In the treatment of carbon monoxide poisoning, what is the standard initial therapy?

• A. High flow oxygen
• B. Hyperbaric chamber in extreme cases
• C. Monitor cardiac status
• D. Begin chelation therapy

Answer: (A)

High-flow oxygen is the standard initial therapy. Carbon monoxide binds to hemoglobin with very high affinity, forming carboxyhemoglobin and preventing adequate oxygen delivery to tissues. Providing 100% oxygen rapidly increases the amount of dissolved oxygen in the blood and speeds the dissociation of CO from hemoglobin, reducing tissue hypoxia and shortening the carboxyhemoglobin half-life. Hyperbaric oxygen therapy can be considered in severe cases (such as significant neurologic symptoms or pregnancy), but it is not the routine first step due to resource intensity and timing. Monitoring cardiac status is important for overall care, but it does not replace the need for immediate oxygen therapy; chelation therapy is not used for CO poisoning.