In suspected carbon monoxide poisoning during flight, what oxygen therapy is indicated?

• A. 50% oxygen via nasal cannula and monitor.
• B. 100% oxygen via tight-fitting mask; arrange for rapid evacuation and consider hyperbaric therapy if CO exposure is confirmed.
• C. High-flow oxygen only at sea level.
• D. Ventilate with room air and seek medical clearance.

Answer: (B)

The key idea is to rapidly maximize oxygen delivery to displace carbon monoxide from hemoglobin. In suspected CO poisoning during flight, give 100% oxygen as soon as possible using a tight-fitting non-rebreather mask. This delivers the highest FiO2 and speeds up the dissociation of CO from hemoglobin, reducing the CO-binding time and helping tissues receive adequate oxygen again.

Delivering 100% oxygen via a nasal cannula won’t achieve the same FiO2 and is not sufficient for CO poisoning. Ventilating with room air would not displace CO effectively, and relying on “high-flow oxygen” without ensuring a truly high FiO2 isn’t optimal in this scenario. Once stabilized on 100% oxygen, arrange rapid evacuation to definitive care, and consider hyperbaric therapy if CO exposure is confirmed and neurologic symptoms or other indications are present, since hyperbaric treatment further accelerates CO clearance and can improve outcomes.