Cyanosis is not seen in: (A) CHF, (B) COPD, (C) CO poisoning, (D) High altitude
Answer is C. Cyanosis is a bluish discoloration of the skin and mucous membranes resulting from inadequate oxygenation of the blood and not seen in CO poisoningRef: Hutchison&;s Clinical Methods, 23ed edition, page no: 21