Certified Respiratory Therapist Practice Exam

What indicates an obstruction in the endotracheal (ET) tube of a patient being mechanically ventilated?

1. Clear lung sounds

2. High pressure required to deliver the volume

3. Normal airway resistance

4. Easy passage of suction catheter

The correct answer is: High pressure required to deliver the volume

An obstruction in the endotracheal (ET) tube of a patient on mechanical ventilation is indicated by the high pressure required to deliver the volume of air. When there is an obstruction, it restricts airflow, necessitating more pressure from the ventilator to achieve the same tidal volume. This high pressure is an important clinical indicator that there may be a problem within the airway, such as the ET tube being kinked, blocked by secretions, or partially occluded. In contrast, clear lung sounds and a normal airway resistance would suggest that there is no significant obstruction affecting airflow or ventilation. Additionally, the easy passage of a suction catheter would indicate that the airway is open and not obstructed. Therefore, the presence of high peak inspiratory pressures is a key sign that warrants further investigation into the status of the ET tube and airway.