What is the initial management for carbon monoxide poisoning?

• A. Observation only.
• B. Nebulized bronchodilators.
• C. 100% oxygen via non-rebreather; consider hyperbaric O2 in severe cases.
• D. IV acyclovir.

Answer: (C)

Carbon monoxide poisoning is treated by rapidly delivering high concentrations of oxygen to displace CO from hemoglobin and to speed up its elimination, restoring oxygen delivery to tissues. The initial step is to give 100% oxygen as soon as possible, typically via a non-rebreather mask. This high-flow oxygen greatly accelerates CO clearance compared with room air and helps reverse tissue hypoxia. In more severe cases—such as patients with confusion, loss of consciousness, seizures, neurologic deficits, signs of myocardial ischemia, or in pregnant patients—hyperbaric oxygen therapy may be considered because it can further hasten CO removal and improve neurologic outcomes. The half-life of carboxyhemoglobin drops from several hours on room air to roughly 40–90 minutes with 100% oxygen, and even shorter with hyperbaric therapy. While other interventions like observation alone or bronchodilators, or antiviral therapy, don’t address the underlying issue, the priority is rapid oxygenation and supportive care, with hyperbaric therapy reserved for the most severe or high-risk cases.