Which technique provides the most reliable confirmation of endotracheal tube placement at the bedside?

• A. Capnography (end-tidal CO2 monitoring)
• B. Chest X-ray only
• C. Clinical observation alone
• D. Pulse oximetry alone

Answer: (A)

The essential idea here is how to confirm endotracheal tube placement quickly and reliably at the patient's bedside. Capnography does that by measuring the amount of carbon dioxide in exhaled air and displaying a waveform. A consistent end-tidal CO2 signal during and after placement confirms that the tube is in the trachea and that ventilation is actually delivering gas to the lungs. The waveform provides immediate, continuous feedback and remains useful even if chest compressions or poor perfusion are present, which can complicate other signs of intubation.

Chest X-ray can confirm placement, but it’s a delayed, imaging-based check and may not reflect real-time tube position during the critical moments of intubation. Clinical observation alone—watching for chest rise, listening for breath sounds, or feeling air movement—can be misleading, as these signs are not specific and can appear with misplaced tubes or other ventilation scenarios. Pulse oximetry tells you how well oxygen is getting into the blood, but it does not confirm where the tube is or whether ventilation is actually reaching the lungs, and it can remain normal for a time even with esophageal intubation.

So capnography provides the most reliable, real-time confirmation of correct endotracheal tube placement at the bedside.