"Minimalist" Approach to ASV

[70sSanO]

You are asking questions related to the SERV-HF study that even the medical experts can't agree upon. I have not reviewed the SERV study in any detail to know if the moralities occurred while using ASV during the sleep cycle. My understanding is that is was just a statistical study and did not analyze in depth any direct cause and effect of ASV or IPAP pressure. I have no medical background and anything I might think is not founded on anything factual, but I tend to think that it has less to do with actual IPAP pressure and more to do with the delivery of that pressure. An IPAP pressure of 20.0 is 20.0 regardless if it is continuous pressure or not.

I'm sure that some patients refused the advice and continued on ASV even though their ejection fractions are less than 45 percent. I am not aware of any study of that population; and there are so many other factors that can contribute. Both my brother and brother-in-law were in the less than 45%. Neither one was on any PAP. My brother was involved in herpetology and at the end of a weekend long show, he collapsed. My brother-in-law loved the clarinet and decided to get the band back together, so-to-speak, but after a couple of practices, it was too much for him. He never made it out of the hospital. If they had been on ASV, and part of a study, how would they be scored?

Unfortunately the only certain facts are that manufacturers and doctors will be sued if they don't error on the side of caution; even if erroring on the side of caution turns out to be the error.

Good luck with your treatment.

John

[SarcasticDave94]

That SERV study was flawed, and should be replaced with a new study soon. However, currently I think that if you score an LVEF of less than 45%, you won't get a script for ASV. And that one suffering from that LVEF number would know they have poor health due to that.

If you're concerned an ASV will cause problems, I think there's more issues to be concerned about regarding ASV pressure that isn't set right. This machine, just like other CPAP related machines, needs the pressure set to be capable of dealing with your apnea events. Those numbers may not be your minimal set numbers. In other words, your apnea events may require you to set pressures higher than you may want or like. For best therapy, you may need to strike a balance between what you think you can tolerate and what apnea events require for proper treatment. That's why it's important to post OSCAR data. The setting gurus can assist. I'm not a pressure guru, but I know my ASV, my settings, and how I got there. If you choose not to post data, and you're free to choose not to do so, that does limit the assistance we will be able to offer.

[Sleeprider]

The biggest problem with SERVE-HF was poor compliance with the use of the machines with users reporting less than 3.7 hours per use of ASV. In addition, the study involved older generations of machine with fixed EPAP pressure and minimum PS of 3.0 cm. The new ADVENT HF study has reported:

Despite its effectiveness in suppressing sleep disordered breathing (SDB), positive airway pressure therapy (PAP) is not always well tolerated by patients and long-term adherence can be problematic. Recently, two multicentre, randomised clinical trials (RCTs) tested the effects of PAP for patients with cardiovascular disease and co-existing SDB on morbidity and mortality with negative outcomes [1, 2]. Relatively poor adherence to PAP therapy (mean 3.7 and 3.3 h·day−1, respectively) in these two trials might have contributed to their poor results. Indeed, higher PAP use per day is associated with better clinical outcomes than lower use [3].

The results of the SERVE-HF suggest that users of ASV with comorbidity of congestive heart failure and LVEF less than 45% have not shown increased risk when higher compliance for therapy is present.  With more than 600 patients enrolled in the SERVE-HF study, no increased risk has been reported, and the study should be published later this year.  https://www.mdedge.com/chestphysician/ar...-no-safety  This should change the current precautionary bans on using ASV with CHF patients with LVEF < 45%.

[VisitorX]

Thanks to all of you. I will aim to post some images before long. Sleeprider -- thanks for that link; I read the article. I see at the very end that the study is funded by Phillips Respironics, so they're testing the Respironics system instead of the Resmed, who funded the SERV-HF trial. Perhaps the difference is the machine type, given their apparently very different algorithms and somewhat (I think) less "aggressive" algorithm on the PR. Some months ago, I saw some discussion about that possibility in a published journal correspondence (or perhaps it was a brief article; I can't remember which right now) some months ago.But Resmed is what I have at the moment so I'll keep working it.

[VisitorX]

This is an addendum to my immediately preceding post: If someone used (a.) supplemental oxygen (fed into the PAP circuit, to stabilize ventilation) and (b) EERS (added dead apace) when they were on *APAP*, do those interventions typically get discontinued when the person switches to ASV? Thanks.

[70sSanO]

FWIW... I believe the SERVE-HF study used a Resmed S7 VPAP Adapt. I’m guessing that machine is from the mid 2000’s, maybe as recent as 2007. But it is just a guess.

To put into perspective, the first iPhone came out in 2007.

John

Added: The study ran from 2008 to 2013.

[SarcasticDave94]

Supplemental oxygen may be continued if medically necessary. There's a ResMed ClimateLine with built-in oxygen bib if needed.

As for EERS, an ASV user recently said they used EERS with ASV. Use of the EERS would be need based and likely seen in the data and by how you feel.

[VisitorX]

Thank you. And I will aim to post tracings within a few days.

[SarcasticDave94]

You're welcome, best wishes therapy does well.