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Flow Rate Readings
I'm looking at my SH charts and I see some areas where the flow rate indicator becomes much thinner. Hovering over those areas I find that the figures go into the minus figures, the lowest on last nights readings was -25. I'm not sure what this means. There is a slight increase in leak rate but nothing else stands out. The pressure is reasonably constant and there are no events during this time. Is this something I should look at, is it an indicator of breathing issues?
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you forgot to put the zoomed chart in, it may be a bit of mouth breathing with the nasal mask.
new http://www.apneaboard.com/wiki/index.php...re_success
mask fit http://www.apneaboard.com/wiki/index.php...ask_Primer
From machine or charts for auto-cpap, set the min 1cm below median pressure, or 2cm below 90/95%. max at 20cm for now. Forum will help you fine tune settings
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Negative flow rate occurs on exhale.

(It really isn't negative because the flow generator is always pushing air down the tube. But, the machine finds a numerical average to call zero such that positive is inhale; and negative is exhale.)

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If you right click on the left margin of the flow rate chart, you can select dotted lines, and add a zero line. The zero line is where inhale and exhale cross-over. Below the zero line is exhale and is expressed as negative mL and on the positive side is inhale. in the absence of leaks the total volume/time will be approximately equal. It is normal for time of exhale, including the null flow before inhale to take longer than the inspiration time.
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Here's the image. What I'm talking about happens at about 5:25am

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I think ajack is right. Your breathing looks normal.
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