About cyclopropane as an anesthetic: it use to be used, but it has now been replaced by others.
British Dictionary definitions for cyclopropane
a colourless flammable gaseous hydrocarbon, used in medicine as an anaesthetic; trimethylene. It is a cycloalkane with molecules containing rings of three carbon atoms. Formula: C3H6; boiling pt: –34°C
(sī'klə-prō'pān', sĭk'lə-) A highly flammable, explosive, colorless gas that was once in wide use as an anesthetic but has been mostly replaced by less flammable gases. The three carbon atoms of cyclopropane form a triangular ring. Chemical formula:C3H6.