Overview
Inner tubes (or cannulae) provide an inner sleeve or lining to the main tracheostomy tube. They can be removed from within the outer tube, inspected, cleaned and replaced (or a new one inserted). This can help to keep the airway clear of secretions. There are a variety of different inner tubes to match the outer tracheostomy tube, including single-use/disposable, fenestrated and different locking mechanisms that vary between tube manufacturers.
The frequency of tube change will vary depending on the secretion load of the patient at that time. As a guide, an inner tube should be removed and inspected at least once per 8-hour shift. Heavily soiled inner tubes (like the example in the image) should prompt more frequent changes. An inner tube should be removed immediately if the patient shows any signs of respiratory distress.
This is a clean, not a sterile procedure.
A wide variety of solutions are used across health care including tap water, sterile water, sterile saline and hydrogen peroxide 10 w/v (3%).
Evidence to support the use of tap, sterile water or other solutions is equivocal and local policies vary in their recommendations, influenced by the available water supply and quality, types of tubes used and patient condition. Hospitalized patients with medical problems are a different population to community patients and generally a higher standard of cleanliness is appropriate.
It is important to note that the central rationale for cleaning of inner cannula is to mechanically remove debris which may physically obstruct a patient’s airway. A secondary outcome of mechanical cleaning is a reduction in the numbers of microbes present.