206k views
5 votes
Patients suffering from carbon monoxide poisoning are treated with pure oxygen to remove carbon

monoxide from the hemoglobin (Hb) in their blood. The two relevant equilibria are:

Hb + 4 CO(g)<-> Hb(CO)₄

Hb + 4 O₂(g) <->Hb(O₂)₄

However, the value of the equilibrium constant for CO binding to Hb is greater than that for O₂

So, how then do you explain that treatment with pure oxygen may help remove carbon monoxide from the hemoglobin of those poisoned patients?

User Yummypasta
by
7.6k points

1 Answer

4 votes

Final answer:

In treating carbon monoxide poisoning, pure oxygen administration leverages Le Chatelier's principle by increasing oxygen concentration to outcompete CO for binding with hemoglobin, thus favoring oxyhemoglobin formation and leading to CO displacement and exhalation.

Step-by-step explanation:

Patients suffering from carbon monoxide poisoning are treated with pure oxygen to remove carbon monoxide (CO) from the hemoglobin (Hb) in their blood. Even though CO has a 200 times greater affinity for hemoglobin than oxygen, increasing the concentration of oxygen can displace CO from Hb because of Le Chatelier's principle. This principle suggests that the equilibrium will shift to counteract the change. In this case, by supplying a high concentration of oxygen, it shifts the equilibrium away from the formation of carboxyhemoglobin and favors the formation of oxyhemoglobin instead.

When pure oxygen is administered, the partial pressure of O2 in the lungs rises dramatically, thereby increasing the concentration of O2 in the blood. This allows for a greater chance of oxygen outcompeting CO for the binding sites on Hb.

As a result, oxyhemoglobin forms more readily, and CO is released from Hb and exhaled from the lungs. Continuous oxygen treatment at higher pressures further helps to displace CO from Hb and return oxygen levels to normal, which is vital in treating CO poisoning effectively.

User Diatrevolo
by
7.9k points