Need help configuring my new Bipap to deal with inspiratory flow reductions

[sventory]

Hi all, it was recommended by this great board to try BiPap for my flow limitations that were obviously occuring on just CPAP. Since the high pressure of CPAP alone with only 3 PS was difficult to deal with. I got a used BiPap VAuto.  Previous discussions: http://www.apneaboard.com/forums/Thread-...piralogist

I have only tried it sitting while watching TV for 40 minutes with the following settings:
Max IPAP: 15,
Min EPAP: 8
PS: 7
TI MAX: 3.5seconds
TI MIN: .5seconds
Cycle: Very High
Trigger: Medium

When using it with this, I noticed I didn't feel like I could get a big deep enough breath, possibly because of the inspiration resistance, I could feel the machine switch to exhale pressure before it felt like my inspiration was completed. So maybe the machine was thinking I was done inhaling when the resistance slowed down the airflow? Either way, after doing it for 20 minutes it actually made my heart feel weird, it wasn't pumping faster, but felt like it was pumping harder, definitely abnormal pumping. Perhaps from all the shallow breaths? What can I do here to make this work better?

[Sleeprider]

That is a high PS and long TiMax. First, I would not judge the "feeling" of the machine from trying it while awake, instead, be guided by the data. Assuming this is your first try at bilevel, I recommend you try some more conventional settings. Unless you KNOW you need something else, start with PS 4.0, Ti Max 2.0, Cycle medium. I would guess the biggest problem with your test was the very high cycle, which will switch to EPAP at the slightest decrease in flow. Since you are trying to treat flow limits, this was probably the wrong setting. You may end up,with more sensitive trigger and less sensitive cycle, but let the data take you there, rather than a preemptive guess.

[sventory]

Okay I was just going off what someone said on the other site for what worked for them. High TI Max so it didn't feel like the machine was "rushing" their breathing, since I kinda felt that too.

If my APAP settings were 12-15 with EPR3, what emulates that on bipap? Still unsure quite the min/max/PS emulate that.

[Walla Walla]

The cycle setting of very high is what is causing the inhale to feel cutted off. Set your cycle to med which is the default setting. If you need more time than set it to low.

[sventory]

I get that, but what about the pressure numbers? Thanks as always Sleep and Walla.

[Walla Walla]

Your pressure settings are good to start except for the Pressure Support. Like Sleeprider mentioned set that to 4cm and see how it goes.

[sventory]

Okay. what does that mean? If my max inhale is 15, does it start at 11 if PS 4? ANd if my min EPAP is 8, is that where it starts? or start at 12?

[Walla Walla]

Your starting inhale pressure will start at 12cm and Exhale will be at 8cm. and the pressure can increase up to 15cm inhale and 11cm exhale. After you try that you can adjust as needed.

[Sleeprider]

You will achieve better results by using a conservative titration and problem solving approach, rather than radical settings someone on the internet uses. We can take the time to do this right, and it will fit your individual needs. Be patient, you have the right tool to get there.