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Exhale Static SaO2 data

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Well-Known Member
Jan 21, 2004
I did some exhale statics with Walrus the other day and got the following data from an exhale static (with reverse packing).

There are two heart rate spikes in the prep breathe up that correspond with the two pack stretches I did. The strange thing is the drop in SaO2 that lines up with them.

....anyone got ideas about what is going on here ?( I was using an earlobe sensor on a ohmeda 3700 pulse oximeter)


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Maybe the pack stretches cause a decrease in blood flow to the extremities, which causes the SaO2 measured at the earlobe to fall.

just an idea

i think the packing must reduce the flow of blood to your head by putting pressure on an artery (aorta i think?). presumably this would reduce the SaO2 in your head. amazing how high your HR goes during packing.
My HR also goes very high during packing, but I have got more used to it now, so the effect is less.
Yeah my heart rate really does soar but Wal's HR broke 200BPM doing the same thing but he didn't have the drop in SaO2 that I did....and he packs 3L compared with my 1.5L.

Maybe the increased heart rate is an attempt to compensate for the reduced blood flow caused by pressure on the heart. This could be why it stops the drop in SaO2.

200BPM is a lot! I haven't measured my HR during packing, but it probably isn't that high, because my max heart rate is about 184.

The drop in HR after the exhale is really quick but interestingly does not seem to last very long
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