New User - Help With BIPAP Settings

[Microm]

I did an at home WatchPAT study through Lofta showing an AHI of 2 (6 in REM) and RDI of 12 (16 in REM) due to otherwise unexplained fatigue and cognitive issues. This seems to be indicative of mild REM-dominant apnea and possibly UARS. I bought a used BIPAP to try, and have used it consistently for the past 4 weeks. My mental clarity, alertness, and exercise tolerance have definitely improved though I almost never wake up feeling refreshed. It also appears that in the past week some of the issues have been coming back, on and off.

The strange thing I have noticed is that running lower pressures, such as EPAP 4 with PS 3, produces low events, and does not cause the machine to automatically raise the pressure much. Increasing EPAP and/or PS seems to increase events, as well as cause the machine to drive the pressures higher during the night. See the two attachments.

I also attached a section showing some flow limitations in the graph. These seem to come and go during the night, likely due to the stage of sleep. It appears clearing them would require higher PS settings, just curious why the events seem to increase when I do so.

Would also like advice on the overall settings and titration going forward. Much appreciated.

[Sleeprider]

There are no prizes for using pressure above what is comfortable and effective for you. Your therapy looks great at the lower pressure and I don’t see any advantage at this time to use a higher pressure or analyze fine detail of the flow rate looking for issues. Pressure 4-9 at PS 3 seems about right. You can experiment wit PS 3.4 if you want, but the bottom line is efficacy and comfort, and you already have that.

[Microm]

There are no prizes for using pressure above what is comfortable and effective for you. Your therapy looks great at the lower pressure and I don’t see any advantage at this time to use a higher pressure or analyze fine detail of the flow rate looking for issues.  Pressure 4-9 at PS 3 seems about right. You can experiment wit PS 3.4 if you want, but the bottom line is efficacy and comfort, and you already have that.

Yeah I am certainly not looking to increase pressure for the sake of it. Just trying to see if a bump will improve how I feel, especially in the morning, if this is indeed some UARS type of flow limitation problem.

My main curiosity is why does increasing the pressure seem to worsen my events? I understand how it could worsen comfort, or increase leaks, but I don't understand how it could increase events, even if it might not be beneficial. 

Also, when you said 4-9 at PS 3, do you mean EPAP 4, PS 3, and IPAP max at 9? Sorry, I am new.

Thank you.

[Sleeprider]

4-9 at PS 3 is EPAP min 4.0, Maximum pressure 9.0 or a pressure range if 7/4 to 9/6. Higher pressure may increase expiratory resistance in your case. Individuals respond to pressure differently, and you have no clinical need for higher pressure, so based on your own findings, the lower pressure seems fine. With UARS you will more likely benefit from small increases in PS than minimum pressure, and that is why I suggested you experiment with PS 3.4. As with all titration, it is trial and error, and it's like visiting the eye doctor...Is this better, or this; this or this? That pretty well sums up the science of sleep medicine.

[Microm]

Gotcha. So, going forward I should leave EPAP alone at 4, and only play around with higher PS to see if it improves things. I also assume if I feel a bit starved at 7.X IPAP, I should just increase PS, and not EPAP to get a bit air in?

[SarcasticDave94]

In that scenario of air starvation, that may be where EPAP min increase would benefit. This is your "if you need it" scenario. My reasoning, EPAP min addresses the absolute minimum pressure you can be presented to the mask, which is exactly where air starvation would be based off of. So bumping up from EPAP Min 4 to 4.x should begin addressing this.