Carbon monoxide poisoning at high altitudes.

Carbon monoxide (CO) poisoning is a common problem encountered in a wide variety of settings, including both suicide attempts and accidental exposures. Fatal CO exposure occurred in two young, healthy mountain climbers who succumbed to fumes generated by a small cook stove in the enclosed space of their tent at 14,200 feet on Mount McKinley. There is the potential for confusing mild to moderate CO poisoning with the signs and symptoms of altitude illness. Physicians who deal with wilderness and environmental emergencies should be aware of this serious hazard.