Hemoglobin modifications Flashcards
1
Q
How does modification affect O2
A
Tissue hypoxia from
low O2 sat and low O2 content
2
Q
Methemoglobin
A
Oxidized form of hemoglobin (ferric, not ferrous Fe2+) does not bind O2 as readiy, but high affinity for cyanide
3
Q
How to treat cyanide poisoning
A
Nitrate to oxidize hemoglobin to methemoglobin,
which binds cyanide, allowing cytochrome oxidase to function.
Use thiosulfate to bind this cyanide, forming thiocyanate, which is renally excreted.
4
Q
How to treat methemoglobin
A
Methylene blue
5
Q
Carboxyhemoglobin
A
CO instead of O2,
Causes low oxygen-binding capacity with a left shift in the oxygen-hemoglobin dissociation curve
Low oxygen unloading in tissue.
6
Q
CO vs O2
A
200x greater affinity than O2 for hemoglobin
