Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left subclavian central venous catheter terminates in the lower superior vena cava . A nasogastric tube terminates in the stomach . The lung volumes are low . The cardiac , mediastinal and hilar contours appear stable . Minimal opacities at each lung base suggest minor atelectasis . Otherwise , the lungs appear clear . High density material in the visualized transverse and splenic flexure portions of the colon suggests a recent prior contrast administration for a radiologic study . Small quantity of hyperdense material at the base of the right lung may represent trace prior aspiration of barium .
    OUTPUT:
    
No evidence of acute cardiopulmonary disease .