Fine-tuning APAP for CSA?

[spclark]

Would like opinions (please) on whether there are things I could change to reduce/preclude side effects that may occur with long term use. Have requested clinical manual via e-mail so for the time being I'm making minor adjustments then monitoring what effects might result.

Profile specs'll tell you what I'm using (for device) then attached image from OSCAR report'll show where I'm presently setting things. AHI's 0.7 - 4.7 for consecutive nights over two weeks after enabling VPAP Auto per Rx recommendation.

[Sleeprider]

spclark, normally we see central apnea are reduced with lower pressure and less pressure support. It's unusual to see someone that has any significant central sleep apnea do well with a bilevel with pressure support over 4 cm. I suspect your apnea is predominately obstructive, and the centrals are just an artifact of the therapy. You are using Vauto mode with an EPAP min of 9.6 and maximum IPAP of 17.6 with PS 4.6. These are rather bizzare settings, and I'm curious how you got to them. With the full chart, we can see the relationship of events to pressure and give you better advise, but since your efficacy looks pretty good here, I think I will simply suggest going into your settings and set the Trigger Sensitivity on high. We have found this often reduces stray central events. I might drop pressure support to 4.0.

[spclark]

spclark, normally we see central apnea are reduced with lower pressure and less pressure support. It's unusual to see someone that has any significant central sleep apnea do well with a bilevel with pressure support over 4 cm. I suspect your apnea is predominately obstructive, and the centrals are just an artifact of the therapy. You are using Vauto mode with an EPAP min of 9.6 and maximum IPAP of 17.6 with PS 4.6. These are rather bizzare settings, and I'm curious how you got to them.  With the full chart, we can see the relationship of events to pressure and give you better advise, but since your efficacy looks pretty good here, I think I will simply suggest going into your settings and set the Trigger Sensitivity on high.  We have found this often reduces stray central events.  I might drop pressure support to 4.0.

OK, thanks.

I'll drop PS to 4.0 then. This is a baseline pressure setting on top of which EPAP / IPAP are 'heaped'? Helps knowing what abbreviated labels mean...

Already have TS set to V. High.

Will post updated screen-shot once I've slept with those numbers for a few days this week.

[SarcasticDave94]

PS is added to EPAP, in your case, if you edit it to PS 4.0, it constantly makes IPAP 4.0 cmH2O more than the Auto adjusting EPAP.

[Sleeprider]

I'm pretty sure you can slowly titration back the PS setting and arrive at a point where therapy remains comfortable, and relatively free of CA events.

[spclark]

OK so the settings are additive in nature. That's helpful, why I asked for a clinical menu manual to be sent. Thanks....

I've lowered PS to 3.6.

Leaving Ti Max @ 4.0 seconds, TiMin @ 0.2 sec., see what happens this week.

Before discovering the Clinical Menu I was plagued by I pressures cutting out then back in again when inhaling. Most disruptive to my falling asleep with RAMP set to off, even with Ti Max set to something less than the 4.0 seconds max. allowed.

Glad I stumbled on this forum earlier today. Getting useful info after initial posting, rather than crickets to what I'd posted over on another forum I found a week ago.

You responders able to 'read' graphed data from OSCAR that's hiding things I might benefit from knowing? There's more to what it gets out of raw data brought over off that SD card from my ResMed than I can wrap my head around.

[Sleeprider]

Well, you're yet to post a complete graph, but let's wait for you to try the lower PS, and we can give it a go tomorrow. As far as TiMax time, I don't think you need to go to 4 seconds. Your 95% is at 2.22, so above 3.0 that you're accommodating very little. I use that as well, and it really doesn't make much difference. We use the feature to cause some individuals to cycle to exhale, if they need that time. The default of 2-seconds is short for some, and you (like me) have a high tidal volume, so it all makes some sense. With therapy onset CA events, it's mainly about the increased ventilation from pressure support that drives down CO2. It's called the apneic threshold, and this is a common problem.

[SarcasticDave94]

Agreed on Ti Max sounds a bit high.

[spclark]

Received the requested clinical manual late last evening. A little let down over what it tells me that wasn't in the regular manual provided with the device, but I did learn some things about the physiology of breathing I hadn't been aware of.

What I would have liked to know more about would include comprehensive details about what the different clinical menu option abbreviations actually mean and how they affect the performance of the device during use.

It's been 2-1/2 hours since I arose this morning. I'm still waiting for last night's data to register in MyAir. If lowered PS leaves AHI <5 I'll live with it that way for a few nights before posting graph images from OSCAR here.

BTW: are any particular graphs more meaningful than others? I can manage file sizes for screen captures quite easily while not including less relevant portions will do most to reduce file size.

[spclark]

Pulled SD card, OSCAR says AHI 2.66 for last night so that's relatively stable after change in PS from 4.4 to 3.6. Will drop TiMAX to 3.0 for tonight then review data again tomorrow morning.