Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: End of tracheostomy is 2 .5 cm above the level of the carina in appropriate position . Left subclavian tip is in upper SVC and right chest tube is unchanged in position . Low lung volumes with bibasilar atelectasis and pleural effusion , left greater than right . Interval increase in left retrocardiac and lower lobe opacities . No pneumothorax . Heart is mildly enlarged with normal mediastinal contour and hila . No bony abnormality .
    OUTPUT:
    
Interval increase in left lower lobe opacity may represent atelectasis or in the appropriate clinical setting left lower lobe pneumonia .