What is the initial and definitive treatment for carbon monoxide poisoning?

• A. 100% inspired oxygen initially; hyperbaric oxygen therapy in selected cases with severe poisoning or neurologic symptoms
• B. Nebulized bronchodilators
• C. Antibiotics
• D. Observation only

Answer: (A)

Carbon monoxide poisoning should be treated by rapidly increasing the amount of oxygen in the blood to displace CO from hemoglobin and other binding sites. The first and most important step is delivering 100% inspired oxygen as soon as CO exposure is suspected. This dramatically accelerates the clearance of carboxyhemoglobin, reducing ongoing tissue hypoxia and the risk of further injury.

In more severe cases, or when there are neurologic symptoms such as confusion, loss of consciousness, seizures, or signs of brain injury, hyperbaric oxygen therapy is used as a definitive aid. Breathing 100% oxygen at high pressure further accelerates CO removal and can help reduce the risk of delayed neurologic sequelae, especially in patients with significant neurologic impairment, very high carboxyhemoglobin levels, or specific risks like pregnancy.

Nebulized bronchodilators and antibiotics do not address the underlying problem of CO binding and are not standard treatments for CO poisoning. Observation alone is insufficient because CO rapidly impairs oxygen delivery and can cause evolving hypoxia and organ injury if not promptly treated.

So, the best approach is to start with 100% oxygen right away, with hyperbaric oxygen therapy considered in selected severe or neurologically affected cases.