Tidal Volume

General Discussion on any topic relating to CPAP and/or Sleep Apnea.
NewToSleepApnea
Posts: 132
Joined: Sat May 09, 2020 6:52 am

Tidal Volume

Post by NewToSleepApnea » Sat Feb 27, 2021 4:50 pm

I know people have said on here before Tidal Volume doesn't really matter (why would they track it tho?)

But whenever I see charts on this forum they never look like mine. It always is hectic and up and down. Does anyone else has tidal volume that looks like this?
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Miss Emerita
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Re: Tidal Volume

Post by Miss Emerita » Sat Feb 27, 2021 9:35 pm

Tidal volume is the amount of air that you move in and out of your lungs in one breath. I don't know why yours is so variable. Mine is high right when I'm settling myself down at the beginning of the night, and it varies some during REM, when I may do some heavier breathing. Some of your variation might have the same explanations, but probably not all. Do you have any awareness of things you're doing that might account for the variability -- sighing, tossing/turning, moving your legs around?
Oscar software is available at https://www.sleepfiles.com/OSCAR/

NewToSleepApnea
Posts: 132
Joined: Sat May 09, 2020 6:52 am

Re: Tidal Volume

Post by NewToSleepApnea » Sun Feb 28, 2021 11:49 am

Most of the graphs I see are high until they get settled like you mentioned. My wife says I don't move much, mostly stay on my side. But it doesn't matter if its a good or bad night - my tidal volume has been erratic. And even on a good night - I have over 50% variable breathing. Every night since starting the CPAP about 9 months ago.

So I get what it is - but what could the problems be if too high or too low or erratic etc?

I don't believe I have ever had a night of steady consistent breathing - even on the two nights I have had 0 AHI recorded. Just seems unusual.

0 AHI Night
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Last night - a very good night.
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Miss Emerita
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Re: Tidal Volume

Post by Miss Emerita » Sun Feb 28, 2021 12:07 pm

Others may have a good answer for you, but I don't. To put your mind at ease, I'd recommend that you talk with your doctor about this.
Oscar software is available at https://www.sleepfiles.com/OSCAR/

rick blaine
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Re: Tidal Volume

Post by rick blaine » Sun Feb 28, 2021 1:06 pm

Hi NewToSleepApnea,

You don't say what height you are, or what build (broad/ big vs slim/ small) or where you come on the farmer-hunter 'scale' (long body, short legs vs short body, long legs). The taller you are, and the bigger the chest, the greater the total lung capacity.

And from that number, one can make suggestions about 'typical' tidal volume, resp rate, and minute vent.

The average healthy young male of 5' 8" (1.72m) has a total lung volume of about 6 litres and with that, you can expect – while awake and at rest – a tv of 500cc, a resp rate of 12 bpm, and a minute vent (the amount of air breathed in and out in one minute) of 6 litres.

While asleep, you have a median tv of 520 cc, a resp rate of 18+, and a median minute vent of 9.25. These numbers are all higher than average. And that's while you are not doing anything.

Which means – if we combine those numbers with the O2 chart – that you are getting enough oxygen – but you seem to be having to work harder than the average male to get it.

You could, as Miss Emerita suggests, ask your doctor if there is any reason why that is.

NewToSleepApnea
Posts: 132
Joined: Sat May 09, 2020 6:52 am

Re: Tidal Volume

Post by NewToSleepApnea » Sun Feb 28, 2021 1:26 pm

Thanks for the replies! Man, the board is great.

I’m a larger build. Played college football. 6 feet 245lbs currently. Working on losing more. Played at 285. So from what you said it makes sense my numbers would be higher. Doesn’t explain the erratic up and downs though.

I will mention it to my doctor but like most people’s experience - as long as my AHI is under 5 - they say it’s all good.