What does the presence of end-tidal CO2 indicate after intubation?

The presence of end-tidal CO2 after intubation indicates that the endotracheal tube is correctly positioned in the trachea. When the tube is in the trachea, it allows for the effective exchange of gases, which results in the exhalation of carbon dioxide. The detection of end-tidal CO2 demonstrates that the lungs are adequately ventilated and that CO2 is being expelled from the body.

In contrast, if the tube were incorrectly placed in the esophagus, there would be no or very minimal end-tidal CO2 detected, since the esophagus does not facilitate gas exchange. This is a critical aspect in confirming correct intubation, as the detection of CO2 is one of the most reliable indicators that the airway is properly secured in the trachea. Additionally, the presence of end-tidal CO2 does not directly indicate the need for suctioning, nor does it provide information about respiratory failure. Therefore, the correct interpretation of end-tidal CO2 after intubation hinges on the confirmation that the tube is in the trachea.