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07-02-2025, 02:03 PM (This post was last modified: 07-02-2025, 02:04 PM by roseandpeak.)
Help with Oscar data - tons of spikes on flow rate
Hi everyone, I've been on CPAP for 2 years and use it religiously. My pressure settings for a long time were 5-10 (no EPR). But recently, in response to persistent fatigue, I realized I could change the settings and tried something new - higher pressure, minimum around 9 and max around 12. I've been diagnosed with UARS and then sleep apnea (untreated AHI 8.5). The last few days I feel a bunch better on higher pressure, but I'm having bad dry mouth, some more full awakenings in the night. (Yes, despite feeling better in general!)
Trying to optimize my settings, I have a couple questions.
- why is my flow rate *so* spiky throughout the night? I'm posting some data from one representative nights (June 4, before I increased my pressure settings). I'll add another comment with three more attachments for after I increased my pressure settings.
- how can I calculate the optimal pressure for myself?
- should I use EPR?
Thank you so much!
Here are the screenshots from after I increased my pressure settings. Thank you for any help you can provide!!
07-04-2025, 10:59 AM (This post was last modified: 07-04-2025, 11:00 AM by ejbpesca. Edited 1 time in total.)
RE: Help with Oscar data - tons of spikes on flow rate
Rose and Peak wrote:
"- how can I calculate the optimal pressure for myself?
- should I use EPR?"
What most do to find the optimal Min pressure is experiment with pressure changes. Most often, those changes are increases. It can be best to make them in small increments of .2 or .4. Sometimes the Med pressure under Statistics is used as a reference for Min pressure and 95% for Max. These figures change over time. It is best to observe results for a time (maybe a week) before making more changes to the pressure. CAs can be a temporary result of pressure changes.
EPR is a personal preference. Some suggest EPR 3 to reduce Flow Limitations. Others turn it off because they feel it diminishes the efficacy of therapy. Turning on EPR can also cause CAs that are hopefully temporary. Trying EPR at 1, 2, and three will show if you should use EPR. It may help with UARS. EPR was first intended as a comfort feature, not a therapeutic one.
UARS may be better served by a Bi-Level PAP machine.
Your settings of 5-10 are unusually low. Some feel 7 is the lowest Min pressure for adults. You can allow Max to go to 20 while establishing your best settings.
If Max is set to 20, goes there and remains, that is a sign of apneas and flow limitations that PAP therapy cannot treat. When apneas and flow limitations are caused by sleeping in a position that pinches the airway, air pressure does not work to resolve the problem. This is called chin tucking. If you suspect you may chin tuck, there are many threads and articles here about it, as well as on YouTube.
Your < 1.00 AHIs are as good as it gets. Some go for 0.00, but I feel that is not realistic.
I only give suggestions from experience as a fellow CPAP user, not professional advice. My suggestions are for consideration, they are not definitive instructions.
RE: Help with Oscar data - tons of spikes on flow rate
Thank you so much for your help! You don’t think the spikes on the flow rate are a problem? I have heard they can be sighs, so not a problem, but I’ve also heard that ideal treatment will show a consistent flat flow rate.
RE: Help with Oscar data - tons of spikes on flow rate
The ideal treatment will show a slightly consistent flat flow rate with occasional sighs, like we have during the day. Also there will be repeating erratic breathing during REM sleep every 60 - 90 minutes or so..
Hide the calendar, so the device settings show.
Also replace the snore chart with the Tidal Volume chart. You may see little peaks in the Tida Chart that occur during REM sleep. Like after midnoight and after 1:15
Your flow limits are a bit high, consider trying EPR of 1 or 2 for a few nights.
Also, like EJ said, you minimum is way too low, especially if you are going to try EPR.
Try a minimum of 7 or 8 cm.
RE: Help with Oscar data - tons of spikes on flow rate
Please turn off Calendar by deselecting it under View.
You have such a low AHI and exceedingly low Min pressure setting. If it were me, I would want another sleep study to make sure pathological sleep apnea is present.
Dry mouth usually comes from mouth breathing within a full-face mask. You don't have a Leak Rate or Large Leak problem that may show up due to mouth breathing with a nasal mask, so it is curious how you may be mouth breathing that produces dry mouth and getting great therapy. Have you considered another sleep study to make sure you have sleep apnea?
As you raise the Min pressure, you may find CAs appearing, which in turn raises the AHI. This is very common, and with time, they diminish.
Flow Limitations and UARS are interesting topics that need to be researched further. My four in-lab sleep studies gave no attention to Flow Limitations. My Flow Limitations and breath wave shapes show UARS is present. Perhaps the higher Min pressure you try will reduce UARS symptoms and round out your breathwaves in Flow Rate.
Wiki at the top of this page has information on UARS.
I only give suggestions from experience as a fellow CPAP user, not professional advice. My suggestions are for consideration, they are not definitive instructions.
