What is the purpose of capnography in airway management?

• A. To measure blood pressure.
• B. To assess airway edema.
• C. To evaluate heart rate.
• D. To confirm proper placement of ETT or SGA and monitor ventilation effectiveness.

Answer: (D)

Capnography provides a real-time readout of exhaled carbon dioxide and a waveform that reflects how well ventilation is working. This makes it the primary tool for confirming that an airway device is in the trachea rather than the esophagus and for continuously monitoring ventilation after placement. A correctly placed endotracheal tube or supraglottic airway will produce a consistent CO2 waveform and a measurable end-tidal CO2 value. If the device is not in the airway, the CO2 may be absent or markedly reduced, producing a flat or abnormal waveform and signaling the need to reposition. Additionally, tracking the waveform and EtCO2 over time helps you judge ventilation effectiveness and adjust support as needed. The other options relate to different physiologic measurements that are obtained with separate equipment, not capnography.