Advanced Cardiovascular Life Support (ACLS) Practice Exam

What is the most reliable method of confirming and monitoring correct placement of an endotracheal tube?

1. Bag-valve-mask ventilation

2. Continuous waveform capnography

3. Chest X-ray

4. Manual auscultation

The correct answer is: Continuous waveform capnography

The most reliable method of confirming and monitoring correct placement of an endotracheal tube is continuous waveform capnography. This technique provides real-time assessment of exhaled carbon dioxide levels, which signifies effective ventilation. When the endotracheal tube is correctly positioned in the trachea, the presence of carbon dioxide in exhaled air is detectable, resulting in a consistent waveform on the capnography monitor. This method not only confirms that the tube is in the correct location but also allows for continuous monitoring throughout the procedure, ensuring that any dislodgment or incorrect placement can be identified promptly. In contrast, while bag-valve-mask ventilation may provide breath sounds, it does not definitively confirm proper tube placement, as inadequate ventilatory support may still occur even if sounds are heard. Chest X-ray, though useful for confirming placement, is not a real-time method and can lead to delays in patient care. Manual auscultation can assist in assessing tube placement but is subjective and may not detect subtle misplacement or changes over time, making it less reliable compared to continuous waveform capnography.