Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable semi-erect chest radiograph ___ at 04 :34 is submitted .
    OUTPUT:
    
Right internal jugular central catheters are unchanged in position . Endotracheal tube continues to have its tip approximately 4 cm above the carina . Nasogastric tube coursing below the diaphragm with the tip not identified . Overall cardiac and mediastinal contours are within normal limits status post median sternotomy . There are persistent bibasilar patchy opacities which could reflect areas of pneumonia or atelectasis . Overall , the edema appears to have improved . No pneumothorax .