What is considered the most reliable indicator of successful tracheal intubation?

The most reliable indicator of successful tracheal intubation is the sustained end-tidal carbon dioxide (ETCO2) waveform. When an endotracheal tube is correctly placed in the trachea, the patient’s exhaled breath will carry carbon dioxide from the lungs, resulting in a measurable level of ETCO2. The continuous waveform that appears on the capnography monitor provides immediate feedback about the position of the tube, confirming that it is in the airway and not in the esophagus.

This is vital because while visual confirmation of tube placement can indicate success, it does not guarantee that the tube is positioned correctly in the trachea rather than the esophagus, especially in emergency situations where visualization may be challenging. Similarly, while auscultating breath sounds can give clues about proper placement, it can be subject to interpretation and may not provide a definitive confirmation. Sustained oxygen saturation can reflect effective ventilation but does not necessarily confirm correct tube placement by itself, since oxygen saturation might remain satisfactory temporarily even if the tube is not positioned properly.

Thus, the sustained ETCO2 waveform is recognized as the best objective measure indicating that successful intubation has occurred, as it directly correlates with correct tube placement in the airway