Final answer:
If no bilateral breath sounds are heard when ventilating through the #1 port of the ETC, you should switch to the #2 port for ventilation.
Step-by-step explanation:
After placing the Esophageal Tracheal Combitube (ETC), if no bilateral breath sounds are heard when ventilating through the #1 port, you should switch to the #2 port for ventilation.
The Esophageal Tracheal Combitube is a device used in emergency situations for airway management. It has two ports, #1 and #2, that are used for ventilation. If no bilateral breath sounds are heard when ventilating through the #1 port, it indicates that the ETC may not be properly placed and the #2 port should be used for ventilation.