What is the most reliable indicator of successful tracheal intubation?

The most reliable indicator of successful tracheal intubation is the end-tidal CO2 waveform. This is primarily because it directly measures the carbon dioxide being expelled from the lungs, which only occurs if the endotracheal tube is positioned correctly within the trachea and not in the esophagus. The presence of a consistent end-tidal CO2 waveform confirms that air is being ventilated through the lungs, indicating that the tube is in the correct anatomical position.

While other signs may suggest successful intubation, they are not as definitive. For instance, observing chest rise can indicate ventilation but can also occur if the tube is misplaced in the esophagus, thus leading to false reassurance. Oxygen saturation levels can improve post-intubation, but they may lag behind other confirmations or be misleading if there are underlying respiratory issues. Similarly, the presence of breath sounds does not guarantee correct placement since they can be heard even if the tube is incorrectly positioned. Therefore, the end-tidal CO2 waveform stands out as the most reliable and objective measure for confirming proper tracheal intubation.