CPAP Pressure vs Bipap

[nadprok]

I have been on Bipap for 3 years now . When I started I had a sleep study but no titration study . My AHI numbers have been very good averaging under 1.5 for the last year. However I have been having problems with sleep fragmentation . My sleep doctor recently decided to have me do a titration study to try and determine why my sleep was so fragmented . My problem is that the therapist used straight CPAP for the study . She said that is what the doctor ordered even though I am using a Bipap .
With the CPAP titration study my best numbers were at a pressure of 10 . I had 0 hypopneas , 0 rera , 0 centrals , and 9 PLM . 
In the report the doctor stated "CPAP pressure of 10 are necessary to control sleep disordered breathing in non-REM sleep but pressures higher than 11 are clearly necessary in REM sleep ."

My question is what Bipap pressure would equate to the 10 CPAP pressure ?  I was not told what pressures to use with Bipap . I asked the doctor if I should switch to CPAP and he said no .

[Hojo]

BiPAP is basically CPAP except when you exhale, the pressure drops so that you can exhale more easily...some folks (me included) do not tolerate a (high) pressure all the time.

I have to wonder why they did a sleep study starting off at 10; I thought they started off at 5 and went up on the pressure if you have obstructive events.  In your case you didn't have any OA events at 10 so I see no reason to go up to clear any obstructions.  The PLM events, isn't that periodic limb movements.

If you can post your sleep study and sleepyhead data, more information can be obtained and better tips provided.

[nadprok]

They actually used 4 different pressures . Starting at 8 I had 5 Hypopneas and 8 RERA for a RDI of 24
                                                            Then at pressure of 9 I had 6 RERA for an RDI of 19.9
                                                            Then at pressure of 10 I had 0 events for an RDI of 0
                                                             Then at pressure of 11 I had 1 mixed apnea, 3 hypopneas and 8 RERA for an RDI of 16.5

This is all based on only 2 hours of sleep time as I slept very poorly .

[Hojo]

Gottcha, then if they started lower and moved up, they are saying that 10 would be the minimum pressure needed to overcome OA events and so I would just stick with 10 and if you feel better with BiPAP, then by all means, stick with it.  Of course, posting Sleepyhead results here would help in giving you better recommendations.

[Ron AKA]

My question is what Bipap pressure would equate to the 10 CPAP pressure ?  I was not told what pressures to use with Bipap . I asked the doctor if I should switch to CPAP and he said no .

I use an AirSense 10, not a BiPap, but if I had to guess I would suggest moving your EPAP minimum from 9 to 10 cm, and possibly your IPAP maximum from 15 to 16, while leaving your pressure support as is. 

That said, is there a reason you are using a BiPap instead of a standard APAP? Your pressure settings seems to be well within APAP capability.

This seems like a lot of trouble to go to, just to increase your treatment pressure by 1 cm. Do you have any SleepyHead daily screen shots that you can post? That may give a lot better idea what may be waking you up.

[Sleeprider]

Your recommendation is based on just over 1-hour of sleep at the suggested pressure. Truth is, there is no difference between the 9, to 11 pressures you were tested at other than your sleep stage and the recorded results. The test is complete B.S. and you should have see it coming. We could have given you a better analysis based on # Sleepyhead. Maybe you should download the software and give us a shot.

Your test just downgraded your machine and therapy. Good luck with getting better results with the "PRO" recommendation. "I can use 20 minutes of a technician's observations and do better than your years of therapy data"....right?

[nadprok]

Thanks everyone for your replies .

I do have Sleepyhead software so I am attaching some screenshots from last night. 


[attachment=5509] [attachment=5510][attachment=5509][attachment=5512][attachment=5513]

[Sleeprider]

Your settings are 8.8 to 15.0 with PS 2.4 in Vauto mode. Unusual settings, but I'm not judging. Your therapy was in 4 sessions on April 21. Somehow with 5 attachments you have managed to exclude the events and AHI, but it seems most events are CA with a few CA events. Based on teh close-ups of the flow rate, I think you were awake on many of the CA events. You appear to awaken and discontinue therapy every time the pressure changes. This isn't a lot to go on, but it seems that CPAP pressure in the range suggested by the sleep study might be pretty good for you. CPAP pressure would avoid the CA events by eliminating EPR, and without pressure changes, you might sleep better.

Take a look at the link in my signature on organizing your Sleepyhead charts, and lets look at a couple different days.

[nadprok]

Thanks for your reply Sleeprider . My events are almost all centrals . I don't get any obstructive apneas, maybe 1 a month . I get 1 or 2 hypopneas each night  and that is about all . 

Are you suggesting that I would be better off in CPAP mode ? The reason I am on Bipap is because I failed CPAP . I couldn't tolerate the single pressure .
The settings I am using are settings that I slowly kept changing on my own until I got to an acceptable AHI . With those settings my AHI is under 1.5 pretty well every night .

I will post more charts in a day or two and will organize them the way you suggest .

[Ron AKA]

Based on your titration study and the SH screen shots, I think I would set the EPAP at 10 cm, set the Pressure Support to zero, and leave the IPAP max at 15. Try that and see what happens. It seems like of what you have shown, that pressure is only being driven up by flow limitations, not OA or H. If those settings work OK, then I would start lowering the EPAP in steps until you start to see OA events or H. If pressure increases due to flow limitation become a problem and wake you up, then you may have to stop lowering, and go back up to the previous step.