Capnography and pulse oximetry

摘要

The possible use of non-invasive monitoring (of great clinical significance) has given capnography a peculiar role in the assessment of the ventilatory function during anaesthesia. Such monitoring allows for constant display of CO_2 concentration expressed as a function either of time (conventional capnography) or end-tidal volume (volumetric capnography). Conventional capnograms can be divided into inspiratory and expiratory segments, the latter typically consisting of four phases. The present paper reports on some situations which, unlike clinical routine, require careful interpretation of capnographic data, which should always be adequately contextualized.