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Old 04-06-2012
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Poison Why Cherry Red Appearance in Carbon Monoxide Poisoning?

Could someone explain why in CO Poisoning there is a decreased SaO2 (or O2 carrying capacity of Hemoglobin) but the patient presents with cherry red skin? What causes the cherry red colored skin appearance?
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Old 04-06-2012
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Because that's the color of CO. I think that's what Goljan said on the 1st lecture. Turco said that they're cherry red, but didn't really say why.
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Originally Posted by tootsie View Post
Because that's the color of CO. I think that's what Goljan said on the 1st lecture. Turco said that they're cherry red, but didn't really say why.
oh, see that's why its confusing because in pathoma, dr. sattar said that its because the hemoglobin is so tightly packed that its reflective ... or something along those lines
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Old 04-06-2012
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Wait, isnt cherry red skin is the presentation of a nitrated water drinking lover with methemoglobin poisoning?
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Originally Posted by DocSikorski View Post
Wait, isnt cherry red skin is the presentation of a nitrated water drinking lover with methemoglobin poisoning?
with methemoglobinemia you would get cyanosis right ? and cyanotic individuals don't have cherry red skin ?
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Originally Posted by tootsie View Post
Because that's the color of CO. I think that's what Goljan said on the 1st lecture. Turco said that they're cherry red, but didn't really say why.
Red isn't the color of CO, it's the color of saturated hemoglobin. CO is colorless.

I'm not sure if this is right, but this is how I imagine that it works (and helps me remember it)...

Usually, hemoglobin gets desaturated in the tissue and transferred back to venous blood. So you have bright red (highly saturated) blood in the arteries, bluish (desaturated) blood in the veins, and something in between in the capillaries.

In CO poisoning, because hemoglobin has such a high affinity for CO, it doesn't get desaturated in the tissue. So that means that the blood in the capillaries and veins is just as saturated as the arterial blood. As a result, your skin will exhibit a much redder color.
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Originally Posted by shan564 View Post
Red isn't the color of CO, it's the color of saturated hemoglobin. CO is colorless.

I'm not sure if this is right, but this is how I imagine that it works (and helps me remember it)...

Usually, hemoglobin gets desaturated in the tissue and transferred back to venous blood. So you have bright red (highly saturated) blood in the arteries, bluish (desaturated) blood in the veins, and something in between in the capillaries.

In CO poisoning, because hemoglobin has such a high affinity for CO, it doesn't get desaturated in the tissue. So that means that the blood in the capillaries and veins is just as saturated as the arterial blood. As a result, your skin will exhibit a much redder color.

Thanks, that makes sense. I guess that's what Dr. Sattar meant in Pathoma that since the Hemoglobin is so tightly packed, it is not desaturated, if anything, its more saturated (not by O2) and therefore there is a cherry red colored skin appearance.
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Quote:
Originally Posted by Hope2Pass View Post
Thanks, that makes sense. I guess that's what Dr. Sattar meant in Pathoma that since the Hemoglobin is so tightly packed, it is not desaturated, if anything, its more saturated (not by O2) and therefore there is a cherry red colored skin appearance.
Yeah, that was my understanding of what he said. Total coincidence... I just watched that lecture yesterday.
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Methemoglobin is chocolate colored.

That's right CO makes its victims pink...
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Quote:
Originally Posted by shan564 View Post
Red isn't the color of CO, it's the color of saturated hemoglobin. CO is colorless.

I'm not sure if this is right, but this is how I imagine that it works (and helps me remember it)...

Usually, hemoglobin gets desaturated in the tissue and transferred back to venous blood. So you have bright red (highly saturated) blood in the arteries, bluish (desaturated) blood in the veins, and something in between in the capillaries.

In CO poisoning, because hemoglobin has such a high affinity for CO, it doesn't get desaturated in the tissue. So that means that the blood in the capillaries and veins is just as saturated as the arterial blood. As a result, your skin will exhibit a much redder color.

Brilliant!! also will help me remember it as well, thanks
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Old 04-07-2012
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becuase of o2 unloading (:
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Old 04-22-2012
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Default cherry red pigment

Actually, the answer to your question is different.
The cherry red color of skin is due to Co binding to myoglobin
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Old 03-02-2014
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CO is COLORLESS, ODORLESS AND TASTELESS
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Clinical-Signs, Hematology-, Physiology-, Toxicology-

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