Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP upright chest radiograph was provided . Midline sternotomy closure devices are present . There is no definite sign of free air below the right hemidiaphragm . There is a blunted right CP angle , suggesting a small right effusion . The lungs are otherwise clear . Cardiomediastinal silhouette is stable with top normal heart size . No pneumothorax . Bony structures are intact .
    OUTPUT:
    
Small right pleural effusion . No signs of free air below the right hemidiaphragm .