hello I just finished my externship for Medical Assistant...I am with u I 
don't understand those stupid things either...We did tredmill stress tests on 
elderly patients with heart problems..they were out of breath, could hardly 
talk to you, while on a tredmill...BUT, their pulse-ox said they were at a 
95%oxygen..it is "suppose" to be for the whole body.  Personally I have found 
that just putting that on their finger is not a good judge.  The pulse-ox has 
a habit of falling off and not making a good connection.  So, I really don't 
know the answer to your question either...Hope I didn't confuse u anymore :)
If u ever find out the answer pass it along to me too will ya?
thanks 
gina
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