What does carbon monoxide do to your red blood cells ?

just to clarify, CO has a higher binding affinity than O2 for hemoglobin, the structure in red blood cells that normally carries oxygen. it is not irreversible, just preferable. you treat patients of CO poisoning with 100% O2, hoping to get some O2 back on the hemoglobin through its ubiquity. without O2 delivered to muscles and the brain, you die. curiously, CO is odorless. evolutionarily, we must not have had much of a danger from it.