Physiology of Capnography Details Created: Tuesday, 29 July 2008 13:53 Last Updated: Tuesday, 31 December 2013 16:29 Written by Bhavani Shankar Kodali MD Hits: 50655 Basic Physiology of a Capnogram Trend Capnogram Components of a Time Capnogram Volume Capnogram 'verses' Time capnogram Capnogram and Tidal volume PETCO2 and Cardiac output Phase IV (a-ET)CO2 difference and Alveolar dead space Negative (a-ET)PCO2 differences