Which statement best describes the role of ETCO2 monitoring in airway management?

• A. Only measures oxygen level
• B. Measures heart rate
• C. Predicts blood pressure
• D. Confirm tube placement and monitor ventilation

Answer: (D)

End-tidal CO2 monitoring gives a real-time readout of ventilation and a confirming waveform that directly ties to how well air and CO2 are moving in and out of the lungs. The measurement reflects CO2 at the end of exhalation, so when the endotracheal tube is correctly placed in the trachea, CO2 is expelled and you see a consistent capnography trace with a normal range. If the tube is in the esophagus or there’s a disconnection, the trace may be flat or substantially reduced, signaling you to reposition or check connections. Beyond placement, ETCO2 tracks how ventilation is proceeding over time—drops in a flat trace or sudden changes indicate apnea, hypoventilation, disconnection, or shifts in perfusion, while changes in the waveform correlate with ventilation adjustments. Oxygen level monitoring is a separate measure (SpO2), and heart rate or blood pressure are tracked by other monitors. So, ETCO2 monitoring is best described as a tool to confirm tube placement and continuously monitor ventilation.