Abstract
It is a commonly held assumption that retained airway mucus places the postoperative patient at greater risk of developing clinically significant atelectasis or pneumonia. This assumption is supported by this review of the available literature. However, not all postoperative patients are equally at risk of developing retained mucus. Factors such as the presence of pre-existing diseases, perioperative impairments to normal mucociliary clearance, and relative impairment of cough effectiveness increase the likelihood of retained mucus. As retained mucus can contribute to postoperative atelectasis and pneumonia, this would suggest a role for the promotion of airway clearance techniques in the selected patient. Questions exist, however, as to the efficacy of physiotherapy airway clearance techniques in the postoperative patient.