+- Apnea Board Forum - CPAP | Sleep Apnea (https://www.apneaboard.com/forums)
+-- Forum: Public Area (https://www.apneaboard.com/forums/Forum-Public-Area)
+--- Forum: Main Apnea Board Forum (https://www.apneaboard.com/forums/Forum-Main-Apnea-Board-Forum)
+--- Thread: Looking for help to optimize cpap settings (/Thread-Looking-for-help-to-optimize-cpap-settings)
Looking for help to optimize cpap settings - BadJanitor - 01-09-2021
Hello. I was diagnosed with mild sleep apnea and an AHI of 8 a few months ago. My Dr. recommended a CPAP machine (dreamstation + f20 mask) since I was having issues with daytime brain fog and fatigue. I do feel slightly better with the therapy, but I'm questioning whether it's worth the hassle. On most nights with the machine my AHI ranges from 2-4, which doesn't seem like a huge improvement on paper. I see reports online of people going from an AHI > 50 to < 1, so I'm wondering if there are settings I can optimize further.
My Dr. originally had the pressure range set to 5-20 with C-Flex on 3. I eventually bumped the minimum pressure up to 6 since I felt a little starved for air which made it much better. Looking at my charts, the auto seems to vary between 6 and 7.5. Would it help to turn it up?
My DreamMapper has only ever shown 100% fit, but in my OSCAR data the leak rate seems much higher. I don't actively notice the mask leaking, but some days I wake up with very dry eyes and I wonder if it is related to air somehow.
Anyways, here are a couple recent OSCAR reports. Anything you guys would recommend I change and test out?
(Sorry, couldn't figure out how to turn off VS2)
RE: Looking for help to optimize cpap settings - Sleeprider - 01-09-2021
The Philips Dreamstation Auto is notoriously slow to increase pressure, and tends to respond to events reactively rather than proactively or preventative as we see with Resmed. Your move to increase pressure was a good idea, but you probably need to take it up a bit more. I think for now, move it to 7.0 and turn Flex down to 2. In the image below, we see the inspiratory peaks are extremely flattened and this indicates "flow limitation" or upper airway resistance. This upper airway resistance or flow limitation means it takes more effort to get air in, so inspiration is drawn out and more difficult than it should be. More pressure should help to hold the airway more open, however, again, the Resmed is superior by actually providing an increase in pressure as inhale occurs, rather than just the constant pressure of the Philips. Anyway, you can see that the flow limitation leads to an obstructive apnea and an arousal as indicated by the larger irregular flow and snore, then the machine FINALLY increases pressure twice stopping the events. The idea of increasing minimum pressure is to give your machine more of a head start in preventing these events, and I could see us going to 8.0 to really be effective.
As flow limits are reduced, you will start to feel more of the benefits of your CPAP therapy. When those are present, you will have respiratory effort related arousals (RERA) and this is really hard on your sleep integrity.
RE: Looking for help to optimize cpap settings - BadJanitor - 01-09-2021
Thank you so much! I will make the changes you suggested and see how it goes.
Should I be concerned about the leak rate at all? It seems so much lower on other's reports.
RE: Looking for help to optimize cpap settings - Sleeprider - 01-09-2021
Your leak rate is excellent. On Philips machines, Oscar graphs both the total leak and excess leak. As you can see, the excess leak or unintentional leaks are at the bottom of the graph. It looks very good to me.
RE: Looking for help to optimize cpap settings - Phaleronic - 01-09-2021
I had the dreamstation APAP for a year and had the same settings as you did set by the DME, but I adjusted them as you are doing. You don't need the max set to 20, your 90% pressure is much lower than that so I'd drop it down to 15 and boost your min closer to 8 and see how it goes (as sleeprider suggested).
RE: Looking for help to optimize cpap settings - BadJanitor - 01-09-2021
Thanks for looking at the leak rate. I had initially assumed that any leaks = bad, but it makes sense that there would be some intentional leaking/venting.
Quote:You don't need the max set to 20, your 90% pressure is much lower than that so I'd drop it down to 15 and boost your min closer to 8 and see how it goes (as sleeprider suggested).
Thanks for your feedback Phaleronic. Out of curiosity, is there a downside to having the max pressure range set too high if I'm not getting anywhere close to it? Does it negatively affect the algorithms that the machine is using?