End Tidal Carbon Dioxide Characterization And Performance Analysis Of A Capnography System
Capnography is a non-invasive technique used for measuring and monitoring the level of carbon dioxide (CO2)
during respiration. The detection of accurate end tidal carbon dioxide (ETCO2) value results in clinical diagnosis of the
patient’s breathing mechanism. Therefore, it is one of the compulsory equipment used in most medical procedures for both
adults and neonates. Based on the principle of spectrophotometer, Non Dispersive Infrared Radiation (NDIR) technique is
used to detect the ETCO2 value. This paper describes an algorithm and system for the instant detection of the peaks in a
capnograph and illustrates the measurement of respiration-based parameters for the development of a stable and reliable
capnography unit. The system was subjected to different parametric configurations to achieve accurate results. Four major
patient specific parameters are identified and the theoretical concentration is displayed in comparison with the practically
obtained value. Performance analysis of the system led to an accuracy of 96.90% in comparison with American society for
testing and materials (ASTM) standard and a reference benchmark.
Index Terms— Capnography, ETCO2, NDIR, Peak Detection, Spectrophotometer.