What is the primary method used to confirm placement of the endotracheal (ET) tube?

The primary method used to confirm placement of the endotracheal tube is based on the principle of auscultation, which is the process of listening to the sounds produced within the body. In the context of confirming ET tube placement, auscultation involves listening for breath sounds over the lungs and ensuring they are present and equal bilaterally. This is a crucial step because proper placement in the trachea allows for equal and clear ventilation sounds, whereas improper placement, such as in the esophagus, would typically result in diminished or absent breath sounds on the left side.

While other methods, such as the use of capnography and CO2 detectors, also serve as important adjuncts for confirming placement, they are not exclusively relied upon as the primary confirmation method. Capnography provides real-time monitoring of end-tidal CO2, serving as a valuable tool post-intubation to ensure ongoing proper placement, as it will show a consistent waveform if the tube is indeed in the trachea. Similarly, a CO2 detector can help confirm the presence of exhaled CO2, thus indicating correct placement.

Chest x-ray is a more definitive method for visualizing tube placement but is not immediately available in life-threatening situations and is not used