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Old 04-12-2013
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Question Methemoglobin and cyanide poisoning

Can some please explain this concept to me?

According to First Aid, "The oxidized form of hemoglobin (Fe3) doesn't bind O2 as readily but has an increase affinity for CN- (cyanide).

I thought that the oxidized form of hemoglobin (Fe3) has a higher affinity for O2 (oxygen) therefore creating a 'left shift'

And cyanide poisoning on the other hand is when Hemoglobin binds cyanide also creating a left shift.

How are these 2 related???

Someone please explain....
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Old 04-12-2013
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oxidized hemoglobin doesn't bind O2 (so theoretically oxidizing agents right shift the curve)

CN acts on mitochondrial complex 4 (i havent heared of its action causing left shift other than from goljan)

CO on the other hand left shifts the curve
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