Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are clear without focal consolidation . No pleural effusion or pneumothorax is seen . The cardiac and mediastinal silhouettes are unremarkable . There is a large amount of free air beneath the hemidiaphragms .
    OUTPUT:
    
Clear lungs . Large amount of pneumoperitoneum . The patient is reportedly status post recent cholecystectomy ; amount of air appears larger than would be expected for cholecystectomy 5 days prior , unclear whether findings may relate to post surgical change , bowel perforation not excluded .