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+--- Thread: Very high tidal volume then BND (/Thread-Very-high-tidal-volume-then-BND)
Very high tidal volume then BND - elliotg - 02-17-2020
I had a very strange period last night using my Dreamstation Go Auto. First I got a very brief impossibly high tidal volume (over 6000 when normally around 300). Then a few seconds later flow rate goes to zero. This was followed by 14 pressure pulses. And then about 4 minutes of BND. At the end of this everything goes back to normal. I do not believe I I stopped breathing for 4 minutes! I note the pressure reading seemed unaffected by whatever was happening. No other events around this time.
Any idea what all this means?
RE: Very high tidal volume then BND - elliotg - 02-17-2020
I thought I should add some Oscar screenshots
RE: Very high tidal volume then BND - Gideon - 02-18-2020
Your OSCAR screenshots are missing vital stats found in the left sidebar. This is important since your tidal volume is low at 300 and should be investigated, that is unless your weight is something close to 43 kg per common formulas.
That BND looks like the machine stopped recording, a glitch when it starts and picks up with 'normal' breathing when it resumes. Try a new SD card.
RE: Very high tidal volume then BND - elliotg - 02-19-2020
Thanks for your reply. I will get a new SD card and see how that goes.
But your comment about tidal volume is worrying. You are right about it being at 300 - I have attached the missing data. This is not an isolated result, I have looked through a a range of daily data and this figure does not vary very much. Also note that this results are from my travel CPAP. Most of the time I use a REsmed machine (S9 auto). Typically the median averages out at 320 - not much higher.
My weight is very much above 43 kg - closer to 65! So I am concerned about this result, particularly given that it is not machine specific being similar across both quite different systems. Can you give me some links with information about this so I can give my next steps some thought?
The obvious course of action would be to see my sleep specialist but he only looks at Rescan data (and only summary data with that). i notice that this parameter is not one that rescan seems to display.
RE: Very high tidal volume then BND - Gideon - 02-19-2020
Search for tidal volume calculations.
I would discuss it with a breathing specialist, a pulmonologist. Your TV is normal for a smallish female so you could be an outlier.
Based on weight your TV should be 450 +/- (390 - 585)
7ml/kg (6-9) body weight
To me it is a flag to be investigated.
RE: Very high tidal volume then BND - sheepless - 02-19-2020
for my own future reference, isn't tv is based on ideal weight for one's height and gender?