Suction is usually only required to remove secretions from the tube itself. How far the tube is inserted depends on the length of the tube. The recommended diameter of the suction catheter is given in Table 1.

Inserting the suction catheter deeper into the trachea can cause trauma, irritation to the mucosa or even a vagal episode if the carina is stimulated. Deep insertion of the suction catheter is required in some patients however. Always check the length that a suction catheter should be inserted for smaller adults and children.

Patients can find suction unpleasant, so bear this in mind.

Fig 1 is a video that demonstrates correct suction technique.