Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP portable upright view of the chest . Lung volumes are low with mild bibasal atelectasis noted . No convincing evidence for pneumonia . No free air below the right hemidiaphragm . Cardiomediastinal silhouette is normal . Bony structures are intact .
    OUTPUT:
    
No signs of free air below the right hemidiaphragm .