Airflow Through the Tubes
Airflow through the different tubes
Fig 1 shows a cuffed tracheostomy tube in situ. Airflow should only be through the tube to the lungs, allowing positive pressure ventilation if the tube is correctly sited.
In a deflated cuffed tube or an un-cuffed tube, airflow will be through the upper airway and tracheostomy tube as in the centre figure (Fig 2).
With a fenestration tube, airflow will be increased through the upper airway and tracheostomy tube as in the right-hand figure (Fig 3).