Pulmonary Collapse. — From compression or from obstructions in the lungs, air may be prohibited from entering the air cells, and the result will be collapse of the vesicles. It very frequently occurs in children during the course of whooping cough, bronchitis, measles and croup[1]. It is exceedingly fatal in very young persons and in the aged. It is fully treated of as capillary bronchitis in the article on Bronchitis.[1] Wikipedia suggests that it most commonly occurs as post-surgical atelectasis.
Excerpts from J. H. Greer's "A Physician in the House: for family and individual consultation", published in 1897. Annotations provided throughout. This is not medical advice - if you're sick, see a doctor.