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Old 03-14-2013
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Default Cyanide and SaO2

In CN poisoning it stops the ETC. So that would cause the SaO2 to increase right?

I think I had a question on it but I cant seem to find it again.

Thanks! =)
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Old 03-15-2013
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Originally Posted by stinson View Post
In CN poisoning it stops the ETC. So that would cause the SaO2 to increase right?

I think I had a question on it but I cant seem to find it again.

Thanks! =)
My understanding of CN is that it has more affinity to hb so it kicks O out of hb ( thus decrease O2 saturation).. But if an o2 binds to hb, CN causes it not to let go ( increase hb affinity to O2) and thus a lt shift in dissociation curve.. 3rd effect is to stop the ETC By inhibiting cytochrome oxidase..
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Old 03-15-2013
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Originally Posted by ` Faith ` View Post
My understanding of CN is that it has more affinity to hb so it kicks O out of hb ( thus decrease O2 saturation).. But if an o2 binds to hb, CN causes it not to let go ( increase hb affinity to O2) and thus a lt shift in dissociation curve.. 3rd effect is to stop the ETC By inhibiting cytochrome oxidase..
I think that you are thinking about CO poisoning
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Old 03-15-2013
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Lol yea ur right! Was starving (even opened my notes to make sure and its CO there!)
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Old 03-15-2013
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Originally Posted by stinson View Post
In CN poisoning it stops the ETC. So that would cause the SaO2 to increase right?

I think I had a question on it but I cant seem to find it again.

Thanks! =)
Id assume yes.. Cuz tissues wont be using the O2 ( in dimple explanation)

Wiki:
Cyanide poisoning gives a high reading, because it reduces oxygen extraction from arterial blood. In this case, the reading is not false, as arterial blood oxygen is indeed high in early cyanide poisoning.
Methemoglobinemia characteristically causes pulse oximetry readings in the mid-80s.

http://en.m.wikipedia.org/wiki/Pulse_oximetry#section_3

So i guess its true.. (Didnt find answers in kaplan book)
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