Continuous capnography monitoring is now standard for all ventilated patients on intensive care units (ICUs) in the UK. We would like to describe a novel method of teaching our junior doctors and ICU nurses about interpretation of capnograph traces (Fig. 1). - ‘Hats and caps’ guide to capnography traces on intensive care: posh hats are good. #Diagnosis #PCC #Capnography #Waveform #ETCO2 #EndTidalCO2 #Hats #Caps #Interpretation #pulmonary