New to CPAP - Need advice!

[avaholic]

The current settings are:


Mode VAUTO
Max IPAP 16
Min EPAP 9.6
PS 4.0
Ti Max 2.5s
Ti Min .06s
Trigger Very High
Cycle Very Low

So is there nothing else I can do to extend the inspiration breath?

[Sleeprider]

You can increase Ti min significantly, just remember it is going to make IPAP persistent for the minimum duration you set. We sometimes use that for individuals that have a wavering inspiratory breath to avoid the machine cycling to EPAP before they are ready. A setting of 1.0-1.2 is not unheard of, but I would work up from 0.8.

[avaholic]

Well... I upped the Ti Min value last night. 

Prior to going to bed, I tested .08, 1.0, and 1.2 while Ti Max was unchanged at 2.5. I perceived that 1.0 gave me what I considered to be a full inspiratory breath so that is what I used for the full night, 1.0.

Monday night prior to changing Ti Min, I did not sleep very well and was also up 2 times during the middle of the night.
[attachment=9559]

Looking at my graph this morning I was shocked to see a lot more flow limitation where it was basically down to none before. At 3:30 am I woke up and remember looking at my watch, obviously because I was experiencing a cluster of OA's that started around 3:10 am. Why does increasing Ti Min produce more FL? Were the OA's and FL a result of this Ti Min change? Also of note is the IPAP pressure, usually on nights where I don't feel as rested I find that the pressure has spiked all the way to 16 several times during the night like it did last night. On Monday, the highest it got was 15.30. This past Thurs where I only recorded one CA, IPAP did hit 16 but for only one second. Last night it hit 16 and hovered around 16 for several seconds 7 times during the night.
Tuesday
[attachment=9560]
[attachment=9558]

I guess I can go back to .05-.06 Ti Min but having my inspiratory breath cut off when I wasn't finished breathing in is a bit uncomfortable. Maybe its just while I'm falling asleep and its actually fine while I'm asleep...  ??

Man there is so much to all this stuff, I just want some consistency. 

Thanks!

[Sleeprider]

The OA cluster looks positional. The increase in flow limitations comes from your inspiratory effort falling off before 1-second, so the machine does not cycle to EPAP due to your settings, but continues to provide IPAP. This results in a slowing positive flow and the measurement of a flow limitation. In this case it is not due to upper airway resistance, but is the machine completing a breath that you are not working to make. I'm sure you will see this flow limitation in a zoomed in view.

[avaholic]

So is my assumption correct that my perception of not taking a full inspiratory breath while going to sleep changes when I'm actually asleep? 

Should I change the Ti Min back to .05/.06?

Any idea why I have those IPAP pressure spikes? Should I up the IPAP value?

5 min snip
[attachment=9562]

[Sleeprider]

So is my assumption correct that my perception of not taking a full inspiratory breath while going to sleep changes when I'm actually asleep? 

Should I change the Ti Min back to .05/.06?

Any idea why I have those IPAP pressure spikes? Should I up the IPAP value?

5 min snip

There are no IPAP pressure spikes. That chart is your breathing flow rate, not the mask pressure.  We can see the steady breathing of normal sleep transitions to chaotic respiration of a positional flow restriction and possible arousal. The inspiratory spikes are sharp inhales typical of recovery breathing followed by strong flow limitations interspersed with recovery breaths.  As far as changing settings, go with whatever feels good. Ti min ensures that IPAP is held at least x.x seconds, and Ti Max ensures it won't be maintained longer than x.x seconds.  The Vauto follows your respiratory lead and will maintain IPAP as long as you are continuing to make the effort to breathe up to the Ti Max, when it will cycle.  When your breathing is uneven or weak, IPAP may cutoff sooner than you are ready, and that is where Ti Min can hold IPAP, even if your inspiratory flow drops before the Ti Min is reached.  Most people do pretty well with the default timing, trigger and cycle sensitivity, but the tools are there if you need them.

I think if you're having problems with these settings, then backing off Ti Min slowly is a better idea than using the very short 0.3 default.  Don't make any changes on the basis of the abnormal positional cluster, but how the majority of the night feels.

[avaholic]

Sorry Sleeprider but I don't understand... I think it'll finally click at some point! LOL.

Is the 'Pressure' chart NOT the chart that lists the IPAP and EPAP pressures throughout the night? If you look at Monday night from post #123, the pressure chart does not hit 16 at all. On Tuesday however the Pressure chart hits 16 - 7 different times throughout the night lasting several seconds each. That's why I was asking if I needed to up the IPAP pressure. I thought that the 'Flow Rate' chart was the breathing rate. 

As far as comfort goes, I thought I was much more 'comfortable' last night with the Ti Max raised to 1.0. but the full night graph shows differently with all those flow limitations, doesn't it? Maybe my breathing rate slows when I finally do get to sleep and the perceived cut-off was not a cut-off at all.

I'd prefer to get back to breathing normally if that is indeed what was happening when the Ti Min was set to .05/.06.

I am happy to keep experimenting with different settings as I'm on vacation til Jan 2nd.

[Sleeprider]

You're right, I was mainly addressing the flow rate chart and was not concerned with pressure which is steady at 14.4/10.4 through that segment. Your current range of 13/9 to 16/12 looks pretty good to me. Your OA is coming in clusters which correspond to the maximum pressure. I don't think higher pressure is all that helpful in that circumstance, but you know your tolerance for pressure. If you allow it a higher IPAP range, then it will increase to the maximum setting during any obstructive cluster.

[avaholic]

I'm still trying to tweak my settings for optimal therapy. 

Last night I upped the Max IPAP to 16.4. I also lowered Ti Min back to .05 thinking that this would even out my flow limitations again. I think Saturday's chart show that FLs were definitely lower but the inhalation breath is very uncomfortable as its cut off mid-breath. The IPAP pressure throughout last night never maxed out. I also notice on most nights that the median EPAP is usually around 10. I did not sleep all that well Saturday but I didn't wake up during the middle of the night. 

Would raising the EPAP Min help? 
Should I go back to Ti Min .08 even thought the flow limitations are not as low/even? 
What about adding more pressure support?  

UGH.

Thanks!

Thursday
Ti Min .08
[attachment=9598]

Friday
Ti Min .06
[attachment=9599]

Saturday
Ti Min .05 and IPAP Max 16.4
[attachment=9600]

[avaholic]

I raised EPAP Min to 9.8 and reverted back to Ti Min .08. This Ti Min setting makes breathing in much more comfortable. 

IMHO, the flow limitation chart looks better, right? Refer to the above post for the past few days.

I think I slept better last night as well.

Should I touch pressure support?
Any other thoughts or suggestions? 

Thanks!

Sunday
[attachment=9622]