ASV Not Helpful?

[itchy365]

I have previously used a BiPAP machine but was having a lot of central apneas.  At the time, my doctor/insurance company would not support trying an ASV machine and I stopped using the BiPAP.

I found a new doctor and now have a different insurance company.  A sleep study warranted an ASV titration.  Unfortunately, the test went poorly.  My oxygen saturation dropped with ASV (which had not happened with BiPAP).  Apparently this is rare but occasionally happens?  The suggestion was to proceed with a BiPAP machine with a backup rate.

Has anyone experienced this with ASV?  I was looking forward to moving to the ASV machine. Can a BiPAP with a backup rate help with central apneas?

[Sleeprider]

If you can post the titration test results with personal information redacted, we might be able to tell more why the titration failed. ASV is not appropriate for individuals with certain thoracic diseases, COPD, or obesity related hypoventilation, and is used for those with central or complex apnea. The bilevel machines with backup rates range from the simple ST (spontaneous-timed) backup which uses fixed EPAP and IPAP pressure and a timed trigger to IPAP, to more sophisticated volume assured pressure support which target a vent rate in the patient and use adaptive pressure support. So the answer to your question is that it depends. The Philips AVAPS and Resmed ST-A both use intelligent adaptive pressure support to provide ventilation. Using the simpler ST-A will probably be uncomfortable and less effective.

[itchy365]

Thanks for the feedback.  I wasn't given the actual data but I will try to get it and post.