Glossary of Terms

Atelectasis
A term used to describe a complete or partial collapse of a portion of the lung. The lungs are made up of millions of tiny air sacs called alveoli. Different conditions can cause these alveoli to collapse, which can result in impaired breathing and can lead to pneumonia. Atelectasis can be detected on chest x-ray and is treated by taking measures to re-expand the collapsed alveoli. These measures may range from encouraging the patient to take slow deep breaths, to mechanical ventilation.