CPAP Pressure vs Bipap

[Sleeprider]

I completely disagree with Ron AKA, and I'll just leave it at that other than recall Walla once said Ron never saw a pressure he didn't want to raise.

Nadprok, your events appear to be all central, and you don't tolerate pressure increases, which don't do you any good since there is no obstruction occurring. I think you do pretty good with the pressure support and starting pressure of 8.8 EPAP with PS 2.4. I don't propose CPAP, but I do think fixed bilevel (BiPAP-S) is perhaps going to be more comfortable, and may help avoid the therapy breaks. To get those settings, just leave EPAP min at 8.8 and set EPAP max at 8.8 and leave PS at 2.4. Alternatively, change mode to VPAP-S and set EPAP to 8.8 and IPAP to 11.2. This will keep pressure constant, but preserve the feeling of different EPAP and IPAP pressure.

If anything, we will watch your results for an opportunity to REDUCE pressure.

[Ron AKA]

If anything, we will watch your results for an opportunity to REDUCE pressure.

Actually, to be accurate, my suggestion was to REDUCE the pressure. Currently median IPAP is at 11.5 cm, and EPAP at 9 cm. If you set EPAP at 10 cm, and REDUCE pressure support to 0, then the maximum treatment pressure is REDUCED by 1.5 cm. This EPAP setting has the potential to address the flow limitation before it causes arousal and as a result gain a better sleep. And at the same time maximum mask pressure is REDUCED which may improve sleep quality too. And, I suggested that if it worked at that setting, there may be a potential to further REDUCE EPAP in small steps.

What this ignores however is the reason that a BiPAP machine was considered necessary in the first place, and I haven't seen it, although there may be one, that requires the pressure support to be restored.

[Sleeprider]

Bilevel is often prescribed and allowed when a patient does not tolerate CPAP. Most likely she was started at fixed pressure on a machine that could not provide EPR, and found she was unable to sleep. The Resmed Airsense CPAPs can produce up to 3-cm of pressure difference between IPAP and EPAP which will increase comfort, although it does not have the control to simulate pressure support between 1, 2 or 3 cm, or higher. I agree, it seems unusual that bilevel is used at these pressures and generally low PS, but I think it gives us some flexibility we would not have with CPAP.

[nadprok]

OK , Sleeprider and Ron AKA thanks for your input . I have set my bipap to S mode and set  EPAP at 8.8 and IPAP  at 11.2 . I will try those settings tonight and see how I make out . 

Incidentally Sleeprider  in your last reply you refer to me as She .  I am a He and not a She .

[Sleeprider]

I believe in equal opportunity apnea

In S more be sure to enable Easy Breathe if available

[nadprok]

Sleeprider , last night I set my bipap in S mode and set my EPAP at 8.8 and my EPAP at 11.2 and 0 pressure support . The result for last night was an AHI of 1.4 which is within the range I have been having , usually 1.5 or less . All of the events were Centrals . I believe I may have slept  a bit better.

I notice that my flow limitations were 0.11 for the whole night . I have not had any flow limitations greater than 0.03 in the past . I am curious to know why the big increase .

I would also like to mention that the machine settings shown in the left sidebar are incorrect . I find that any changes to machine settings are not reflected in the left sidebar until the second day . Why, I don't know .

I am attaching some charts from last night .

What do you suggest for tonight ? Keep the same settings or do you have other ideas ?

Thanks for all your help .

[attachment=5536] [attachment=5537] [attachment=5538]  [attachment=5539]

[Sleeprider]

Being comfortable is the most important matter because you are effectively treated. If I was trying to reduce CA events, and had no obstructive events, I would reduce pressure support, or the IPAP over EPAP difference. You are at 11.2 over 8.8, so my next move would be 11.0 over 8.8. Move IPAP pressure slowly downward and see if the CA events are reduced. If your need the 2.4 PS for comfort, the I would reduce both IPAP and EPAP in small increments (11.2/8.8, 11.0/8.6, 10.8/8.4) until obstructive events occur.

[Ron AKA]

I think you have three issues to resolve in your setup.

1. What EPAP pressure do you need to limit the number of OA and H events? Based on one nights result it seems 8.8 is more than enough. However what will it be over several nights? You can only find out through trial and error.

2. Do you benefit from Pressure Support? Again trial and error is about the only way to find out. After you have settled on an EPAP you may want to do some reductions to see what happens.

3. Last in S mode you essentially have a CPAP machine with adjustable Pressure Support. If you determine in step 2 that you don't benefit from Pressure Support then you really do have a basic CPAP machine again. What you may find out is that the EPAP pressure you need varies a bit over time. If that is the case you may want to consider going back to the VAuto mode, and allow the machine to adjust the EPAP somewhat, so you can cover that range of EPAP needs.

[nadprok]

Sleeprider and Ron AKA I thank you for your advice . You are a great help . I will change my settings for tonight to 11 and 8.8 and see what happens .