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[Diagnosis] ? about flow rate graph-multiple discrepancies
? about flow rate graph-multiple discrepancies
When you expand the flow graph and see discrepancies in the normal flow of breathing does that mean arousals have occurred?  My Flow Rate is almost all discrepancies with very little normal flow of breathing.  What should be done about this.
full graph
60 min section
30 min section
60 sec section
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RE: ? about flow rate graph-multiple discrepancies
For viewing the flow rate on your ASV, the best graphic display is about a 2-minute section showing the Flow-rate, pressure, mask pressure and flow limitation. This allows us to see the interaction of respiratory flow with the inputs from the ASV. It is particularly difficult to associate flow rate changes in ASV with sleep disruption because of the number of variables that may occur on a breath by breath basis, but we can see where the machine is triggering higher pressure support due to a possible central or hypopnea that is being treated and prevented. I would avoid looking closely at sections near the beginning and end of therapy. Your 60 second segment is shortly after sleep begins, and I would suspect that with IPAP pressure at 19 cm that these breaths are machine induced. Again, the mask pressure provides a better representation of the machine pressures, and a 2-minute segment is ideal. Please also include the information in the left column with respiratory and machine statistics so we know what your settings are.

Haley, welcome to the Apnea Board forums.
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RE: ? about flow rate graph-multiple discrepancies
Hope these help, approx. 2 minute sections
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RE: ? about flow rate graph-multiple discrepancies
Haley, your charts are excellent. Thanks for rearranging. First, you have extremely low AHI using the ASV. It is preventing any obstructive or central apnea and just a few hypopnea are being recorded. Your machine is in fixed ASV mode which means you don't get auto-adjusting EPAP pressure which could keep your pressure lower. Your minimum pressure support is 6.0 which is on the high side and probably makes central apnea worse than a lower minimum PS like 3.0. Most of the flow charts you showed feature flow limitation with flattened peaks and even some snores like 02:12:35. Your tidal volume is relatively high for a female, but with the low respiration rate of 10.8 you need the volume to provide an adequate minute vent.

Let's get back to your original question of why you have such uneven flow or rate of respiration. Very simply put, we can't really tell why breathing is uneven. your breathing rate is relatively slow. Would you be interested in trying some different settings to see if they are more comfortable and work better for you? I think you would experience smoother breathing if your minimum pressure support as lower because you would probably need fewer machine triggered breaths, and the contrast in those machine triggered breaths would be higher. Your current PS min is 6.0 cm, and most of your breaths, the machine is getting the job done with 8-cm. I'd like to cut you back to 2 or 3 cm of minimum PS. With your current EPAP at 7.0 and minimum PS of 6.0, your machine is producing 13.0/7.0 as a baseline. My suggestion would be to use ASVauto mode with EPAP min 5.0, and PS min 3.0. Everything else would be the same. The machine will automatically increase EPAP pressure as needed, and will provide pressure support as needed to prevent events, but the minimum would be 8.0/5.0. Finally, is this low respiration normal for you, or have you been diagnosed with restricted breathing or COPD?
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RE: ? about flow rate graph-multiple discrepancies
Thank you so much for all the information, I am going to try your recommendations on the machine settings tonight. Would they be able to tell about the restricted breathing and/or COPD at the sleep studies I've had?  I had one without a mask and 2 with a mask and no one mentioned restricted breathing or COPD. I will be seeing the sleep neurologist with my clinic in two weeks and will definitely ask him about it.
Do the discrepencies in my flow rate graph signal arousals? If not, is there a way to get an idea of how many arousals I have during the night since I have PLMD?
Thanks again for the taking the time and all the help.
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RE: ? about flow rate graph-multiple discrepancies

I reset the settings as you suggested and am including some attachments of my sleep report.  I think everything we reset looks better.
Old settings all night overview
New settings all night overview
some 2-3 minute shots with the new settings

My sleep center therapist says that their program does not show flow limits or flow rates - isn't that something important?
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