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Oxygen Saturation

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Deeper Blue Hypoxyphiliac
Oct 24, 2002
Has anyone had a chance to hook themselves up to an oxygen saturation meter before?

I jsut got my wisdom teeth out, and the nurses had to check my pulse/SO2% every couple of hours afterwards. One thing I noticed - for most of the day, my saturation was at 95%, and when I woke up this morning, it was at 93%. Why wouldn't it be at 100%? Would this affect my statics or diving? I remember seeing graphs of peoples oxygen saturation over time during apnea, and I thought it took like minutes to get from 100% to 93%?
Your O2 saturation will normally show up as 95-98%. In theory you can't even reach 100% saturation without breathing pure oxygen.

I'm often at 95%, and then one or two deep breaths puts me at 98%.

Eric Fattah
BC, Canada
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Ah ok sweet, I thought I might've been broken - cheers :)
Originally posted by loopy
One thing I noticed - for most of the day, my saturation was at 95%, and when I woke up this morning, it was at 93%. Why wouldn't it be at 100%?

Is that drop in saturation a sleep induced drop or should Brad be getting checked for sleep apnea?

He could be pulling 8 minute breath-holds while asleep and never know...:D
Correct me if I'm wrong but I reckon maybe cause I was breathing fairly shallow, the rest of that was something like CO2, CO or some other exotic gas... the other alternative I thought was maybe I still had a little bit of anesthetic in blood stream
Loopy, I have a pulse oximeter at home and was surprised at the results when testing during static apnea. The saturation level did not begin to drop until long after the struggle phase. But when it began to drop, it dropped quickly. It was very difficult for me to maintain the breath hold into the mid 80's. I'm not sure if I learned anything I could apply to diving from those tests, but it was interesting nonetheless.

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It also depends on your oximeter. I was using an older Ohmeda 3700, which was very inaccurate when the SaO2 dropped below 70%, and I even finished a few breath-holds at 11%, which was obviously wrong. Now I'm using an ultra modern Ohmeda 3900P, and the lowest I can get to without a samba is around 44%, which agrees with physiological models.

Eric Fattah
BC, Canada
Do you know at what % blackout tends to occur? Or is the variation to large to generalize?

During test on how people react to low oxygen they sometimes put up safetynargins. In one test I was involved in we where not allowed to hold our breath beyond 50% (This is the blood measured at the ear - the oxygen level in the blood returning to the heart can be lower).

I did other test by my own initiative (with state of the art equipment) and went as low as 35% but I was pretty much gone then.
You can read about it here: http://www.webvideo.nu/freediving/features/breathhold.html

Cebaztian, Just looked at your link and the trends shown in the graph are very interesting to me as a begginer. Can anyone expand on the analysis in the conclusions.

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