Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable semi-erect chest film ___ at 15 :43 is submitted .
    OUTPUT:
    
Tracheostomy tube and right subclavian PICC line are unchanged in position . Overall cardiac and mediastinal contours are stable . The patient 's face mask obscures the apices . There is a faint patchy opacity at the left base which could reflect atelectasis , although an early pneumonia could also have this appearance . Clinical correlation is advised and followup imaging should be considered . No evidence of pulmonary edema or pneumothorax .