Waveform capnography is used to confirm airway device placement and monitor ventilation.

• A. Pulse Oximetry
• B. Waveform Capnography
• C. Sputum Culture
• D. Chest Radiograph

Answer: (B)

Waveform capnography provides real-time confirmation of airway device placement and ongoing ventilation by measuring and displaying exhaled CO2 as an identifiable waveform with an end-tidal CO2 value. If the airway device is correctly placed in the trachea, CO2 is expelled with each breath and a CO2 waveform appears promptly, confirming placement. Beyond placement, capnography tracks ventilation by showing the shape and level of the end-tidal CO2, so you can detect hypoventilation, hyperventilation, airway obstruction, disconnections, or tube dislodgement as they happen. Other options don’t offer this combination: pulse oximetry only reflects oxygen saturation and can lag behind changes in ventilation, not confirming tube position; a sputum culture is unrelated to airway placement or ventilation status; chest radiography can show where the tube is but is static and provides information only after a delay.