Questions about my new ASV machine

tomma wrote:Thanks guys.

I tried lowering my PS min last night, from 5 to 4, with disastrous results. AHI higher than it has been in weeks, and a lot of events. So, I've tried 4, 4.5 and 5. 4.5 is the one that seems to give me the best, most consistent results.

I think I have PS where it needs to be, so tonight I'm going to try a backup rate of 8 or 9 instead of auto and see what that gets me, that is if I can stay with it and fall asleep.

Good luck. If your spontaneous breathing rate is 10 breaths per minute, then most sleep practitioners would set your backup rate at 8 or 7 (that is if not using auto-rate).

As a side note, the closer you set backup rate to your spontaneous breathing rate, the more INVASIVE that backup rate will become with respect to normal breathing-variability times. Medical intervention generally favors trying less invasive before more invasive.

-SWS wrote:Medical intervention generally favors trying less invasive before more invasive.

Which will lead him to timed Ti after manual BPM fails?

I went with a backup rate of 8 last night, couldn't really tell if it made a difference yet though, I may have had a few less hypopneas than normal. I was up a bunch of times with a sick kid so it wasn't really the best night to gauge anything. One thing I did notice, when I had the b/u rate at 10 a few days ago it felt very uncomfortable and I had to put it back to auto, the setting of 8 was very comfortable, no problems at all. My patient initiated breaths also shot up to over 70% from around 40% when on auto.

So, I'm going to stay with these settings for a week or so and see how it goes.

I've now tried a backup rate of auto, 7, 8 and 9, but none have made a dent in the hypops, increasing PS seems to make things worse, so I'm really not sure where to go next. Trying to get an appointment with my sleep doctor but she's booked for like the next 2 months.

Any other suggestions? Would it make any sense for me to go through all the various combinations of PS and BPM I've tried? In other words, a PS of 4, with a BPM of 7, then 8, then 9,then a PS of 4.5 etc etc.

Frankly, I've found that the "AUTO" setting for BPM is the best setting for me. It does the best job of tracking my breathing and encouraging regular breathing. While you might be able to treat some hypopneas by increasing the EPAP value (the base level needed to keep your airway open) and/or increasing you PS, it's possible and even likely that some of the hypopneas are central. In that case, it's best to find a setting that works fairly well (while it might not eliminate all the centrals) .. and keep it there for a while. Most of us have found that over time the ASV therapy helps retrain our bodies to breathe on a regular basis and gradually, but surely, decreases the AHI value.

Hope that helps.

JohnBFisher wrote:Frankly, I've found that the "AUTO" setting for BPM is the best setting for me. It does the best job of tracking my breathing and encouraging regular breathing. While you might be able to treat some hypopneas by increasing the EPAP value (the base level needed to keep your airway open) and/or increasing you PS, it's possible and even likely that some of the hypopneas are central. In that case, it's best to find a setting that works fairly well (while it might not eliminate all the centrals) .. and keep it there for a while. Most of us have found that over time the ASV therapy helps retrain our bodies to breathe on a regular basis and gradually, but surely, decreases the AHI value.

Hope that helps.

I've noticed that when on auto, my patient initiated breaths were down in the 30-40% range, with a hard-coded number it's up in the 70% range. Does that make sense, or any difference one way or the other? I'm thinking I might go back to auto, but not sure what, if anything, that low patient initiated number means.

The hypopneas are almost definitely central. Maybe my best bet right now is to just figure out what's worked best so far and stick with it for a while, rather than changing after only 3-4 days, since that's not really helping.

Just an observation from another ASV user....your patient triggered breaths on the graphs you've included is around 50 percent with the machine's backup rate on 'auto'.

To me this means that either your natural breathing rhythm is irregular or you're experiencing the beginning of many events that the machine is mostly able to overcome.

The machine seems to be doing a really good job percentage wise but since you need help on roughly every other breath the small percentage of events it can't fix adds up to a significant number per hour.

10 BPM = 600 breaths/hour. So you have roughly 300 breaths/hour that the machine is intervening and only 5 aren't being treated quickly/effectively enough (1.7 percent).

The machine is 'fixing' 98.3 percent of the breaths you need help on.

Again, just an observation.

I was working on my last post for a while and this one slipped in the middle.

With 10 BPM (your average) the machine on 'auto' is looking for a breath roughly every 6 seconds...with a back up rate of 8 BPM the machine is looking for a breath roughly every 7.5 seconds.

With all things (AHI) being equal I'd think you'll feel more rested when the patient triggered breath percentage is higher, BUT is your AHI the same with the different settings? or is it higher on one setting than the other.

tomma wrote:

JohnBFisher wrote:Frankly, I've found that the "AUTO" setting for BPM is the best setting for me. It does the best job of tracking my breathing and encouraging regular breathing. While you might be able to treat some hypopneas by increasing the EPAP value (the base level needed to keep your airway open) and/or increasing you PS, it's possible and even likely that some of the hypopneas are central. In that case, it's best to find a setting that works fairly well (while it might not eliminate all the centrals) .. and keep it there for a while. Most of us have found that over time the ASV therapy helps retrain our bodies to breathe on a regular basis and gradually, but surely, decreases the AHI value.

Hope that helps.

I've noticed that when on auto, my patient initiated breaths were down in the 30-40% range, with a hard-coded number it's up in the 70% range. Does that make sense, or any difference one way or the other? I'm thinking I might go back to auto, but not sure what, if anything, that low patient initiated number means.

The hypopneas are almost definitely central. Maybe my best bet right now is to just figure out what's worked best so far and stick with it for a while, rather than changing after only 3-4 days, since that's not really helping.

Tom W wrote:
With all things (AHI) being equal I'd think you'll feel more rested when the patient triggered breath percentage is higher, BUT is your AHI the same with the different settings? or is it higher on one setting than the other.

There's always some outliers here and there but I think in the final analysis I'd say the AHI has been the same no matter what. That's what's making this so tough, it seems no matter what I try those damn hypopneas do not want to leave.

tomma wrote:... it seems no matter what I try those damn hypopneas do not want to leave. ...

As I've noted, I've seen several people (including me) find that their AHI drops .. but only after two to three months on ASV therapy. It seems to take a while for the ASV unit to help train your body to do a better job with breathing. And then it seems to be a constant set of reminders that help maintain good breathing. So, pull away the ASV unit and the breathing deteriorates almost immediately.