Capnography provides the measurement and graphic display of CO2 at the airway.

Capnography provides the measurement and graphic display of CO2 at the airway.

• A. It provides only the numerical ETCO2
• B. It provides only the waveform
• C. Capnography provides both numerical ETCO2 and a capnogram waveform
• D. It provides none of these

Answer: (C)

Capnography combines two things: a numeric value for end-tidal CO2 and a continuous graphic trace of CO2 over time, the capnogram. The end-tidal CO2 value reflects the CO2 concentration at the end of expiration, giving a single quantitative measure to trend ventilation and perfusion. The capnogram waveform shows how CO2 rises during expiration, the shape and slope of the plateaus, and changes across breaths, revealing ventilation patterns, airway patency, rebreathing, or obstruction. Because it provides both the numerical ETCO2 and the dynamic waveform, it covers both the exact value and the real-time ventilation pattern, making it the most informative option.

Capnography combines two things: a numeric value for end-tidal CO2 and a continuous graphic trace of CO2 over time, the capnogram. The end-tidal CO2 value reflects the CO2 concentration at the end of expiration, giving a single quantitative measure to trend ventilation and perfusion. The capnogram waveform shows how CO2 rises during expiration, the shape and slope of the plateaus, and changes across breaths, revealing ventilation patterns, airway patency, rebreathing, or obstruction. Because it provides both the numerical ETCO2 and the dynamic waveform, it covers both the exact value and the real-time ventilation pattern, making it the most informative option.