Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: In comparison with ___ study there is significant increase in volume loss of the left lung and mild leftward mediastinal shift suggestive of airway obstruction ( mucous plugging ) . Mild pulmonary vascular congestion is also seen . ETT appears to terminate approximately 3 .8 cm superior to the carina . A left PICC line is unchanged in position and terminates at the mid SVC . No pneumothorax is seen .
    OUTPUT:
    
1 . Significant increase in volume loss of the left lung and leftward mediastinal shift suggestive of airway obstruction likely secondary to mucous plugging in an intubated patient . 2 . Mild pulmonary vascular congestion .