Carbon Monoxide Poisoning

A 39-year-old female executive has a several-month history of fatigue, headache, and memory lapse. Multiple specialists have performed evaluations, but no diagnosis has been established. During a period of feeling worse than usual, she called a friend, who arrived at the residence to find the woman semicomatose and called 911. The patient was given supplemental oxygen and transported to the emergency department, where she is alert and has nonfocal findings on examination. Her carboxyhemoglobin level is 18%. How should she be treated? What is the expected outcome?