Capnography is required for every patient in cardiac arrest. Which of the following best describes capnography?

• A. A monitoring measure of exhaled carbon dioxide
• B. A device to measure core temperature
• C. A device that records heart rate
• D. A method to deliver high oxygen

Answer: (D)

Capnography is the continuous monitoring and display of the amount of carbon dioxide in a patient’s exhaled breath. It provides a capnogram waveform and a numeric end-tidal CO2 (ETCO2) value, which are used during CPR to assess ventilation, detect effective chest compressions, verify airway placement, and gauge perfusion. In cardiac arrest, rising ETCO2 or a visible waveform can indicate return of spontaneous circulation, making capnography a vital real-time feedback tool. It is not a measure of core temperature, does not record heart rate, and does not deliver oxygen—those functions are handled by other devices.