The initial information given to the candidates was -
In this station you will be asked to draw and discuss a capnograph tracing.
Draw a graph of partial pressure of CO2 versus time, from a ventilated patient, i.e. a
‘capnograph tracing’.
This viva explored the candidates’ knowledge in relation to the following points

  • Capnograph trace and information that can be ascertained from it
  • Methods used to measure partial pressure of CO2 and the underlying principles
  • ETCO2 and PaCO2 relationships and factors that influence it
  • Capnograph and deadspace

Examination feedback: General there was a lack of depth in the understanding of the
capnograph. Specifically what it measures, principles of measurements and an understanding
of deadspace.