A 42-year-old woman is admitted to the emergency department after being rescued from a house fire. She is presenting with confusion, headache, and a bright red skin coloration. Suspecting cyanide poisoning from smoke inhalation, what is the most appropriate initial treatment?
Provide supplemental oxygen only.
Begin aggressive intravenous fluid administration.
Administer hydroxocobalamin intravenously.
Perform gastric lavage.