Anaes Vivas · Airway management & difficult airway
Data viva — the capnography waveform
A data viva on the capnography trace — the four phases of the normal waveform, what it confirms (the single most reliable proof of tracheal intubation), and the abnormal traces an examiner expects you to interpret. Anchored to the NAP4 mandate for continuous capnography wherever an airway device is in place.
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ANZCAFRCAABAEDAIC
Prompt
A continuous waveform capnography trace showing a normal square-wave trace at a steady end-tidal carbon dioxide of around 5 kPa, alongside the oxygen saturation.
Stimulus
A continuous waveform capnography trace, obtained from the breathing circuit via a sidestream or mainstream analyser, displaying carbon dioxide concentration against time. The trace is a regular, square wave with an end-tidal value of around 5 kPa.[8]
References2ShowHide
- [7]Cook TM, Woodall N, Frerk C; Fourth National Audit Project. Major complications of airway management in the UK: results of the Fourth National Audit Project (NAP4). British Journal of Anaesthesia, 2011.PMID 21447488
- [8]Bersten AD, Soni N (eds) Oh's Intensive Care Manual. 8th edition, Elsevier, 2018.