<prompt> Capnography is useful forDetermining Vaporizer malfunction or contaminationDetermining circuit hypoxiaDetermining the appropriate placement of endotrachealDetecting concentration of oxygen in the anesthetic circuit.  <response>: capnography is the ideal method of determining the correct placemet of endotracheal tube. Identification : loss of waveform of capnogram.decline in End tidal CO2 levels. 