Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable semi-erect chest radiograph ___ at 22 :27 is submitted .
    OUTPUT:
    
Cardiac and mediastinal contours are stable . There may be a small hiatal hernia . Patchy opacity at the left base may reflect an area of atelectasis , although aspiration or early pneumonia should also be considered . Possible tiny left effusion . No pulmonary edema . No pneumothorax .