Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable semi-erect chest radiograph demonstrate persistent low lung volumes . There is moderate pulmonary edema with left lower lung opacification , new since prior chest radiograph dated 1 day prior . This may represent atelectasis versus superimposed pneumonia . The endotracheal tube is not well seen and may be obscured by the chin . There is subcutaneous emphysema in the right supraclavicular region with no evidence of mediastinal air . A right IJ is seen at the cavoatrial junction . A left chest tube projects to the level of the aortic arch . Extensive abdominal free air is noted . Known and unchanged cardiomegaly . No pneumothorax .
    OUTPUT:
    
Moderate pulmonary edema with left lower lobe opacification which is in the appropriate clinical setting may represent superimposed pneumonia or atelectasis .