Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP upright chest radiograph provided . Lung volumes are low . There is probable mild bibasilar atelectasis . No large consolidation , effusion , or pneumothorax is seen . The heart size appears grossly unchanged , though poorly visualized . Mediastinal contour is normal . Bony structures are intact . No free air below the right hemidiaphragm .
    OUTPUT:
    
Limited , negative .