machine for complex apnea. Bilevel S/T was an early entry to this field, but he efficacy of ASV with variable EPAP and intelligent pressure support is simply far superior. If you get a recommendation for S/T, be prepared to debate it and point out how antiquated the technology is relative to ASV, and have a couple studies showing efficacy of ASV. If he sticks to S/T quiz him on his knowledge, because there is no medical rationale to put a complex apnea patient on an iron lung.

Quote:A recent review of treatments for CompSA highlighted studies showing initial success with ASV.22 This bilevel pressure technique relies on variable inspiratory pressure to control fluctuations in tidal volume and minute ventilation to avert transient episodes of hypocapnia. Once the first commercial ASV devices became available in 2006 and the Centers for Medicare and Medicaid Services (CMS) approved their use for various forms of central apnea, interest accelerated in evaluating ASV for CompSA. One early study demonstrated that ASV was equivalent to bilevel PAP in the spontaneous-timed mode (bilevel S-T) in a group of 21 patients with mixed forms of CSA23; in the 9 patients with CompSA, ASV proved most effective. Several other studies in small groups of patients have also found ASV effective in the acute treatment of CompSA. In the largest case series to date, three-quarters of the 63 patients with CompSA exhibited a drop in apnea/hypopnea index to < 10/h on ASV.24
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Well its been awhile. Life has really sucked since my sleep doctor took back my autoset. I kept arguing that I wanted an ASV and not a ST but the dr wound't budge. He said the titration showed that the ST took care of all of the CA's I was having. Work is getting busy so I'm going to have to let it go for now and make the ST work the best it can for me. Still waiting for it though. Ended up getting my own autoset because life with out anything is worst than it was having CA's on apap. I've posted copy's of my bipap and bipap ST titration. Would love any thoughts or comments on them. The dr is setting the pressure for the ST at 25/21 with a backup rate of 12. I don't know how he thinks that that pressure is going to work. I was on it for 8 mins and woke up because it was to high and the mask started leaking like crazy. I've looked around for another sleep dr but it seems like they are all the same.

Bipap titration AHI 49.6 felt ok when I woke up
[Image: Wh78xonl.jpg]

Bibpap ST titration AHI 65.5 felt like crap when I woke up

[Image: 26zUGWbl.jpg]
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I am really perplexed at the stubborness of some doctors insisting on ST when ASV is known to be the best treatment for central and complex apnea. A new member "Herb" recently gave his doctor the boot, took his test results and found a pulmonologist that will give him the script he needs. BRAVO! I would suggest the same strategy for you!

If you are interested in self-financing, I can help you keep an eye out for an appropriate machine at a decent price. I really think you need to consider firing your doc. Does he have a conflict of interest in the equipment side? What is the reason he won't prescribe ASV?
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Told me that ASV was used for people that had CSA caused by brain damage and it's very dangerous because it's a ventilator. Completely different from all the information about ASV that I have found on the web. At this time I don't have the funds to buy a ASV so I'm stuck dealing with insurance.
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That's BS! The BiPAP ST is also a ventilator with a backup rate. The adaptive servo ventilator is an advanced machine that provides auto-variable EPAP and auto variable pressure support to provide exactly the pressure support you need to resolve central apnea and hypopnea. It only provides that pressure support when you either don't breath, or your inspiratory volume is below your normal. The ST is a much cruder ventilator that does not adjust EPAP for changes in your obstructive apnea, so it tends to be set high. It uses a fixed pressure support that is the same for every breath, and will actually cause you to have more central apnea as it will persistently keep your ventilation rate very high and blow-off CO2. It has a backup timer for when you do have centrals and fail to take a breath, but this is brute-force breathing.

Fire your doctor. Do it now. Perhaps the other "brain damaged" users of ASV on this forum can explain it better than I can...your doctor is a quack.
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