FINDINGS:
Lung volumes are low.  This accentuates the size of the cardiac silhouette
 which is top normal.  The mediastinal and hilar contours are unremarkable. 
 There is crowding of the bronchovascular structures, but no overt pulmonary
 edema is demonstrated.  There is a possible small left pleural effusion. 
 Patchy opacity in the retrocardiac region is likely atelectasis given the low
 lung volumes, but an early pneumonia is not completely excluded.  There is no
 pneumothorax.  No acute osseous abnormalities seen.

IMPRESSION:
Low lung volumes.  Minimal patchy retrocardiac opacity may reflect atelectasis
 though infection cannot be completely excluded.  Probable trace left pleural
 effusion.