Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The distal part of a left - sided PICC has flipped upward coursing retrograde . The cardiac , mediastinal and hilar contours appear unchanged . Perihilar fullness and hazy prominent pulmonary vascularity have mildly decreased . Small to moderate pleural effusions persist with patchy basilar opacities , not specific , although probably due to atelectasis with low lung volumes .
    OUTPUT:
    
1 . Improvement in pulmonary edema . 2 . Suspected pleural effusions and patchy parenchymal densities likely due to atelectasis . 3 . Tip of PICC line flipped upward terminating recurrently in the upper superior vena cava .