The term "ETCO" is often used in medical settings to refer to end-tidal carbon dioxide. This is the amount of carbon dioxide that is exhaled at the end of a breath. However, there are other terms that can be used as synonyms for ETCO. These include end-tidal CO2, end-tidal carbon dioxide monitoring, and capnography. Capnography is a technique that measures the level of CO2 that is being breathed out by a patient. This is important in monitoring a patient's respiratory function and can be used to identify problems such as respiratory distress or hypoventilation. So, if you hear the terms ETCO, end-tidal CO2 or capnography, rest assured that they all refer to the same vital function in medical care.