Which of the following is NOT a use of capnography?

• A. Determine blood glucose
• B. Confirm end-tidal CO2
• C. Verify tube placement
• D. Monitor ventilation status

Answer: (A)

Capnography gives real-time information about CO2 in the airway, shown as both a numerical end-tidal CO2 value and a continuous capnogram waveform. This is why it’s used to confirm that CO2 is being exhaled at the end of expiration and to verify airway placement after intubation—the presence of a reliable ETCO2 waveform indicates the tube is in the trachea rather than the esophagus. It also helps monitor ventilation status by showing how effectively CO2 is being eliminated, allowing you to detect hypoventilation, hyperventilation, apnea, or return of spontaneous circulation during resuscitation.

Determining blood glucose, on the other hand, is not a capability of capnography. Glucose assessment requires a glucose-specific measurement method (fingerstick meters or laboratory assays), not CO2 monitoring.