What is the purpose of the cuff in an endotracheal tube?

The purpose of the cuff in an endotracheal tube is primarily to aid in positive pressure ventilation. When the cuff is inflated, it creates a seal against the walls of the trachea, which allows for effective delivery of positive pressure ventilation by preventing air from escaping around the tube. This is crucial when providing respiratory support to ensure that the air being delivered reaches the lungs rather than leaking out, thereby enhancing the effectiveness of mechanical ventilation.

While the cuff can also contribute to preventing aspiration by forming a barrier that can reduce the chance of secretions entering the airway, its primary and most critical role is to allow for positive pressure ventilation. This functional characteristic makes the cuff an essential component for ensuring that the patient can receive adequate ventilation, especially during intubation and mechanical ventilation scenarios.